Merge remote-tracking branch 'origin/main' into claude/voice-picker-carousel-426nfu

2026-10-05 16:38:09 +00:00 · 2026-10-05 16:38:09 +00:00 · e0c7cf9f84
commit e0c7cf9f84
parent bc7353f1f2 3291a32d37
44 changed files with 2418 additions and 207 deletions
--- a/apps/web/e2e/helpers.ts
+++ b/apps/web/e2e/helpers.ts
@ -245,7 +245,6 @@ export async function openUserSettings(
    | "integrations"
    | "models"
    | "memory"
-    | "profile"
    | "voice"
    | "notifications"
    | "usage"
--- a/apps/web/e2e/media-card.spec.ts
+++ b/apps/web/e2e/media-card.spec.ts
@ -1,3 +1,6 @@
+import { readFileSync } from "node:fs";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
 import type { Page } from "@playwright/test";
 import { expect, test } from "@playwright/test";
 import {
@ -92,6 +95,38 @@ async function seedMediaMessage(page: Page, botId: string, block: () => MediaBlo
  }
 }

+/** CI has no ffmpeg or transcription server; the card asks what the space can run. */
+async function offerFollowUps(page: Page) {
+  await page.route("**/rpc/media/capabilities", (route) =>
+    route.fulfill({
+      contentType: "application/json",
+      body: JSON.stringify({
+        json: {
+          generate_image: false,
+          generate_video: false,
+          edit_image: false,
+          edit_video: false,
+          export_video: true,
+          transcribe: true,
+        },
+      }),
+    }),
+  );
+}
+
+/** Records follow-up jobs the card starts instead of running them. */
+async function recordStartedJobs(page: Page): Promise<unknown[]> {
+  const started: unknown[] = [];
+  await page.route("**/rpc/media/jobs/start", async (route) => {
+    started.push((route.request().postDataJSON() as { json: unknown }).json);
+    await route.fulfill({
+      contentType: "application/json",
+      body: JSON.stringify({ json: { jobId: "media-job-2", messageId: "media-message-next" } }),
+    });
+  });
+  return started;
+}
+
 test("renders a media job card while it runs and when it is done", async ({ page }, testInfo) => {
  const stamp = Date.now();
  await signup(page, `media-card-${stamp}@rakazo.test`, "password12", "Media Card");
@ -150,30 +185,8 @@ test("renders a media job card while it runs and when it is done", async ({ page
          ],
        },
  );
-  // CI has no transcription server; the card asks what the space can run.
-  await page.route("**/rpc/media/capabilities", (route) =>
-    route.fulfill({
-      contentType: "application/json",
-      body: JSON.stringify({
-        json: {
-          generate_image: false,
-          generate_video: false,
-          edit_image: false,
-          edit_video: false,
-          export_video: true,
-          transcribe: true,
-        },
-      }),
-    }),
-  );
-  const started: unknown[] = [];
-  await page.route("**/rpc/media/jobs/start", async (route) => {
-    started.push((route.request().postDataJSON() as { json: unknown }).json);
-    await route.fulfill({
-      contentType: "application/json",
-      body: JSON.stringify({ json: { jobId: "media-job-2", messageId: "media-message-next" } }),
-    });
-  });
+  await offerFollowUps(page);
+  const started = await recordStartedJobs(page);
  await page.reload();

  const card = page.getByTestId("media-card");
@ -209,3 +222,83 @@ test("renders a media job card while it runs and when it is done", async ({ page
    input: { artifact_id: voice.id, title: "voice-note.wav" },
  });
 });
+
+test("a platform export names its platform, shows a failed check and exports for others", async ({
+  page,
+}, testInfo) => {
+  const stamp = Date.now();
+  await signup(page, `media-platform-${stamp}@rakazo.test`, "password12", "Media Platform");
+  await completeOnboarding(page);
+  const botId = activeBotId(page);
+
+  const fixture = path.join(
+    path.dirname(fileURLToPath(import.meta.url)),
+    "fixtures",
+    "media-clip.mp4",
+  );
+  const clip = await rpc<{ id: string; size: number }>(page, "artifacts/create", {
+    botId,
+    name: "clip-tiktok.mp4",
+    mimeType: "video/mp4",
+    contentBase64: readFileSync(fixture).toString("base64"),
+  });
+  await seedMediaMessage(page, botId, () => ({
+    kind: "media",
+    jobId: "media-job-platforms",
+    operation: "export_video",
+    status: "done",
+    title: "TikTok · Snapchat Spotlight",
+    outputs: [
+      {
+        artifactId: clip.id,
+        kind: "video",
+        mimeType: "video/mp4",
+        name: "clip-tiktok.mp4",
+        size: clip.size,
+        width: 1080,
+        height: 1920,
+        durationMs: 1000,
+        platform: "tiktok",
+        check: {
+          status: "fail",
+          issues: [{ code: "file_too_large", maxMb: 287, actualMb: 301.2 }],
+        },
+      },
+    ],
+    skipped: [
+      {
+        platform: "snapchat-spotlight",
+        issues: [{ code: "too_short", minMs: 5000, actualMs: 1000 }],
+      },
+    ],
+  }));
+  await offerFollowUps(page);
+  const started = await recordStartedJobs(page);
+  await page.reload();
+
+  const card = page.getByTestId("media-card");
+  await expect(card).toHaveAttribute("data-status", "done", { timeout: 30_000 });
+  await expect(card).toContainText("Too large for TikTok (max 287 MB)");
+  await expect(card).toContainText("Too short for Snapchat Spotlight (min 0:05)");
+  await captureScreenshot(page, testInfo, "media-card-platform-check");
+
+  await card.getByRole("button", { name: "Export" }).click();
+  const menu = page.getByRole("menu");
+  await expect(menu.getByRole("menuitem", { name: "YouTube Shorts" })).toBeVisible();
+  await expect(menu.getByRole("menuitem", { name: "Instagram Reels" })).toBeVisible();
+  // Not the platform or the shape it already has.
+  await expect(menu.getByRole("menuitem", { name: "TikTok" })).toHaveCount(0);
+  await expect(menu.getByRole("menuitem", { name: "9:16" })).toHaveCount(0);
+  await expect(menu.getByRole("separator")).toHaveCount(1);
+  await expect(menu.getByRole("menuitem", { name: "1:1" })).toBeVisible();
+  await captureScreenshot(page, testInfo, "media-card-platform-export-menu");
+
+  await menu.getByRole("menuitem", { name: "YouTube Shorts" }).click();
+  await expect.poll(() => started.length).toBe(1);
+  expect(started[0]).toEqual({
+    botId,
+    messageId: expect.stringMatching(/^media-message-\d+$/),
+    operation: "export_video",
+    input: { artifact_id: clip.id, platforms: ["youtube-shorts"] },
+  });
+});
--- a/apps/web/e2e/user-profile-edit.spec.ts
+++ b/apps/web/e2e/user-profile-edit.spec.ts
@ -1,5 +1,5 @@
 /**
- * E2E: Settings → About you edits a fact in place: its wording, category and the spaces it
+ * E2E: Settings → General → About you edits a fact in place: its wording, category and the spaces it
 * shows in.
 */
 import { expect, test } from "@playwright/test";
@ -15,7 +15,7 @@ test("a fact's wording, category and spaces are edited in place", async ({ page
    addFacts: [{ category: "preferences", value: "Prefers tea" }],
  });

-  const settings = await openUserSettings(page, "profile");
+  const settings = await openUserSettings(page);
  const profile = settings.getByTestId("user-profile-settings");
  const tea = profile.getByTestId("user-fact").filter({ hasText: "Prefers tea" });
  await tea.getByRole("button", { name: "Edit" }).click();
--- a/apps/web/e2e/user-profile.spec.ts
+++ b/apps/web/e2e/user-profile.spec.ts
@ -1,6 +1,6 @@
 /**
 * E2E: onboarding fills the user profile without asking (time zone, locale and language from
- * the browser) and records the focus answer as a fact; Settings → About you shows every fact
+ * the browser) and records the focus answer as a fact; Settings → General → About you shows every fact
 * with its origin, confirms a pending one, and forgets one or all of them.
 */
 import { expect, test } from "@playwright/test";
@ -58,8 +58,8 @@ test("onboarding feeds the profile; facts can be confirmed and forgotten", async
    addFacts: [{ category: "health", value: "Allergic to peanuts", source: "onboarding" }],
  });

-  const settings = await openUserSettings(page, "profile");
-  await expect(settings).toHaveAttribute("data-settings-section", "profile");
+  const settings = await openUserSettings(page);
+  await expect(settings).toHaveAttribute("data-settings-section", "general");
  const profile = settings.getByTestId("user-profile-settings");
  await expect(profile.getByTestId("profile-field-timeZone")).toContainText("Europe/Vienna");
  await expect(profile.getByTestId("profile-field-language")).toContainText("English");
@ -99,6 +99,6 @@ test("onboarding feeds the profile; facts can be confirmed and forgotten", async

  await profile.getByRole("button", { name: "Forget everything" }).click();
  await page.getByRole("alertdialog").getByRole("button", { name: "Forget", exact: true }).click();
-  await expect(profile).toContainText("Nothing yet");
+  await expect(profile).toHaveCount(0);
  expect(await rpc<{ facts: unknown[] }>(page, "profile/get", null)).toMatchObject({ facts: [] });
 });
--- a/apps/web/src/components/UserProfileSettings.tsx
+++ b/apps/web/src/components/UserProfileSettings.tsx
@ -151,20 +151,22 @@ export function UserProfileSettings() {
    </Button>
  );

+  if (!error && (!state || (fields.length === 0 && groups.length === 0))) return null;
+
  return (
-    <div data-testid="user-profile-settings" className="space-y-5">
+    <section
+      data-testid="user-profile-settings"
+      className="space-y-4 rounded-xl border border-border px-4 py-4"
+    >
+      <h3 className="text-ui-body font-medium text-foreground">
+        <Trans>About you</Trans>
+      </h3>
      {error ? (
        <p role="alert" className="text-ui-body-sm text-destructive">
          {error}
        </p>
      ) : null}
-      {state && fields.length === 0 && groups.length === 0 ? (
-        <p className="text-ui-body-sm text-muted-foreground">
-          <Trans>Nothing yet</Trans>
-        </p>
-      ) : null}
      {fields.length > 0 ? (
-        <section className="rounded-xl border border-border px-4 py-4">
        <ul className="space-y-3">
          {fields.map(({ field, value }) => (
            <Row
@ -187,18 +189,13 @@ export function UserProfileSettings() {
            />
          ))}
        </ul>
-        </section>
      ) : null}
      {groups.map((group) => (
-        <section
-          key={group.category}
-          data-testid={`user-facts-${group.category}`}
-          className="rounded-xl border border-border px-4 py-4"
-        >
-          <h3 className="text-ui-body font-medium text-foreground">
+        <div key={group.category} data-testid={`user-facts-${group.category}`}>
+          <h4 className="text-ui-body-sm text-muted-foreground">
            {categoryLabels[group.category]}
-          </h3>
-          <ul className="mt-3 space-y-3">
+          </h4>
+          <ul className="mt-2 space-y-3">
            {group.facts.map((fact) =>
              fact.id === editingId ? (
                <UserFactEditor
@ -269,7 +266,7 @@ export function UserProfileSettings() {
              ),
            )}
          </ul>
-        </section>
+        </div>
      ))}
      {fields.length > 0 || groups.length > 0 ? (
        <Button variant="destructive" disabled={busy} onClick={() => setForgetOpen(true)}>
@ -300,6 +297,6 @@ export function UserProfileSettings() {
          </AlertDialogFooter>
        </AlertDialogContent>
      </AlertDialog>
-    </div>
+    </section>
  );
 }
--- a/apps/web/src/components/media/MediaCard.test.tsx
+++ b/apps/web/src/components/media/MediaCard.test.tsx
@ -8,6 +8,10 @@ vi.mock("@lingui/react/macro", () => {
    parts.reduce((text, part, index) => `${text}${part}${values[index] ?? ""}`, "");
  return { useLingui: () => ({ t }), Trans: ({ children }: { children: ReactNode }) => children };
 });
+vi.mock("@lingui/core/macro", () => ({
+  t: (parts: TemplateStringsArray, ...values: unknown[]) =>
+    parts.reduce((out, part, index) => `${out}${String(values[index - 1])}${part}`),
+}));
 vi.mock("../../pages/shell/message-cards", () => ({
  ArtifactImage: ({ artifactId, name }: { artifactId: string; name: string }) => (
    <img data-artifact={artifactId} alt={name} />
@ -147,6 +151,65 @@ describe("media card", () => {
    expect(html).not.toContain("Transcribe");
  });

+  it("names the platform of an export, and its first problem only when the check did not pass", () => {
+    const tiktok = {
+      ...video,
+      artifactId: "tiktok-1",
+      platform: "tiktok" as const,
+      check: { status: "pass" as const, issues: [] },
+    };
+    const shorts = {
+      ...video,
+      artifactId: "shorts-1",
+      platform: "youtube-shorts" as const,
+      check: {
+        status: "warn" as const,
+        issues: [
+          { code: "loudness_off" as const, targetLufs: -14, actualLufs: -18 },
+          { code: "true_peak_high" as const, maxDb: -1, actualDb: 0 },
+        ],
+      },
+    };
+    const html = renderToString(
+      <MediaCardView
+        block={block({ operation: "export_video", outputs: [tiktok, shorts, video] })}
+      />,
+    );
+    expect(html).toContain('<p class="text-ui-body-sm text-muted-foreground">TikTok</p>');
+    expect(html).toContain(
+      '<p class="text-ui-body-sm text-warning">Too quiet for YouTube Shorts (target -14 LUFS)</p>',
+    );
+    expect(html).not.toContain("Peaks too high");
+    expect(html.match(/text-ui-body-sm text-(muted-foreground|warning|destructive)/g)).toHaveLength(
+      2,
+    );
+  });
+
+  it("lists skipped platforms, which also explain a job that rendered nothing", () => {
+    const skipped = [
+      {
+        platform: "snapchat-spotlight" as const,
+        issues: [{ code: "too_long" as const, maxMs: 60_000, actualMs: 75_000 }],
+      },
+    ];
+    const partial = renderToString(
+      <MediaCardView block={block({ operation: "export_video", outputs: [video], skipped })} />,
+    );
+    expect(partial).toContain("Too long for Snapchat Spotlight (max 1:00)");
+    const failed = renderToString(
+      <MediaCardView
+        block={block({
+          operation: "export_video",
+          status: "failed",
+          error: "Not exported for Snapchat Spotlight: 75 s is longer than its 60 s limit",
+          skipped,
+        })}
+      />,
+    );
+    expect(failed).toContain("Too long for Snapchat Spotlight (max 1:00)");
+    expect(failed).not.toContain("Not exported");
+  });
+
  it("shows why a job failed", () => {
    const html = renderToString(
      <MediaCardView block={block({ status: "failed", error: "GPU server is unreachable" })} />,
--- a/apps/web/src/components/media/MediaCard.tsx
+++ b/apps/web/src/components/media/MediaCard.tsx
@ -4,6 +4,7 @@ import type {
  MediaJobStatus,
  MediaOperation,
  MediaOutput,
+  MediaPlatformId,
  MediaPresetId,
 } from "@rakazo/contracts";
 import { MEDIA_JOB_ACTIVE_STATUSES, MEDIA_PRESETS, MediaPresetIdSchema } from "@rakazo/contracts";
@ -14,6 +15,7 @@ import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
+  DropdownMenuSeparator,
  DropdownMenuTrigger,
 } from "@rakazo/ui-web";
 import type { LucideIcon } from "lucide-react";
@ -26,12 +28,14 @@ import { ArtifactImage } from "../../pages/shell/message-cards";
 import { ArtifactFileCard } from "../ArtifactFileCard";
 import { Shimmer } from "../ai/primitives";
 import { MediaPlayer } from "./MediaPlayer";
+import { exportPlatformsFor, platformIssueLine, platformName } from "./media-platforms";

 const CARD_CLASS =
  "w-[min(480px,96%)] rounded-[18px] border border-border bg-card/75 p-3.5 text-start shadow-xs";

 export type MediaCardAction =
  | { kind: "export"; artifactId: string; preset: MediaPresetId }
+  | { kind: "export"; artifactId: string; platform: MediaPlatformId }
  | { kind: "transcribe"; artifactId: string; name: string }
  | { kind: "cancel" };

@ -114,6 +118,7 @@ function OutputActions({
 }) {
  const { t } = useLingui();
  const name = output.name;
+  const platforms = output.kind === "video" ? exportPlatformsFor(output) : [];
  const presets = output.kind === "video" ? exportPresetsFor(output) : [];
  return (
    <div className="flex flex-wrap items-center gap-1.5">
@ -129,7 +134,7 @@ function OutputActions({
      >
        <Download />
      </a>
-      {onAction && available.export && presets.length > 0 ? (
+      {onAction && available.export && platforms.length + presets.length > 0 ? (
        <DropdownMenu>
          <DropdownMenuTrigger
            disabled={busy}
@ -140,6 +145,17 @@ function OutputActions({
            <ChevronDown />
          </DropdownMenuTrigger>
          <DropdownMenuContent className="w-auto min-w-24">
+            {platforms.map((platform) => (
+              <DropdownMenuItem
+                key={platform}
+                onClick={() =>
+                  onAction({ kind: "export", artifactId: output.artifactId, platform })
+                }
+              >
+                {platformName(platform)}
+              </DropdownMenuItem>
+            ))}
+            {platforms.length > 0 && presets.length > 0 ? <DropdownMenuSeparator /> : null}
            {presets.map((preset) => (
              <DropdownMenuItem
                key={preset}
@ -168,6 +184,26 @@ function OutputActions({
  );
 }

+/** The platform an output was exported for, or its first problem there. */
+function PlatformLine({ output }: { output: MediaOutput }) {
+  if (!output.platform) return null;
+  const issue = output.check?.status === "pass" ? undefined : output.check?.issues[0];
+  return (
+    <p
+      className={cn(
+        "text-ui-body-sm",
+        !issue
+          ? "text-muted-foreground"
+          : output.check?.status === "fail"
+            ? "text-destructive"
+            : "text-warning",
+      )}
+    >
+      {issue ? platformIssueLine(output.platform, issue) : platformName(output.platform)}
+    </p>
+  );
+}
+
 /**
 * The live card of a media job: what it makes, how far it is, and the results with the
 * follow-ups that fit them (export other formats, transcribe). Nothing else is shown.
@ -191,6 +227,10 @@ export function MediaCardView({
  const percent = Math.round((block.progress ?? 0) * 100);
  const images = block.outputs.filter((output) => output.kind === "image");
  const others = block.outputs.filter((output) => output.kind !== "image");
+  const skipped = block.skipped ?? [];
+  // When nothing was rendered because every platform was skipped, the skipped lines say why.
+  const showError =
+    block.status === "failed" && block.error && !(skipped.length && !block.outputs.length);

  const act = onAction
    ? (action: MediaCardAction) => {
@ -251,7 +291,7 @@ export function MediaCardView({
            />
          </div>
        ) : null}
-        {block.status === "failed" && block.error ? (
+        {showError ? (
          <p className="mt-2 text-ui-body-sm text-destructive" dir="auto">
            {block.error}
          </p>
@ -279,6 +319,7 @@ export function MediaCardView({
                  width={output.width}
                  height={output.height}
                />
+                <PlatformLine output={output} />
                {active ? null : (
                  <OutputActions output={output} available={available} busy={busy} onAction={act} />
                )}
@ -293,6 +334,11 @@ export function MediaCardView({
            )}
          </div>
        ))}
+        {skipped.map((target) => (
+          <p key={target.platform} className="mt-2 text-ui-body-sm text-destructive">
+            {platformIssueLine(target.platform, target.issues[0]!)}
+          </p>
+        ))}
        {actionError ? (
          <p role="alert" className="mt-2 text-ui-body-sm text-destructive" dir="auto">
            {actionError}
@ -383,7 +429,10 @@ export function MediaCard({
      ...(action.kind === "export"
        ? {
            operation: "export_video",
-            input: { artifact_id: action.artifactId, presets: [action.preset] },
+            input:
+              "platform" in action
+                ? { artifact_id: action.artifactId, platforms: [action.platform] }
+                : { artifact_id: action.artifactId, presets: [action.preset] },
          }
        : // The new card is titled with the file it transcribes.
          {
--- a/apps/web/src/components/media/media-platforms.test.ts
+++ b/apps/web/src/components/media/media-platforms.test.ts
@ -0,0 +1,75 @@
+import type { MediaCheckIssue } from "@rakazo/contracts";
+import { describe, expect, it, vi } from "vitest";
+
+// The macros compile at build time; here the English source comes back with its values filled in.
+vi.mock("@lingui/core/macro", () => ({
+  t: (parts: TemplateStringsArray, ...values: unknown[]) =>
+    parts.reduce((out, part, index) => `${out}${String(values[index - 1])}${part}`),
+}));
+
+import {
+  clockDuration,
+  exportPlatformsFor,
+  platformIssueLine,
+  platformName,
+} from "./media-platforms";
+
+describe("export platforms", () => {
+  it("offers every platform but the one the video was exported for, by brand name", () => {
+    expect(exportPlatformsFor({})).toHaveLength(10);
+    expect(exportPlatformsFor({ platform: "tiktok" })).not.toContain("tiktok");
+    expect(exportPlatformsFor({}).slice(0, 4).map(platformName)).toEqual([
+      "TikTok",
+      "Instagram Reels",
+      "Instagram Feed",
+      "YouTube Shorts",
+    ]);
+  });
+});
+
+describe("platform issue lines", () => {
+  it("formats limits as a clock", () => {
+    expect(clockDuration(600_000)).toBe("10:00");
+    expect(clockDuration(5000)).toBe("0:05");
+    expect(clockDuration(3_723_000)).toBe("1:02:03");
+  });
+
+  it.each<[MediaCheckIssue, string]>([
+    [{ code: "too_long", maxMs: 600_000, actualMs: 720_000 }, "Too long for TikTok (max 10:00)"],
+    [{ code: "too_short", minMs: 3000, actualMs: 1000 }, "Too short for TikTok (min 0:03)"],
+    [{ code: "file_too_large", maxMb: 287, actualMb: 301.2 }, "Too large for TikTok (max 287 MB)"],
+    [
+      { code: "bitrate_high", maxKbps: 8000, actualKbps: 9500 },
+      "Bitrate too high for TikTok (max 8,000 kbps)",
+    ],
+    [
+      { code: "loudness_off", targetLufs: -14, actualLufs: -18.2 },
+      "Too quiet for TikTok (target -14 LUFS)",
+    ],
+    [
+      { code: "loudness_off", targetLufs: -14, actualLufs: -9.5 },
+      "Too loud for TikTok (target -14 LUFS)",
+    ],
+    [
+      { code: "true_peak_high", maxDb: -1, actualDb: 0.2 },
+      "Peaks too high for TikTok (max -1 dBTP)",
+    ],
+    [
+      {
+        code: "resolution_mismatch",
+        width: 1080,
+        height: 1920,
+        actualWidth: 720,
+        actualHeight: 1280,
+      },
+      "Wrong size for TikTok (needs 1080×1920)",
+    ],
+    [
+      { code: "fps_mismatch", maxFps: 30, actualFps: 60 },
+      "Frame rate too high for TikTok (max 30 fps)",
+    ],
+    [{ code: "codec_mismatch" }, "Wrong format for TikTok (needs H.264)"],
+  ])("words %j in one short line", (issue, line) => {
+    expect(platformIssueLine("tiktok", issue)).toBe(line);
+  });
+});
--- a/apps/web/src/components/media/media-platforms.ts
+++ b/apps/web/src/components/media/media-platforms.ts
@ -0,0 +1,72 @@
+import { i18n } from "@lingui/core";
+import { t } from "@lingui/core/macro";
+import type { MediaCheckIssue, MediaOutput, MediaPlatformId } from "@rakazo/contracts";
+import { MEDIA_PLATFORM_PROFILES, MediaPlatformIdSchema } from "@rakazo/contracts";
+
+/** Platforms a video can be exported for: all but the one it was exported for. */
+export function exportPlatformsFor(output: Pick<MediaOutput, "platform">): MediaPlatformId[] {
+  return MediaPlatformIdSchema.options.filter((id) => id !== output.platform);
+}
+
+/** The platform's brand name, never translated. */
+export function platformName(platform: MediaPlatformId): string {
+  return MEDIA_PLATFORM_PROFILES[platform].name;
+}
+
+/** "10:00", or "1:02:03" past an hour. */
+export function clockDuration(ms: number): string {
+  const total = Math.round(ms / 1000);
+  const hours = Math.floor(total / 3600);
+  const minutes = Math.floor((total % 3600) / 60);
+  const seconds = String(total % 60).padStart(2, "0");
+  return hours > 0
+    ? `${hours}:${String(minutes).padStart(2, "0")}:${seconds}`
+    : `${minutes}:${seconds}`;
+}
+
+function amount(value: number): string {
+  return new Intl.NumberFormat(i18n.locale || "en", { maximumFractionDigits: 1 }).format(value);
+}
+
+/** One short line for a check issue, e.g. "Too long for TikTok (max 10:00)". */
+export function platformIssueLine(platform: MediaPlatformId, issue: MediaCheckIssue): string {
+  const name = platformName(platform);
+  switch (issue.code) {
+    case "too_long": {
+      const max = clockDuration(issue.maxMs);
+      return t`Too long for ${name} (max ${max})`;
+    }
+    case "too_short": {
+      const min = clockDuration(issue.minMs);
+      return t`Too short for ${name} (min ${min})`;
+    }
+    case "file_too_large": {
+      const max = amount(issue.maxMb);
+      return t`Too large for ${name} (max ${max} MB)`;
+    }
+    case "bitrate_high": {
+      const max = amount(issue.maxKbps);
+      return t`Bitrate too high for ${name} (max ${max} kbps)`;
+    }
+    case "loudness_off": {
+      const target = amount(issue.targetLufs);
+      return issue.actualLufs < issue.targetLufs
+        ? t`Too quiet for ${name} (target ${target} LUFS)`
+        : t`Too loud for ${name} (target ${target} LUFS)`;
+    }
+    case "true_peak_high": {
+      const max = amount(issue.maxDb);
+      return t`Peaks too high for ${name} (max ${max} dBTP)`;
+    }
+    case "resolution_mismatch": {
+      const size = `${issue.width}×${issue.height}`;
+      return t`Wrong size for ${name} (needs ${size})`;
+    }
+    case "fps_mismatch": {
+      const max = amount(issue.maxFps);
+      return t`Frame rate too high for ${name} (max ${max} fps)`;
+    }
+    case "codec_mismatch":
+      return t`Wrong format for ${name} (needs H.264)`;
+  }
+}
--- a/apps/web/src/locales/de/messages.po
+++ b/apps/web/src/locales/de/messages.po
@ -311,7 +311,7 @@ msgstr "Über Gruppen"
 msgid "About spaces"
 msgstr "Über Spaces"

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr "Über dich"

@ -835,6 +835,10 @@ msgstr "Bearer-Token"
 msgid "Bell"
 msgstr "Glöckchen"

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr "Bitrate zu hoch für {name} (maximal {max} kbps)"
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr "In deinen Browser-Einstellungen blockiert"
@ -2529,6 +2533,10 @@ msgstr "Passwort vergessen?"
 msgid "Forward"
 msgstr "Vorwärts"

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr "Bildrate zu hoch für {name} (maximal {max} fps)"
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr "Sommersprossen"
@ -3607,10 +3615,6 @@ msgstr "Nichts läuft mehr"
 msgid "Nothing remembered yet"
 msgstr "Noch nichts gemerkt"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr "Noch nichts"
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr "Pfote"
 msgid "Peach"
 msgstr "Pfirsich"

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr "Pegelspitzen zu hoch für {name} (maximal {max} dBTP)"
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr "Pinguin"
@ -5075,6 +5083,26 @@ msgstr "Heute"
 msgid "Today, {heuteActionCount} need you"
 msgstr "Heute, {heuteActionCount} brauchen dich"

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr "Zu groß für {name} (maximal {max} MB)"
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr "Zu lang für {name} (maximal {max})"
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr "Zu laut für {name} (Zielwert {target} LUFS)"
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr "Zu leise für {name} (Zielwert {target} LUFS)"
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr "Zu kurz für {name} (mindestens {min})"
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "Toolquellen"
@ -5494,6 +5522,14 @@ msgstr "Arbeitet…"
 msgid "Working…"
 msgstr "Wird verarbeitet…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr "Falsches Format für {name} (braucht H.264)"
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr "Falsche Größe für {name} (braucht {size})"
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "Gestern"
--- a/apps/web/src/locales/en/messages.po
+++ b/apps/web/src/locales/en/messages.po
@ -311,7 +311,7 @@ msgstr "About groups"
 msgid "About spaces"
 msgstr "About spaces"

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr "About you"

@ -835,6 +835,10 @@ msgstr "Bearer token"
 msgid "Bell"
 msgstr "Bell"

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr "Bitrate too high for {name} (max {max} kbps)"
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr "Blocked in your browser settings"
@ -2529,6 +2533,10 @@ msgstr "Forgot password?"
 msgid "Forward"
 msgstr "Forward"

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr "Frame rate too high for {name} (max {max} fps)"
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr "Freckles"
@ -3607,10 +3615,6 @@ msgstr "Nothing is still running"
 msgid "Nothing remembered yet"
 msgstr "Nothing remembered yet"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr "Nothing yet"
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr "Paw"
 msgid "Peach"
 msgstr "Peach"

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr "Peaks too high for {name} (max {max} dBTP)"
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr "Penguin"
@ -5075,6 +5083,26 @@ msgstr "Today"
 msgid "Today, {heuteActionCount} need you"
 msgstr "Today, {heuteActionCount} need you"

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr "Too large for {name} (max {max} MB)"
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr "Too long for {name} (max {max})"
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr "Too loud for {name} (target {target} LUFS)"
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr "Too quiet for {name} (target {target} LUFS)"
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr "Too short for {name} (min {min})"
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "Tool sources"
@ -5494,6 +5522,14 @@ msgstr "Working…"
 msgid "Working…"
 msgstr "Working…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr "Wrong format for {name} (needs H.264)"
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr "Wrong size for {name} (needs {size})"
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "Yesterday"
--- a/apps/web/src/locales/es/messages.po
+++ b/apps/web/src/locales/es/messages.po
@ -311,7 +311,7 @@ msgstr ""
 msgid "About spaces"
 msgstr ""

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr ""

@ -835,6 +835,10 @@ msgstr "Token Bearer"
 msgid "Bell"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr ""
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr ""
@ -2529,6 +2533,10 @@ msgstr "¿Olvidaste la contraseña?"
 msgid "Forward"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr ""
@ -3607,10 +3615,6 @@ msgstr "No queda nada en ejecución"
 msgid "Nothing remembered yet"
 msgstr "Aún no hay recuerdos"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr ""
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr ""
 msgid "Peach"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr ""
@ -5075,6 +5083,26 @@ msgstr ""
 msgid "Today, {heuteActionCount} need you"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr ""
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "Fuentes de herramientas"
@ -5494,6 +5522,14 @@ msgstr "Trabajando…"
 msgid "Working…"
 msgstr "Trabajando…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr ""
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "Ayer"
--- a/apps/web/src/locales/hi/messages.po
+++ b/apps/web/src/locales/hi/messages.po
@ -311,7 +311,7 @@ msgstr ""
 msgid "About spaces"
 msgstr ""

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr ""

@ -835,6 +835,10 @@ msgstr "बियरर टोकन"
 msgid "Bell"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr ""
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr ""
@ -2529,6 +2533,10 @@ msgstr "पासवर्ड भूल गए?"
 msgid "Forward"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr ""
@ -3607,10 +3615,6 @@ msgstr "कुछ भी नहीं चल रहा"
 msgid "Nothing remembered yet"
 msgstr "अभी तक कुछ याद नहीं किया गया"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr ""
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr ""
 msgid "Peach"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr ""
@ -5075,6 +5083,26 @@ msgstr ""
 msgid "Today, {heuteActionCount} need you"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr ""
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "टूल स्रोत"
@ -5494,6 +5522,14 @@ msgstr "काम चल रहा है…"
 msgid "Working…"
 msgstr "काम चल रहा है…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr ""
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "कल"
--- a/apps/web/src/locales/ko/messages.po
+++ b/apps/web/src/locales/ko/messages.po
@ -311,7 +311,7 @@ msgstr ""
 msgid "About spaces"
 msgstr ""

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr ""

@ -835,6 +835,10 @@ msgstr "Bearer 토큰"
 msgid "Bell"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr ""
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr ""
@ -2529,6 +2533,10 @@ msgstr "비밀번호를 잊으셨나요?"
 msgid "Forward"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr ""
@ -3607,10 +3615,6 @@ msgstr "실행 중인 작업 없음"
 msgid "Nothing remembered yet"
 msgstr "아직 기억한 내용이 없습니다"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr ""
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr ""
 msgid "Peach"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr ""
@ -5075,6 +5083,26 @@ msgstr ""
 msgid "Today, {heuteActionCount} need you"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr ""
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "도구 소스"
@ -5494,6 +5522,14 @@ msgstr "처리 중…"
 msgid "Working…"
 msgstr "처리 중…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr ""
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "어제"
--- a/apps/web/src/locales/pt-BR/messages.po
+++ b/apps/web/src/locales/pt-BR/messages.po
@ -311,7 +311,7 @@ msgstr ""
 msgid "About spaces"
 msgstr ""

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr ""

@ -835,6 +835,10 @@ msgstr "Token portador"
 msgid "Bell"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr ""
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr ""
@ -2529,6 +2533,10 @@ msgstr "Esqueceu a senha?"
 msgid "Forward"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr ""
@ -3607,10 +3615,6 @@ msgstr "Nada ainda está em execução"
 msgid "Nothing remembered yet"
 msgstr "Nada memorizado ainda"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr ""
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr ""
 msgid "Peach"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr ""
@ -5075,6 +5083,26 @@ msgstr ""
 msgid "Today, {heuteActionCount} need you"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr ""
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "Fontes de ferramentas"
@ -5494,6 +5522,14 @@ msgstr "Funcionando"
 msgid "Working…"
 msgstr "Funcionando"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr ""
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "Ontem"
--- a/apps/web/src/locales/ru/messages.po
+++ b/apps/web/src/locales/ru/messages.po
@ -311,7 +311,7 @@ msgstr "О группах"
 msgid "About spaces"
 msgstr "О пространствах"

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr ""

@ -835,6 +835,10 @@ msgstr "Bearer-токен"
 msgid "Bell"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr ""
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr ""
@ -2529,6 +2533,10 @@ msgstr "Забыли пароль?"
 msgid "Forward"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr ""
@ -3607,10 +3615,6 @@ msgstr ""
 msgid "Nothing remembered yet"
 msgstr "Пока ничего не запомнено"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr ""
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr ""
 msgid "Peach"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr ""
@ -5075,6 +5083,26 @@ msgstr ""
 msgid "Today, {heuteActionCount} need you"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr ""
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "Источники инструментов"
@ -5494,6 +5522,14 @@ msgstr "Выполняется…"
 msgid "Working…"
 msgstr "Выполняется…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr ""
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "Вчера"
--- a/apps/web/src/locales/tr/messages.po
+++ b/apps/web/src/locales/tr/messages.po
@ -311,7 +311,7 @@ msgstr ""
 msgid "About spaces"
 msgstr ""

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr ""

@ -835,6 +835,10 @@ msgstr "Bearer token"
 msgid "Bell"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr ""
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr ""
@ -2529,6 +2533,10 @@ msgstr "Parolanızı mı unuttunuz?"
 msgid "Forward"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr ""
@ -3607,10 +3615,6 @@ msgstr "Hâlâ çalışan bir şey yok"
 msgid "Nothing remembered yet"
 msgstr "Henüz hatırlanan bir şey yok"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr ""
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr ""
 msgid "Peach"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr ""
@ -5075,6 +5083,26 @@ msgstr ""
 msgid "Today, {heuteActionCount} need you"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr ""
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "Araç kaynakları"
@ -5494,6 +5522,14 @@ msgstr "Çalışıyor…"
 msgid "Working…"
 msgstr "Çalışıyor…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr ""
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "Dün"
--- a/apps/web/src/locales/zh-CN/messages.po
+++ b/apps/web/src/locales/zh-CN/messages.po
@ -311,7 +311,7 @@ msgstr ""
 msgid "About spaces"
 msgstr ""

-#: src/pages/SettingsOverlay.tsx
+#: src/components/UserProfileSettings.tsx
 msgid "About you"
 msgstr ""

@ -835,6 +835,10 @@ msgstr "Bearer token"
 msgid "Bell"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Bitrate too high for {name} (max {max} kbps)"
+msgstr ""
+
 #: src/components/NotificationSettingsPanel.tsx
 msgid "Blocked in your browser settings"
 msgstr ""
@ -2529,6 +2533,10 @@ msgstr "忘记密码？"
 msgid "Forward"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Frame rate too high for {name} (max {max} fps)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Freckles"
 msgstr ""
@ -3607,10 +3615,6 @@ msgstr "没有仍在运行的任务"
 msgid "Nothing remembered yet"
 msgstr "暂无记忆"

-#: src/components/UserProfileSettings.tsx
-msgid "Nothing yet"
-msgstr ""
-
 #: src/pages/SettingsOverlay.tsx
 #: src/pages/shell/bot-panel.tsx
 msgid "Notifications"
@ -3815,6 +3819,10 @@ msgstr ""
 msgid "Peach"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Peaks too high for {name} (max {max} dBTP)"
+msgstr ""
+
 #: src/components/OoAtelier.tsx
 msgid "Penguin"
 msgstr ""
@ -5075,6 +5083,26 @@ msgstr ""
 msgid "Today, {heuteActionCount} need you"
 msgstr ""

+#: src/components/media/media-platforms.ts
+msgid "Too large for {name} (max {max} MB)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too long for {name} (max {max})"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too loud for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too quiet for {name} (target {target} LUFS)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Too short for {name} (min {min})"
+msgstr ""
+
 #: src/pages/PluginsOverlay.tsx
 msgid "Tool sources"
 msgstr "工具源"
@ -5494,6 +5522,14 @@ msgstr "处理中…"
 msgid "Working…"
 msgstr "处理中…"

+#: src/components/media/media-platforms.ts
+msgid "Wrong format for {name} (needs H.264)"
+msgstr ""
+
+#: src/components/media/media-platforms.ts
+msgid "Wrong size for {name} (needs {size})"
+msgstr ""
+
 #: src/pages/shell/roster-format.ts
 msgid "Yesterday"
 msgstr "昨天"
--- a/apps/web/src/pages/AccountSettingsOverlay.tsx
+++ b/apps/web/src/pages/AccountSettingsOverlay.tsx
@ -15,6 +15,7 @@ import { SuccessPop } from "../components/ai/primitives";
 import { ComputersUnavailableHint } from "../components/ComputersUnavailableHint";
 import { DesktopUpdateSection } from "../components/DesktopUpdates";
 import { SoftwareUpdateSection } from "../components/SoftwareUpdateSection";
+import { UserProfileSettings } from "../components/UserProfileSettings";
 import { authClient } from "../lib/auth";
 import { getActiveUiLocale, setUiLocale } from "../lib/i18n";
 import {
@ -67,6 +68,8 @@ export function GeneralSettingsPanels({
        {email ? <p className="mt-1 text-ui-body-sm text-muted-foreground/70">{email}</p> : null}
      </section>

+      <UserProfileSettings />
+
      <ChangePasswordSection email={email} />

      {messagingEnabled && onOpenMessaging ? (
--- a/apps/web/src/pages/SettingsOverlay.tsx
+++ b/apps/web/src/pages/SettingsOverlay.tsx
@ -12,7 +12,6 @@ import {
  Monitor,
  Settings,
  ShieldCheck,
-  UserRound,
  Volume2,
  XIcon,
 } from "lucide-react";
@ -20,7 +19,6 @@ import { type ComponentType, useEffect, useRef, useState } from "react";
 import { computersAreUnavailable } from "../components/ComputersUnavailableHint";
 import { MediaSettings } from "../components/MediaSettings";
 import { NotificationSettingsPanel } from "../components/NotificationSettingsPanel";
-import { UserProfileSettings } from "../components/UserProfileSettings";
 import {
  ComputerSettingsPanel,
  GeneralSettingsPanels,
@ -38,7 +36,6 @@ export type SettingsSection =
  | "integrations"
  | "models"
  | "memory"
-  | "profile"
  | "voice"
  | "media"
  | "notifications"
@ -108,7 +105,6 @@ export function SettingsOverlay({
    { id: "integrations", label: t`Integrations`, icon: LayoutGrid },
    { id: "models", label: t`Models`, icon: Cpu },
    { id: "memory", label: t`Memory`, icon: Brain },
-    { id: "profile", label: t`About you`, icon: UserRound },
    { id: "voice", label: t`Voice`, icon: Volume2 },
    ...(isDeploymentOwner ? [{ id: "media" as const, label: t`Media`, icon: Clapperboard }] : []),
    { id: "notifications", label: t`Notifications`, icon: Bell },
@ -247,7 +243,6 @@ export function SettingsOverlay({
                  onOpenMcp={onOpenMcp ? () => leaveSettings(onOpenMcp) : undefined}
                />
              ) : null}
-              {section === "profile" ? <UserProfileSettings /> : null}
              {section === "media" && isDeploymentOwner ? <MediaSettings /> : null}
              {section === "notifications" ? <NotificationSettingsPanel /> : null}
              {section === "usage" ? (
--- a/packages/adapter-kit/src/media.ts
+++ b/packages/adapter-kit/src/media.ts
@ -1,9 +1,12 @@
 import type {
+  MediaCheck,
  MediaJobStatus,
  MediaOperation,
  MediaOutput,
  MediaOutputKind,
+  MediaPlatformId,
  MediaPresetId,
+  MediaSkippedTarget,
 } from "@rakazo/contracts";
 import type { AdapterDescriptor } from "./types.js";

@ -137,6 +140,8 @@ export interface MediaJobOutputFile {
  posterPath?: string;
  parentArtifactId?: string;
  preset?: MediaPresetId;
+  platform?: MediaPlatformId;
+  check?: MediaCheck;
 }

 /** An artifact the job may read, copied into the job's temp directory. */
@ -168,6 +173,8 @@ export interface MediaJobContext {
  fetchArtifact(artifactId: string): Promise<MediaJobInputFile>;
  /** Stores a produced file as an artifact and adds it to the media card. */
  addOutput(file: MediaJobOutputFile): Promise<MediaOutput>;
+  /** Shows a platform the job did not render on the media card, with the reason. */
+  addSkipped(target: MediaSkippedTarget): Promise<void>;
 }

 export interface MediaOperationResult {
--- a/packages/adapters/src/builtin-tools.ts
+++ b/packages/adapters/src/builtin-tools.ts
@ -7,6 +7,7 @@ import {
  ExportVideoInputSchema,
  GenerateImageInputSchema,
  GenerateVideoInputSchema,
+  MEDIA_PLATFORM_PROFILES,
  MODEL_TIERS,
  SecretAskPurpose,
  SecretHttpRequest,
@ -34,6 +35,11 @@ export const SUBAGENT_MODEL_TIER_DESCRIPTION =
 const VIDEO_PRESETS_AND_FITS =
  "Presets: vertical 9:16, landscape 16:9, square 1:1, portrait 4:5, classic 4:3, cinema 21:9. fit: crop (default) fills the frame and cuts the edges, pad adds bars, blur fills the bars with a blurred copy.";

+/** "tiktok 600 s, …": each platform id with the longest video it takes. */
+const VIDEO_PLATFORMS = Object.values(MEDIA_PLATFORM_PROFILES)
+  .map((profile) => `${profile.id} ${profile.duration.hardMaxMs / 1000} s`)
+  .join(", ");
+
 export const DELEGATION_TOOL_NAMES = new Set([
  "run_subagent",
  "spawn_bot",
@ -564,7 +570,7 @@ export const builtinAgentTools: ConnectorTool[] = [
  },
  {
    name: "export_video",
-    description: `Export a video artifact as one H.264/AAC MP4 per preset. ${VIDEO_PRESETS_AND_FITS} For cuts, speed, audio or subtitles use edit_video.`,
+    description: `Export a video artifact as one H.264/AAC MP4 per platform and per preset, 6 at most. When the user names where it will be posted, use platforms: each file is fitted to that platform's frame, frame rate, bitrate and loudness, then checked. Platforms (longest video): ${VIDEO_PLATFORMS}. A platform the video is too long or too short for is skipped: trim with edit_video first. ${VIDEO_PRESETS_AND_FITS} For cuts, speed, audio or subtitles use edit_video.`,
    inputSchema: mediaParameters(ExportVideoInputSchema),
  },
  {
--- a/packages/adapters/src/media-runtime.postgres.test.ts
+++ b/packages/adapters/src/media-runtime.postgres.test.ts
@ -335,6 +335,25 @@ describePostgres("media job runtime (PostgreSQL, fake operations)", () => {
    expect(existsSync(tempDir)).toBe(false);
  });

+  it("keeps one skipped entry per platform when a job reports it again", async () => {
+    const tooLong = { code: "too_long", maxMs: 600_000, actualMs: 700_000 } as const;
+    const tooShort = { code: "too_short", minMs: 3_000, actualMs: 1_000 } as const;
+    const ctx = await setup({
+      run: async (context) => {
+        await context.addSkipped({ platform: "tiktok", issues: [tooLong] });
+        await context.addSkipped({ platform: "tiktok", issues: [tooShort] });
+        await context.addSkipped({ platform: "youtube", issues: [tooShort] });
+        return { summary: "Skipped." };
+      },
+    });
+    const { jobId } = await ctx.start({ prompt: "fox" });
+    await ctx.runtime.runJob(jobId);
+    expect((await ctx.card(jobId)).skipped).toEqual([
+      { platform: "tiktok", issues: [tooShort] },
+      { platform: "youtube", issues: [tooShort] },
+    ]);
+  });
+
  it("refuses outputs outside the temp dir and sources of another user", async () => {
    const other = await setup();
    const foreign = await other.sourceArtifact();
--- a/packages/adapters/src/media-runtime.ts
+++ b/packages/adapters/src/media-runtime.ts
@ -32,12 +32,14 @@ import type {
  MediaJobStatus,
  MediaOperation,
  MediaOutput,
+  MediaSkippedTarget,
  MessageBlock,
 } from "@rakazo/contracts";
 import {
  attachmentKindOf,
  MEDIA_JOB_ACTIVE_STATUSES,
  MediaOperationSchema,
+  MediaSkippedTargetSchema,
 } from "@rakazo/contracts";
 import { attachmentExtensionForMimeType, inferAttachmentMimeType } from "@rakazo/core";
 import type { MediaJob, PrismaClient, ThreadEvents } from "@rakazo/db";
@ -160,7 +162,17 @@ function issuesText(error: z.ZodError): string {
    .join("; ");
 }

-function cardBlock(job: MediaJob, outputs: MediaOutput[]): MediaJobBlock {
+/** What a write adds to the card: stored outputs and platforms the job did not render. */
+interface CardAdditions {
+  outputs?: MediaOutput[];
+  skipped?: MediaSkippedTarget[];
+}
+
+function cardBlock(
+  job: MediaJob,
+  outputs: MediaOutput[],
+  skipped: MediaSkippedTarget[] = [],
+): MediaJobBlock {
  return {
    kind: "media",
    jobId: job.id,
@ -170,6 +182,7 @@ function cardBlock(job: MediaJob, outputs: MediaOutput[]): MediaJobBlock {
    ...(job.progress === null ? {} : { progress: job.progress }),
    ...(job.error === null ? {} : { error: job.error }),
    outputs,
+    ...(skipped.length ? { skipped } : {}),
  };
 }

@ -346,8 +359,9 @@ export function createMediaRuntime(
  const writeCard = async (
    tx: Prisma.TransactionClient,
    job: MediaJob,
-    appended: MediaOutput[] = [],
+    added: CardAdditions = {},
  ): Promise<{ exists: boolean; seq?: number; outputs: MediaOutput[] }> => {
+    const appended = added.outputs ?? [];
    if (!job.messageId) return { exists: false, outputs: appended };
    const message = await tx.message.findFirst({
      where: { id: job.messageId, threadId: job.threadId },
@ -356,7 +370,16 @@ export function createMediaRuntime(
    if (!message) return { exists: false, outputs: appended };
    const previous = mediaBlockOf(message.blocks, job.id);
    const outputs = [...(previous?.outputs ?? []), ...appended];
-    const next = cardBlock(job, outputs);
+    // A recovered job runs again, so the newest reason per platform replaces an earlier one.
+    const skipped = [
+      ...new Map(
+        [...(previous?.skipped ?? []), ...(added.skipped ?? [])].map((entry) => [
+          entry.platform,
+          entry,
+        ]),
+      ).values(),
+    ];
+    const next = cardBlock(job, outputs, skipped);
    const current = Array.isArray(message.blocks) ? (message.blocks as MessageBlock[]) : [];
    const blocks = previous
      ? current.map((block) => (block === previous ? next : block))
@ -386,7 +409,7 @@ export function createMediaRuntime(
    jobId: string,
    token: string | null,
    data: Prisma.MediaJobUpdateManyMutationInput,
-    appended: MediaOutput[] = [],
+    added: CardAdditions = {},
  ) => {
    const committed = await withTransactionRetry(() =>
      deps.prisma.$transaction(async (tx) => {
@ -408,7 +431,7 @@ export function createMediaRuntime(
        const updated = await tx.mediaJob.updateMany({ where: fence, data });
        if (!updated.count) return null;
        const job = await tx.mediaJob.findUniqueOrThrow({ where: { id: jobId } });
-        const card = await writeCard(tx, job, appended);
+        const card = await writeCard(tx, job, added);
        return { job, card };
      }),
    );
@ -801,10 +824,15 @@ export function createMediaRuntime(
            ...(posterArtifactId ? { posterArtifactId } : {}),
            ...(parent ? { parentArtifactId: parent.id } : {}),
            ...(file.preset ? { preset: file.preset } : {}),
+            ...(file.platform ? { platform: file.platform } : {}),
+            ...(file.check ? { check: file.check } : {}),
          };
-          const written = await updateJob(jobId, token, { outputArtifactIds: { push: stored } }, [
-            output,
-          ]);
+          const written = await updateJob(
+            jobId,
+            token,
+            { outputArtifactIds: { push: stored } },
+            { outputs: [output] },
+          );
          if (!written) {
            abort("lease");
            throw new Error("Media job lost its lease");
@ -816,6 +844,17 @@ export function createMediaRuntime(
          throw error;
        }
      },
+      addSkipped: async (target) => {
+        signal.throwIfAborted();
+        const written = await updateJob(
+          jobId,
+          token,
+          { updatedAt: new Date() },
+          { skipped: [MediaSkippedTargetSchema.parse(target)] },
+        );
+        if (!written) abort("lease");
+        else if (!written.card.exists) abort("abandoned");
+      },
    };

    try {
--- a/packages/adapters/src/media/ffmpeg.test.ts
+++ b/packages/adapters/src/media/ffmpeg.test.ts
@ -10,7 +10,9 @@ import {
  FfmpegError,
  ffmpegInputArgs,
  ffmpegSeconds,
+  measureLoudness,
  packetDurationMs,
+  parseLoudnormOutput,
  parseProbeOutput,
  probeMedia,
  renderPoster,
@ -18,6 +20,7 @@ import {
 } from "./ffmpeg.js";
 import type { TestClips } from "./media-test-support.js";
 import { createTestClips } from "./media-test-support.js";
+import { planLoudnessFix } from "./video-edit-plan.js";

 const ffmpeg = await detectFfmpeg();

@ -73,6 +76,18 @@ describe("probe parsing", () => {
    });
  });

+  it("reads the stream's average bitrate when the container records it", () => {
+    const probe = parseProbeOutput(
+      JSON.stringify({
+        format: { duration: "3" },
+        streams: [
+          stream({ width: 1080, height: 1920, avg_frame_rate: "30/1", bit_rate: "522994" }),
+        ],
+      }),
+    );
+    expect(probe.video?.bitRateKbps).toBe(523);
+  });
+
  it("reads legacy rotate tags, skips cover art and falls back to stream durations", () => {
    const probe = parseProbeOutput(
      JSON.stringify({
@ -108,6 +123,40 @@ describe("probe parsing", () => {
  });
 });

+describe("loudness parsing", () => {
+  it("reads loudnorm's JSON block from the end of the log", () => {
+    const log = [
+      "Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'file:out.mp4':",
+      "[Parsed_loudnorm_0 @ 0x5555] ",
+      "{",
+      '\t"input_i" : "-17.42",',
+      '\t"input_tp" : "-3.10",',
+      '\t"input_lra" : "5.20",',
+      '\t"input_thresh" : "-27.71",',
+      '\t"output_i" : "-14.02",',
+      '\t"normalization_type" : "dynamic",',
+      '\t"target_offset" : "0.02"',
+      "}",
+    ].join("\n");
+    expect(parseLoudnormOutput(log)).toEqual({
+      integratedLufs: -17.42,
+      truePeakDb: -3.1,
+      rangeLu: 5.2,
+      thresholdLufs: -27.71,
+      offsetLu: 0.02,
+    });
+  });
+
+  it("reads digital silence as minus infinity and refuses a log without numbers", () => {
+    const silent = parseLoudnormOutput(
+      '{"input_i":"-inf","input_tp":"-inf","input_lra":"0.00","input_thresh":"-70.00","target_offset":"inf"}',
+    );
+    expect(silent?.integratedLufs).toBe(Number.NEGATIVE_INFINITY);
+    expect(parseLoudnormOutput("Conversion failed!")).toBeNull();
+    expect(parseLoudnormOutput('{"input_i":"-14.0"}')).toBeNull();
+  });
+});
+
 describe("ffmpeg arguments", () => {
  it("opens inputs through the file protocol with the demuxer of their MIME type", () => {
    expect(
@ -151,6 +200,28 @@ describe.skipIf(!ffmpeg)("ffmpeg integration", () => {
    expect(silent.video).toMatchObject({ width: 180, height: 320 });
  });

+  it("measures loudness and brings it to the target with a linear second pass", async () => {
+    const target = { integratedLufs: -14, truePeakDb: -1 };
+    const before = await measureLoudness(clips.landscape, target, { mimeType: "video/mp4" });
+    // The generated tone sits well below the streaming target.
+    expect(before.integratedLufs).toBeLessThan(-18);
+    const fixed = join(clips.dir, "loudness-fixed.mp4");
+    await runFfmpeg(
+      planLoudnessFix({
+        inputPath: clips.landscape,
+        outputPath: fixed,
+        durationMs: 3000,
+        target,
+        measured: before,
+      }),
+    );
+    const after = await measureLoudness(fixed, target, { mimeType: "video/mp4" });
+    expect(Math.abs(after.integratedLufs - target.integratedLufs)).toBeLessThan(1);
+    const probe = await probeMedia(fixed, { mimeType: "video/mp4" });
+    expect(probe.video).toMatchObject({ codec: "h264", width: 320, height: 180 });
+    expect(Math.abs(probe.durationMs - 3000)).toBeLessThan(50);
+  });
+
  it("refuses a playlist disguised as an MP4 instead of following its URLs", async () => {
    const playlist = join(clips.dir, "playlist.mp4");
    await writeFile(
--- a/packages/adapters/src/media/ffmpeg.ts
+++ b/packages/adapters/src/media/ffmpeg.ts
@ -27,6 +27,8 @@ export interface MediaProbe {
    fps: number;
    /** Pixel aspect ratio of the displayed frame; 1 for square pixels. */
    sampleAspectRatio: number;
+    /** Average bitrate of the stream when the container records it. */
+    bitRateKbps?: number;
  };
  audio?: { codec: string; sampleRate: number; channels: number };
  hasAudio: boolean;
@ -212,6 +214,7 @@ interface ProbeStream {
  sample_rate?: string;
  channels?: number;
  duration?: string;
+  bit_rate?: string;
  disposition?: { attached_pic?: number };
  tags?: { rotate?: string };
  side_data_list?: { rotation?: number }[];
@ -265,6 +268,7 @@ function probeVideo(stream: ProbeStream, width: number, height: number) {
  const sideways = rotation === 90 || rotation === 270;
  const sar = ratio(stream.sample_aspect_ratio, ":") || 1;
  const fps = ratio(stream.avg_frame_rate, "/") || ratio(stream.r_frame_rate, "/");
+  const bitRate = positive(Number(stream.bit_rate));
  return {
    codec: stream.codec_name ?? "",
    width: sideways ? height : width,
@ -272,6 +276,7 @@ function probeVideo(stream: ProbeStream, width: number, height: number) {
    rotation,
    fps: fps > 0 && fps <= MAX_PLAUSIBLE_FPS ? fps : 0,
    sampleAspectRatio: sideways ? 1 / sar : sar,
+    ...(bitRate ? { bitRateKbps: Math.round(bitRate / 1000) } : {}),
  };
 }

@ -505,6 +510,94 @@ export async function extractAudio(
  );
 }

+/** EBU R128 values of a file's first audio track, as ffmpeg's loudnorm filter measures them. */
+export interface LoudnessMeasurement {
+  /** Integrated loudness in LUFS; -Infinity for digital silence. */
+  integratedLufs: number;
+  truePeakDb: number;
+  rangeLu: number;
+  thresholdLufs: number;
+  /** Gain loudnorm's second pass adds after limiting, for the targets it measured against. */
+  offsetLu: number;
+}
+
+const LOUDNESS_TIMEOUT_MS = 10 * 60_000;
+
+/** loudnorm's filter string: the target, and the first pass's numbers for a linear second pass. */
+export function loudnormFilter(
+  target: { integratedLufs: number; truePeakDb: number },
+  measured?: LoudnessMeasurement,
+): string {
+  const options = [
+    `I=${target.integratedLufs}`,
+    `TP=${target.truePeakDb}`,
+    // A wide loudness range keeps loudnorm linear (no pumping) for most speech and music.
+    "LRA=11",
+    ...(measured
+      ? [
+          `measured_I=${measured.integratedLufs}`,
+          `measured_TP=${measured.truePeakDb}`,
+          `measured_LRA=${measured.rangeLu}`,
+          `measured_thresh=${measured.thresholdLufs}`,
+          `offset=${measured.offsetLu}`,
+          "linear=true",
+        ]
+      : []),
+  ];
+  return `loudnorm=${options.join(":")}`;
+}
+
+/** Measures the loudness of a file with an audio track against a target. */
+export async function measureLoudness(
+  input: string,
+  target: { integratedLufs: number; truePeakDb: number },
+  options: { signal?: AbortSignal; mimeType?: string } = {},
+): Promise<LoudnessMeasurement> {
+  const { ffmpegPath } = await requireFfmpeg();
+  const result = await capture(
+    ffmpegPath,
+    [
+      ...["-hide_banner", "-nostdin", "-nostats", "-loglevel", "info"],
+      ...ffmpegInputArgs(input, { mimeType: options.mimeType }),
+      ...["-map", "0:a:0", "-af", `${loudnormFilter(target)}:print_format=json`],
+      ...["-f", "null", "-"],
+    ],
+    { signal: options.signal, timeoutMs: LOUDNESS_TIMEOUT_MS },
+  );
+  if (result.code !== 0) throw ffmpegFailure("ffmpeg", result.code, result.stderr);
+  const measured = parseLoudnormOutput(result.stderr);
+  if (!measured) throw new Error("ffmpeg did not report the loudness.");
+  return measured;
+}
+
+/** Reads the JSON block loudnorm prints with print_format=json at the end of its log. */
+export function parseLoudnormOutput(log: string): LoudnessMeasurement | null {
+  const start = log.lastIndexOf("{");
+  const end = log.lastIndexOf("}");
+  if (start < 0 || end < start) return null;
+  let data: Record<string, string>;
+  try {
+    data = JSON.parse(log.slice(start, end + 1)) as Record<string, string>;
+  } catch {
+    return null;
+  }
+  const value = (key: string) => {
+    const text = data[key]?.trim();
+    // Digital silence measures as -inf, and its offset as inf.
+    if (text === "-inf") return Number.NEGATIVE_INFINITY;
+    if (text === "inf") return Number.POSITIVE_INFINITY;
+    return text ? Number(text) : Number.NaN;
+  };
+  const measured = {
+    integratedLufs: value("input_i"),
+    truePeakDb: value("input_tp"),
+    rangeLu: value("input_lra"),
+    thresholdLufs: value("input_thresh"),
+    offsetLu: value("target_offset"),
+  };
+  return Object.values(measured).some(Number.isNaN) ? null : measured;
+}
+
 /** Writes one JPEG frame at atMs (default 0), falling back to the first frame past the end. */
 export async function renderPoster(
  input: string,
--- a/packages/adapters/src/media/image-operations.test.ts
+++ b/packages/adapters/src/media/image-operations.test.ts
@ -103,6 +103,7 @@ async function run(
      };
      return output;
    },
+    addSkipped: async () => undefined,
  };
  const result = await operation(name).handler.run(context);
  return { result, outputs, progress };
--- a/packages/adapters/src/media/media-test-support.ts
+++ b/packages/adapters/src/media/media-test-support.ts
@ -2,7 +2,7 @@ import { copyFile, mkdtemp, stat, writeFile } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import type { MediaJobContext, MediaJobInputFile, MediaJobOutputFile } from "@rakazo/adapter-kit";
-import type { MediaOutput, MediaOutputKind } from "@rakazo/contracts";
+import type { MediaOutput, MediaOutputKind, MediaSkippedTarget } from "@rakazo/contracts";
 import { attachmentKindOf } from "@rakazo/contracts";
 import { runFfmpeg } from "./ffmpeg.js";

@ -50,12 +50,13 @@ export interface TestArtifact {
  kind?: MediaOutputKind;
 }

-/** A MediaJobContext over local files that records progress and outputs. */
+/** A MediaJobContext over local files that records progress, outputs and skipped platforms. */
 export async function fakeMediaJobContext(input: unknown, artifacts: Record<string, TestArtifact>) {
  const tempDir = await mkdtemp(join(tmpdir(), "evoo-media-job-"));
  const controller = new AbortController();
  const progress: number[] = [];
  const outputs: (MediaJobOutputFile & { size: number; posterSize?: number })[] = [];
+  const skipped: MediaSkippedTarget[] = [];
  const context: MediaJobContext = {
    jobId: "job-1",
    spaceId: "space-1",
@ -99,8 +100,13 @@ export async function fakeMediaJobContext(input: unknown, artifacts: Record<stri
        ...(file.posterPath ? { posterArtifactId: `poster-${index}` } : {}),
        ...(file.parentArtifactId ? { parentArtifactId: file.parentArtifactId } : {}),
        ...(file.preset ? { preset: file.preset } : {}),
+        ...(file.platform ? { platform: file.platform } : {}),
+        ...(file.check ? { check: file.check } : {}),
      };
    },
+    addSkipped: async (target) => {
+      skipped.push(target);
+    },
  };
-  return { context, controller, progress, outputs, tempDir };
+  return { context, controller, progress, outputs, skipped, tempDir };
 }
--- a/packages/adapters/src/media/platform-export.test.ts
+++ b/packages/adapters/src/media/platform-export.test.ts
@ -0,0 +1,188 @@
+import { MEDIA_PLATFORM_PROFILES } from "@rakazo/contracts";
+import { describe, expect, it } from "vitest";
+import type { ExportMeasurement } from "./platform-export.js";
+import {
+  BITRATE_TOLERANCE,
+  checkExport,
+  DURATION_TOLERANCE_MS,
+  describeSkipped,
+  durationIssues,
+  LOUDNESS_TOLERANCE_LU,
+  MIN_VIDEO_KBPS,
+  needsLoudnessFix,
+  platformTarget,
+  sizeBudgetKbps,
+  sizeFixKbps,
+  TRUE_PEAK_TOLERANCE_DB,
+} from "./platform-export.js";
+
+const tiktok = MEDIA_PLATFORM_PROFILES.tiktok;
+
+/** A clean 30 s TikTok render; tests override what they examine. */
+function measured(overrides: Partial<ExportMeasurement> = {}): ExportMeasurement {
+  return {
+    width: 1080,
+    height: 1920,
+    fps: 30,
+    codec: "h264",
+    durationMs: 30_000,
+    sizeBytes: 20_000_000,
+    videoKbps: 5000,
+    loudness: {
+      integratedLufs: -14.2,
+      truePeakDb: -1.3,
+      rangeLu: 4,
+      thresholdLufs: -24.5,
+      offsetLu: 0.1,
+    },
+    ...overrides,
+  };
+}
+
+function loudness(integratedLufs: number, truePeakDb = -2) {
+  return { integratedLufs, truePeakDb, rangeLu: 4, thresholdLufs: -30, offsetLu: 0 };
+}
+
+describe("platform targets", () => {
+  it("renders to the profile and caps the bitrate below its size limit for long videos", () => {
+    expect(platformTarget(tiktok, "blur", 30_000)).toEqual({
+      width: 1080,
+      height: 1920,
+      fit: "blur",
+      maxFps: 30,
+      maxBitrateKbps: 8000,
+      integratedLufs: -14,
+      truePeakDb: -1,
+    });
+    // 287 MB over 10 minutes leaves about 3.6 Mbps of video after headroom and audio.
+    const tenMinutes = platformTarget(tiktok, "crop", 600_000).maxBitrateKbps;
+    expect(tenMinutes).toBe(sizeBudgetKbps(tiktok, 600_000));
+    expect(tenMinutes).toBeGreaterThan(3000);
+    expect(tenMinutes).toBeLessThan(3700);
+    expect(tenMinutes * 600 + 160 * 600).toBeLessThan(287 * 8000);
+    expect(sizeBudgetKbps(tiktok, 1e9)).toBe(MIN_VIDEO_KBPS);
+  });
+});
+
+describe("duration limits", () => {
+  it("refuses videos past the limits, with a small tolerance for container rounding", () => {
+    expect(durationIssues(tiktok, 600_000 + DURATION_TOLERANCE_MS)).toEqual([]);
+    expect(durationIssues(tiktok, 720_000)).toEqual([
+      { code: "too_long", maxMs: 600_000, actualMs: 720_000 },
+    ]);
+    expect(durationIssues(tiktok, 3000 - DURATION_TOLERANCE_MS)).toEqual([]);
+    expect(durationIssues(tiktok, 2000)).toEqual([
+      { code: "too_short", minMs: 3000, actualMs: 2000 },
+    ]);
+  });
+
+  it("words a skipped platform for the bot with what to do about it", () => {
+    expect(describeSkipped(tiktok, durationIssues(tiktok, 720_000))).toBe(
+      "Not exported for TikTok: 720 s is longer than its 600 s limit; trim the video first.",
+    );
+    expect(describeSkipped(tiktok, durationIssues(tiktok, 1500))).toBe(
+      "Not exported for TikTok: 1.5 s is shorter than its 3 s minimum; use a longer video.",
+    );
+  });
+});
+
+describe("platform check", () => {
+  it("passes a render within every tolerance", () => {
+    expect(
+      checkExport(
+        tiktok,
+        measured({
+          videoKbps: 8000 * (1 + BITRATE_TOLERANCE),
+          fps: 30.2,
+          loudness: loudness(-14 - LOUDNESS_TOLERANCE_LU, -1 + TRUE_PEAK_TOLERANCE_DB),
+        }),
+      ),
+    ).toEqual({ status: "pass", issues: [] });
+  });
+
+  it("warns about what the platform would degrade", () => {
+    expect(
+      checkExport(
+        tiktok,
+        measured({
+          width: 720,
+          height: 1280,
+          fps: 60,
+          videoKbps: 9500,
+          loudness: loudness(-17.26, -0.2),
+        }),
+      ),
+    ).toEqual({
+      status: "warn",
+      issues: [
+        {
+          code: "resolution_mismatch",
+          width: 1080,
+          height: 1920,
+          actualWidth: 720,
+          actualHeight: 1280,
+        },
+        { code: "fps_mismatch", maxFps: 30, actualFps: 60 },
+        { code: "bitrate_high", maxKbps: 8000, actualKbps: 9500 },
+        { code: "loudness_off", targetLufs: -14, actualLufs: -17.3 },
+        { code: "true_peak_high", maxDb: -1, actualDb: -0.2 },
+      ],
+    });
+  });
+
+  it("fails what the platform would reject, most severe first", () => {
+    const check = checkExport(
+      tiktok,
+      measured({ codec: "hevc", sizeBytes: 300_456_789, loudness: loudness(-20) }),
+    );
+    expect(check.status).toBe("fail");
+    expect(check.issues).toEqual([
+      { code: "file_too_large", maxMb: 287, actualMb: 300.5 },
+      { code: "codec_mismatch" },
+      { code: "loudness_off", targetLufs: -14, actualLufs: -20 },
+    ]);
+    expect(checkExport(tiktok, measured({ durationMs: 601_000 })).issues[0]).toEqual({
+      code: "too_long",
+      maxMs: 600_000,
+      actualMs: 601_000,
+    });
+  });
+
+  it("does not judge the loudness of silent or missing audio, or an unknown frame rate", () => {
+    expect(checkExport(tiktok, measured({ loudness: null, fps: 0 })).status).toBe("pass");
+    expect(
+      checkExport(tiktok, measured({ loudness: loudness(Number.NEGATIVE_INFINITY) })).status,
+    ).toBe("pass");
+    expect(checkExport(tiktok, measured({ loudness: loudness(-65) })).status).toBe("pass");
+  });
+});
+
+describe("automatic fixes", () => {
+  it("re-encodes an oversized file once at a bitrate scaled from what it averaged", () => {
+    expect(sizeFixKbps(tiktok, measured(), 8000)).toBeNull();
+    // 330 MB at 4400 kbps average: scale by 287/330 and keep 10% headroom.
+    const lower = sizeFixKbps(tiktok, measured({ sizeBytes: 330_000_000, videoKbps: 4400 }), 8000);
+    expect(lower).toBe(Math.floor(4400 * (287 / 330) * 0.9));
+    // Without a stream bitrate, the file size and length give the average.
+    expect(
+      sizeFixKbps(
+        tiktok,
+        measured({ sizeBytes: 330_000_000, videoKbps: undefined, durationMs: 600_000 }),
+        8000,
+      ),
+    ).toBe(Math.floor((4400 - 160) * (287 / 330) * 0.9));
+    // Nothing lower is left to try.
+    expect(
+      sizeFixKbps(tiktok, measured({ sizeBytes: 330_000_000, videoKbps: 200 }), MIN_VIDEO_KBPS),
+    ).toBeNull();
+  });
+
+  it("re-normalizes audible audio that missed the loudness target by more than the tolerance", () => {
+    expect(needsLoudnessFix(tiktok, measured())).toBe(false);
+    expect(needsLoudnessFix(tiktok, measured({ loudness: loudness(-16) }))).toBe(false);
+    expect(needsLoudnessFix(tiktok, measured({ loudness: loudness(-16.5) }))).toBe(true);
+    expect(needsLoudnessFix(tiktok, measured({ loudness: loudness(-10) }))).toBe(true);
+    expect(needsLoudnessFix(tiktok, measured({ loudness: null }))).toBe(false);
+    expect(needsLoudnessFix(tiktok, measured({ loudness: loudness(-70) }))).toBe(false);
+  });
+});
--- a/packages/adapters/src/media/platform-export.ts
+++ b/packages/adapters/src/media/platform-export.ts
@ -0,0 +1,221 @@
+import type { MediaCheck, MediaCheckIssue, MediaFit, PlatformProfile } from "@rakazo/contracts";
+import type { LoudnessMeasurement } from "./ffmpeg.js";
+import type { ExportTarget } from "./video-edit-plan.js";
+import { AUDIO_BITRATE_KBPS } from "./video-edit-plan.js";
+
+/**
+ * Pure rules of a platform export: what to render, whether the result fits the platform, and
+ * which one-time fix to try when it does not.
+ */
+
+/** Container durations differ from the cut by a few audio frames. */
+export const DURATION_TOLERANCE_MS = 100;
+/** Average video bitrate above the platform's cap by more than this share earns a warning. */
+export const BITRATE_TOLERANCE = 0.1;
+/** Frame rate above the platform's cap by more than this share earns a warning. */
+export const FPS_TOLERANCE = 0.01;
+/** Integrated loudness this far from the target is re-normalized once, then warned about. */
+export const LOUDNESS_TOLERANCE_LU = 2;
+/** True peak above the platform's ceiling by more than this earns a warning (AAC adds a little). */
+export const TRUE_PEAK_TOLERANCE_DB = 0.5;
+/** Integrated loudness below this is silence: nothing to normalize or check. */
+export const SILENCE_LUFS = -60;
+/** Share of the file size limit the first encode budgets for, and a re-encode after an overshoot. */
+export const SIZE_HEADROOM = 0.95;
+export const SIZE_FIX_HEADROOM = 0.9;
+/** Below this the picture falls apart; a file that still does not fit fails the check instead. */
+export const MIN_VIDEO_KBPS = 300;
+const BYTES_PER_MB = 1_000_000;
+
+const FAILING_CODES = new Set<MediaCheckIssue["code"]>([
+  "too_long",
+  "too_short",
+  "file_too_large",
+  "codec_mismatch",
+]);
+
+/** What a rendered file measured. */
+export interface ExportMeasurement {
+  width: number;
+  height: number;
+  /** 0 when unknown. */
+  fps: number;
+  codec: string;
+  durationMs: number;
+  sizeBytes: number;
+  videoKbps?: number;
+  /** Null without an audio track. */
+  loudness: LoudnessMeasurement | null;
+}
+
+/** Highest video bitrate that keeps a file of this length under the platform's size limit. */
+export function sizeBudgetKbps(
+  profile: PlatformProfile,
+  durationMs: number,
+  headroom = SIZE_HEADROOM,
+): number {
+  const totalKbps = (profile.video.maxFileSizeMb * BYTES_PER_MB * 8) / Math.max(1, durationMs);
+  return Math.max(MIN_VIDEO_KBPS, Math.floor(totalKbps * headroom - AUDIO_BITRATE_KBPS));
+}
+
+export function platformTarget(
+  profile: PlatformProfile,
+  fit: MediaFit,
+  durationMs: number,
+): ExportTarget {
+  return {
+    width: profile.video.width,
+    height: profile.video.height,
+    fit,
+    maxFps: profile.video.fps,
+    maxBitrateKbps: Math.min(profile.video.maxBitrateKbps, sizeBudgetKbps(profile, durationMs)),
+    integratedLufs: profile.audio.targetLufs,
+    truePeakDb: profile.audio.truePeakDb,
+  };
+}
+
+/** Why a video of this length cannot go on the platform; empty when it can. */
+export function durationIssues(profile: PlatformProfile, durationMs: number): MediaCheckIssue[] {
+  const { hardMinMs, hardMaxMs } = profile.duration;
+  if (durationMs > hardMaxMs + DURATION_TOLERANCE_MS) {
+    return [{ code: "too_long", maxMs: hardMaxMs, actualMs: Math.round(durationMs) }];
+  }
+  if (durationMs < hardMinMs - DURATION_TOLERANCE_MS) {
+    return [{ code: "too_short", minMs: hardMinMs, actualMs: Math.round(durationMs) }];
+  }
+  return [];
+}
+
+function audible(loudness: LoudnessMeasurement | null): loudness is LoudnessMeasurement {
+  return loudness !== null && loudness.integratedLufs > SILENCE_LUFS;
+}
+
+/** Compares a rendered file with the platform's limits; failing issues come first. */
+export function checkExport(profile: PlatformProfile, measured: ExportMeasurement): MediaCheck {
+  const { video, audio } = profile;
+  const issues: MediaCheckIssue[] = [...durationIssues(profile, measured.durationMs)];
+  const maxBytes = video.maxFileSizeMb * BYTES_PER_MB;
+  if (measured.sizeBytes > maxBytes) {
+    issues.push({
+      code: "file_too_large",
+      maxMb: video.maxFileSizeMb,
+      actualMb: round(measured.sizeBytes / BYTES_PER_MB, 1),
+    });
+  }
+  if (measured.codec !== video.codec) issues.push({ code: "codec_mismatch" });
+  if (measured.width !== video.width || measured.height !== video.height) {
+    issues.push({
+      code: "resolution_mismatch",
+      width: video.width,
+      height: video.height,
+      actualWidth: measured.width,
+      actualHeight: measured.height,
+    });
+  }
+  if (measured.fps > video.fps * (1 + FPS_TOLERANCE)) {
+    issues.push({ code: "fps_mismatch", maxFps: video.fps, actualFps: round(measured.fps, 2) });
+  }
+  if (
+    measured.videoKbps !== undefined &&
+    measured.videoKbps > video.maxBitrateKbps * (1 + BITRATE_TOLERANCE)
+  ) {
+    issues.push({
+      code: "bitrate_high",
+      maxKbps: video.maxBitrateKbps,
+      actualKbps: Math.round(measured.videoKbps),
+    });
+  }
+  if (audible(measured.loudness)) {
+    const { integratedLufs, truePeakDb } = measured.loudness;
+    if (Math.abs(integratedLufs - audio.targetLufs) > LOUDNESS_TOLERANCE_LU) {
+      issues.push({
+        code: "loudness_off",
+        targetLufs: audio.targetLufs,
+        actualLufs: round(integratedLufs, 1),
+      });
+    }
+    if (truePeakDb > audio.truePeakDb + TRUE_PEAK_TOLERANCE_DB) {
+      issues.push({
+        code: "true_peak_high",
+        maxDb: audio.truePeakDb,
+        actualDb: round(truePeakDb, 1),
+      });
+    }
+  }
+  const failing = issues.filter((issue) => FAILING_CODES.has(issue.code));
+  const warning = issues.filter((issue) => !FAILING_CODES.has(issue.code));
+  return {
+    status: failing.length ? "fail" : warning.length ? "warn" : "pass",
+    issues: [...failing, ...warning],
+  };
+}
+
+/**
+ * The lower bitrate cap for one re-encode of a file over the size limit, scaled from what the
+ * file actually averaged; null when it fits or a lower cap would not help.
+ */
+export function sizeFixKbps(
+  profile: PlatformProfile,
+  measured: ExportMeasurement,
+  currentKbps: number,
+): number | null {
+  const maxBytes = profile.video.maxFileSizeMb * BYTES_PER_MB;
+  if (measured.sizeBytes <= maxBytes) return null;
+  const averageKbps =
+    measured.videoKbps ??
+    (measured.sizeBytes * 8) / Math.max(1, measured.durationMs) - AUDIO_BITRATE_KBPS;
+  const scaled = Math.min(currentKbps, averageKbps) * (maxBytes / measured.sizeBytes);
+  const next = Math.max(MIN_VIDEO_KBPS, Math.floor(scaled * SIZE_FIX_HEADROOM));
+  return next < currentKbps ? next : null;
+}
+
+/** Whether one more loudness pass is worth it: the audio is audible and off the target. */
+export function needsLoudnessFix(profile: PlatformProfile, measured: ExportMeasurement): boolean {
+  return (
+    audible(measured.loudness) &&
+    Math.abs(measured.loudness.integratedLufs - profile.audio.targetLufs) > LOUDNESS_TOLERANCE_LU
+  );
+}
+
+/** An issue in a few English words for the bot's summary; the web words them itself. */
+export function describeIssue(issue: MediaCheckIssue): string {
+  switch (issue.code) {
+    case "too_long":
+      return `${seconds(issue.actualMs)} is longer than its ${seconds(issue.maxMs)} limit`;
+    case "too_short":
+      return `${seconds(issue.actualMs)} is shorter than its ${seconds(issue.minMs)} minimum`;
+    case "file_too_large":
+      return `${issue.actualMb} MB is larger than its ${issue.maxMb} MB limit`;
+    case "bitrate_high":
+      return `video bitrate ${issue.actualKbps} kbps is above its ${issue.maxKbps} kbps`;
+    case "loudness_off":
+      return `loudness ${issue.actualLufs} LUFS, target ${issue.targetLufs} LUFS`;
+    case "true_peak_high":
+      return `true peak ${issue.actualDb} dBTP is above its ${issue.maxDb} dBTP`;
+    case "resolution_mismatch":
+      return `frame ${issue.actualWidth}×${issue.actualHeight} instead of ${issue.width}×${issue.height}`;
+    case "fps_mismatch":
+      return `${issue.actualFps} fps is above its ${issue.maxFps} fps`;
+    case "codec_mismatch":
+      return "video is not H.264";
+  }
+}
+
+/** "Not exported for TikTok: 720 s is longer than its 600 s limit; trim the video first." */
+export function describeSkipped(
+  profile: Pick<PlatformProfile, "name">,
+  issues: readonly MediaCheckIssue[],
+): string {
+  const advice = issues.some((issue) => issue.code === "too_short")
+    ? "use a longer video"
+    : "trim the video first";
+  return `Not exported for ${profile.name}: ${issues.map(describeIssue).join("; ")}; ${advice}.`;
+}
+
+function seconds(ms: number): string {
+  return `${Number((ms / 1000).toFixed(1))} s`;
+}
+
+function round(value: number, digits: number): number {
+  return Number(value.toFixed(digits));
+}
--- a/packages/adapters/src/media/transcription.test.ts
+++ b/packages/adapters/src/media/transcription.test.ts
@ -150,6 +150,7 @@ async function jobContext(source: Omit<MediaJobInputFile, "path">, input: unknow
      outputs.push({ ...file, body: await readFile(file.path, "utf8") });
      return { artifactId: `out-${outputs.length}` } as MediaOutput;
    },
+    addSkipped: async () => undefined,
  };
  return { context, outputs, progress };
 }
--- a/packages/adapters/src/media/video-edit-plan.test.ts
+++ b/packages/adapters/src/media/video-edit-plan.test.ts
@ -1,8 +1,10 @@
 import type { EditVideoStep } from "@rakazo/contracts";
+import { MEDIA_PLATFORM_PROFILES } from "@rakazo/contracts";
 import { describe, expect, it } from "vitest";
 import type { MediaProbe } from "./ffmpeg.js";
+import { platformTarget } from "./platform-export.js";
 import type { PlanInput } from "./video-edit-plan.js";
-import { atempoFilters, planVideoEdit, subtitleStyle } from "./video-edit-plan.js";
+import { atempoFilters, planLoudnessFix, planVideoEdit, subtitleStyle } from "./video-edit-plan.js";

 function probe(
  overrides: Partial<NonNullable<MediaProbe["video"]>> & {
@ -298,3 +300,83 @@ describe("planVideoEdit", () => {
    expect(graphOf(evened.args)).toBe("[0:v:0]crop=720:404:0:0,format=yuv420p[v1]");
  });
 });
+
+describe("platform export plans", () => {
+  const fast = { ...source, probe: probe({ fps: 120, durationMs: 20_000 }) };
+
+  it.each(Object.values(MEDIA_PLATFORM_PROFILES))(
+    "renders $name to its frame, frame rate, bitrate and loudness",
+    (profile) => {
+      const target = platformTarget(profile, "crop", 20_000);
+      const result = planVideoEdit({
+        source: fast,
+        steps: [],
+        target,
+        outputPath: "/jobs/1/output.mp4",
+      });
+      const { width, height, fps, maxBitrateKbps } = profile.video;
+      const graph = graphOf(result.args);
+      expect(graph).toContain(`fps=${fps}`);
+      expect(graph).toMatch(new RegExp(`scale=${width}:${height}[,:]`));
+      expect(graph).toContain(
+        `loudnorm=I=${profile.audio.targetLufs}:TP=${profile.audio.truePeakDb}:LRA=11,atrim=end=20`,
+      );
+      expect(target.maxBitrateKbps).toBe(maxBitrateKbps);
+      const maxrate = result.args.indexOf("-maxrate");
+      expect(result.args.slice(maxrate, maxrate + 4)).toEqual([
+        "-maxrate",
+        `${maxBitrateKbps}k`,
+        "-bufsize",
+        `${maxBitrateKbps * 2}k`,
+      ]);
+      expect(result).toMatchObject({ kind: "video", width, height, durationMs: 20_000 });
+    },
+  );
+
+  it("keeps a slower frame rate, fits by the export's fit, and skips loudness without audio", () => {
+    const target = platformTarget(MEDIA_PLATFORM_PROFILES.tiktok, "pad", 10_000);
+    const graph = graphOf(
+      planVideoEdit({
+        source: { ...source, probe: probe({ fps: 24, hasAudio: false }) },
+        steps: [],
+        target,
+        outputPath: "/jobs/1/output.mp4",
+      }).args,
+    );
+    expect(graph).not.toContain("fps=");
+    expect(graph).toContain("pad=1080:1920:(ow-iw)/2:(oh-ih)/2:color=black");
+    expect(graph).not.toContain("loudnorm");
+    // An unknown (variable) frame rate gets the platform's.
+    const variable = graphOf(
+      planVideoEdit({
+        source: { ...source, probe: probe({ fps: 0 }) },
+        steps: [],
+        target,
+        outputPath: "/jobs/1/output.mp4",
+      }).args,
+    );
+    expect(variable).toContain("fps=30");
+  });
+
+  it("plans a linear second loudness pass that copies the video", () => {
+    const args = planLoudnessFix({
+      inputPath: "/jobs/1/tiktok.mp4",
+      outputPath: "/jobs/1/tiktok-loudness.mp4",
+      durationMs: 12_500,
+      target: { integratedLufs: -14, truePeakDb: -1 },
+      measured: {
+        integratedLufs: -17.4,
+        truePeakDb: -4.2,
+        rangeLu: 5.1,
+        thresholdLufs: -27.6,
+        offsetLu: 0.3,
+      },
+    });
+    expect(args).toContain("file:/jobs/1/tiktok.mp4");
+    expect(graphOf(args)).toBe(
+      "[0:a:0]loudnorm=I=-14:TP=-1:LRA=11:measured_I=-17.4:measured_TP=-4.2:measured_LRA=5.1:measured_thresh=-27.6:offset=0.3:linear=true,atrim=end=12.5,aformat=sample_fmts=fltp:sample_rates=48000:channel_layouts=stereo[a1]",
+    );
+    expect(args.join(" ")).toContain("-map 0:v:0 -map [a1] -c:v copy -c:a aac -b:a 160k");
+    expect(args.at(-1)).toBe("file:/jobs/1/tiktok-loudness.mp4");
+  });
+});
--- a/packages/adapters/src/media/video-edit-plan.ts
+++ b/packages/adapters/src/media/video-edit-plan.ts
@ -1,7 +1,7 @@
 import type { EditVideoStep, MediaFit } from "@rakazo/contracts";
 import { MEDIA_PRESETS } from "@rakazo/contracts";
-import type { MediaProbe } from "./ffmpeg.js";
-import { ffmpegInputArgs, ffmpegSeconds } from "./ffmpeg.js";
+import type { LoudnessMeasurement, MediaProbe } from "./ffmpeg.js";
+import { ffmpegInputArgs, ffmpegSeconds, loudnormFilter } from "./ffmpeg.js";

 /**
 * Turns an ordered list of edit steps into one ffmpeg invocation with a single filter_complex
@ -22,9 +22,22 @@ export interface VideoEditPlanRequest {
  clips?: ReadonlyMap<string, PlanInput>;
  /** Subtitle files named by subtitles steps, by artifact id: safe names relative to ffmpeg's cwd. */
  subtitleFiles?: ReadonlyMap<string, string>;
+  /** A platform's limits, applied after the steps. */
+  target?: ExportTarget;
  outputPath: string;
 }

+/** The frame, frame rate cap, bitrate cap and loudness a platform export is rendered to. */
+export interface ExportTarget {
+  width: number;
+  height: number;
+  fit: MediaFit;
+  maxFps: number;
+  maxBitrateKbps: number;
+  integratedLufs: number;
+  truePeakDb: number;
+}
+
 export interface VideoEditPlan {
  args: string[];
  kind: "video" | "audio";
@ -46,7 +59,8 @@ export const VIDEO_ENCODE_ARGS = [
  "-movflags",
  "+faststart",
 ];
-const AUDIO_ENCODE_ARGS = ["-c:a", "aac", "-b:a", "160k"];
+export const AUDIO_BITRATE_KBPS = 160;
+const AUDIO_ENCODE_ARGS = ["-c:a", "aac", "-b:a", `${AUDIO_BITRATE_KBPS}k`];
 const AUDIO_ONLY_ENCODE_ARGS = ["-c:a", "aac", "-b:a", "192k", "-movflags", "+faststart"];
 /** Location and other camera metadata stay private; chapters do not survive cuts anyway. */
 const STRIP_METADATA_ARGS = ["-map_metadata", "-1", "-map_chapters", "-1"];
@ -229,6 +243,8 @@ export function planVideoEdit(request: VideoEditPlanRequest): VideoEditPlan {
      `poster at ${seconds(posterAt)} s is past the end of the ${seconds(timeline.seconds)} s result.`,
    );
  }
+  const { target } = request;
+  if (target && !audioOnly) applyTarget(graph, timeline, target);
  const durationMs = Math.round(timeline.seconds * 1000);
  const output = `file:${request.outputPath}`;
  if (audioOnly || !timeline.video) {
@ -268,6 +284,7 @@ export function planVideoEdit(request: VideoEditPlanRequest): VideoEditPlan {
      `[${videoOut}]`,
      ...(audioOut ? ["-map", `[${audioOut}]`, ...AUDIO_ENCODE_ARGS] : []),
      ...VIDEO_ENCODE_ARGS,
+      ...(target && !audioOnly ? bitrateCapArgs(target.maxBitrateKbps) : []),
      ...STRIP_METADATA_ARGS,
      "-f",
      "mp4",
@ -281,6 +298,64 @@ export function planVideoEdit(request: VideoEditPlanRequest): VideoEditPlan {
  };
 }

+/**
+ * Fits the result to a platform: frame rate cap, frame size and loudness. Loudness is one
+ * dynamic loudnorm pass, which lands within about 1 LU of the target on most material without
+ * decoding the source twice; the export measures the result and corrects it when it misses.
+ */
+function applyTarget(graph: FilterGraph, timeline: Timeline, target: ExportTarget) {
+  if (timeline.video) {
+    if (!timeline.fps || timeline.fps > target.maxFps + 0.01) {
+      timeline.video.filters.push(`fps=${number(target.maxFps)}`);
+      timeline.fps = target.maxFps;
+    }
+    timeline.video = fitFrame(graph, timeline.video, timeline, target, target.fit);
+  }
+  timeline.width = target.width;
+  timeline.height = target.height;
+  // loudnorm pads its last frame; trim the audio back to the video's length.
+  timeline.audio?.filters.push(
+    loudnormFilter(target),
+    `atrim=end=${ffmpegSeconds(timeline.seconds)}`,
+  );
+}
+
+/** CRF quality, capped so no stretch of the video runs above the platform's bitrate. */
+function bitrateCapArgs(maxBitrateKbps: number): string[] {
+  const kbps = Math.max(1, Math.round(maxBitrateKbps));
+  return ["-maxrate", `${kbps}k`, "-bufsize", `${kbps * 2}k`];
+}
+
+/**
+ * Second loudness pass over a rendered MP4: linear loudnorm with the measured values on the
+ * audio, the video copied as it is.
+ */
+export function planLoudnessFix(request: {
+  inputPath: string;
+  outputPath: string;
+  durationMs: number;
+  target: { integratedLufs: number; truePeakDb: number };
+  measured: LoudnessMeasurement;
+}): string[] {
+  const filters = [
+    loudnormFilter(request.target, request.measured),
+    `atrim=end=${ffmpegSeconds(request.durationMs / 1000)}`,
+    AUDIO_FORMAT,
+  ];
+  return [
+    ...ffmpegInputArgs(request.inputPath, { mimeType: "video/mp4" }),
+    "-filter_complex",
+    `[0:a:0]${filters.join(",")}[a1]`,
+    ...["-map", "0:v:0", "-map", "[a1]", "-c:v", "copy"],
+    ...AUDIO_ENCODE_ARGS,
+    ...["-movflags", "+faststart"],
+    ...STRIP_METADATA_ARGS,
+    "-f",
+    "mp4",
+    `file:${request.outputPath}`,
+  ];
+}
+
 interface Segment {
  start: number;
  end: number;
--- a/packages/adapters/src/media/video-operations.postgres.test.ts
+++ b/packages/adapters/src/media/video-operations.postgres.test.ts
@ -176,6 +176,63 @@ describePostgres("video operations in the media runtime (PostgreSQL + ffmpeg)",
    ]);
  });

+  it("exports for a platform with its check and shows a skipped platform on the card", async () => {
+    const { runtime, scope, store } = await setup();
+    const source = await store(clips.landscape, "holiday.mp4", "video/mp4");
+    const started = await runtime.start({
+      ...scope,
+      operation: "export_video",
+      input: { artifact_id: source, platforms: ["tiktok", "snapchat-spotlight"] },
+    });
+    await runtime.runJob(started.jobId);
+    const job = await runtime.get(started.jobId);
+    expect(job).toMatchObject({ status: "done", title: "TikTok · Snapchat Spotlight" });
+    expect(job?.outputs).toEqual([
+      expect.objectContaining({
+        name: "holiday-tiktok.mp4",
+        platform: "tiktok",
+        width: 1080,
+        height: 1920,
+        check: { status: "pass", issues: [] },
+      }),
+    ]);
+    const stored = await prisma.artifact.findUniqueOrThrow({
+      where: { id: job!.outputs[0]!.artifactId },
+    });
+    expect(stored).toMatchObject({ parentArtifactId: source, width: 1080, height: 1920 });
+    expect(await card(started.messageId, started.jobId)).toMatchObject({
+      status: "done",
+      outputs: job?.outputs,
+      skipped: [
+        {
+          platform: "snapchat-spotlight",
+          issues: [{ code: "too_short", minMs: 5000, actualMs: 3000 }],
+        },
+      ],
+    });
+  });
+
+  it("fails an export that fits none of its platforms and keeps the reason on the card", async () => {
+    const { runtime, scope, store } = await setup();
+    const source = await store(clips.landscape, "short.mp4", "video/mp4");
+    const started = await runtime.start({
+      ...scope,
+      operation: "export_video",
+      input: { artifact_id: source, platforms: ["snapchat-spotlight"] },
+    });
+    await runtime.runJob(started.jobId);
+    expect(await runtime.get(started.jobId)).toMatchObject({
+      status: "failed",
+      error:
+        "Not exported for Snapchat Spotlight: 3 s is shorter than its 5 s minimum; use a longer video.",
+      outputs: [],
+    });
+    expect(await card(started.messageId, started.jobId)).toMatchObject({
+      status: "failed",
+      skipped: [{ platform: "snapchat-spotlight", issues: [{ code: "too_short" }] }],
+    });
+  });
+
  it("refuses appended clips and subtitles the user cannot read", async () => {
    const { runtime, scope, store } = await setup();
    const other = await setup();
--- a/packages/adapters/src/media/video-operations.test.ts
+++ b/packages/adapters/src/media/video-operations.test.ts
@ -1,13 +1,15 @@
 import { rm } from "node:fs/promises";
 import { join } from "node:path";
+import { MEDIA_PLATFORM_PROFILES, MediaPlatformIdSchema } from "@rakazo/contracts";
 import { afterAll, beforeAll, describe, expect, it } from "vitest";
 import { builtinAgentTools } from "../builtin-tools.js";
 import { createMediaOperations } from "../media-operations.js";
 import { MEDIA_CONTINUE_AFTER_PROPERTY } from "../media-tools.js";
 import { parametersFor } from "../pi-runtime.js";
-import { detectFfmpeg, probeMedia, runFfmpeg } from "./ffmpeg.js";
+import { detectFfmpeg, measureLoudness, probeMedia, runFfmpeg } from "./ffmpeg.js";
 import type { TestArtifact, TestClips } from "./media-test-support.js";
 import { createTestClips, fakeMediaJobContext } from "./media-test-support.js";
+import { LOUDNESS_TOLERANCE_LU } from "./platform-export.js";
 import { cleanFileName, createVideoOperations, subtitleFormat } from "./video-operations.js";

 const ffmpeg = await detectFfmpeg();
@ -48,13 +50,22 @@ describe("video operation registrations", () => {
    expect(exported.artifactIds?.(exportInput)).toEqual(["src"]);
  });

-  it("titles exports by aspect ratio unless the bot gave a title", () => {
+  it("titles exports by platform and aspect ratio unless the bot gave a title", () => {
    const exported = operation("export_video");
    expect(
      exported.title(
        exported.inputSchema.parse({ artifact_id: "a", presets: ["vertical", "square"] }),
      ),
    ).toBe("9:16 · 1:1");
+    expect(
+      exported.title(
+        exported.inputSchema.parse({
+          artifact_id: "a",
+          platforms: ["tiktok", "youtube-shorts"],
+          presets: ["square"],
+        }),
+      ),
+    ).toBe("TikTok · YouTube Shorts · 1:1");
    expect(
      exported.title(
        exported.inputSchema.parse({ artifact_id: "a", presets: ["vertical"], title: "Reel" }),
@ -70,6 +81,18 @@ describe("video operation registrations", () => {
      expect(() => parametersFor(tool!)).not.toThrow();
    }
  });
+
+  it("tells the model every platform id with its longest video", () => {
+    const tool = builtinAgentTools.find((entry) => entry.name === "export_video")!;
+    const properties = tool.inputSchema.properties as Record<
+      string,
+      { items?: { enum?: string[] } }
+    >;
+    expect(properties.platforms?.items?.enum).toEqual(MediaPlatformIdSchema.options);
+    for (const profile of Object.values(MEDIA_PLATFORM_PROFILES)) {
+      expect(tool.description).toContain(`${profile.id} ${profile.duration.hardMaxMs / 1000} s`);
+    }
+  });
 });

 describe("subtitle and file name helpers", () => {
@ -251,6 +274,74 @@ describe.skipIf(!ffmpeg)("video operations with ffmpeg", () => {
    expect(progress.at(-1)).toBe(1);
  });

+  it("exports for a platform at its frame, frame rate and loudness, and skips one it is too short for", async () => {
+    const fast = join(clips.dir, "fast.mp4");
+    await runFfmpeg([
+      ...["-f", "lavfi", "-i", "testsrc=size=320x180:rate=60:duration=4"],
+      ...["-f", "lavfi", "-i", "sine=frequency=330:sample_rate=48000:duration=4"],
+      ...["-c:v", "libx264", "-preset", "ultrafast", "-pix_fmt", "yuv420p"],
+      ...["-c:a", "aac", "-shortest", `file:${fast}`],
+    ]);
+    const registration = operation("export_video");
+    const job = await fakeMediaJobContext(
+      registration.inputSchema.parse({
+        artifact_id: "fast",
+        platforms: ["tiktok", "snapchat-spotlight"],
+      }),
+      { fast: { path: fast, name: "Fast clip.mp4", mimeType: "video/mp4" } },
+    );
+    try {
+      const result = await registration.handler.run(job.context);
+      expect(job.skipped).toEqual([
+        {
+          platform: "snapchat-spotlight",
+          issues: [{ code: "too_short", minMs: 5000, actualMs: expect.any(Number) }],
+        },
+      ]);
+      expect(job.outputs).toHaveLength(1);
+      const [output] = job.outputs;
+      expect(output).toMatchObject({
+        name: "Fast clip-tiktok.mp4",
+        platform: "tiktok",
+        width: 1080,
+        height: 1920,
+        parentArtifactId: "fast",
+        check: { status: "pass", issues: [] },
+      });
+      expect(output!.posterSize).toBeGreaterThan(0);
+      const probe = await probeMedia(output!.path, { mimeType: "video/mp4" });
+      expect(probe.video).toMatchObject({ codec: "h264", width: 1080, height: 1920, fps: 30 });
+      expect(Math.abs(probe.durationMs - 4000)).toBeLessThan(100);
+      const loudness = await measureLoudness(
+        output!.path,
+        { integratedLufs: -14, truePeakDb: -1 },
+        { mimeType: "video/mp4" },
+      );
+      expect(Math.abs(loudness.integratedLufs + 14)).toBeLessThanOrEqual(LOUDNESS_TOLERANCE_LU);
+      expect(result.summary).toContain("Fast clip-tiktok.mp4 for TikTok (1080×1920, 4 s)");
+      expect(result.summary).toContain(
+        "Not exported for Snapchat Spotlight: 4 s is shorter than its 5 s minimum; use a longer video.",
+      );
+      expect(job.progress.at(-1)).toBe(1);
+    } finally {
+      await rm(job.tempDir, { recursive: true, force: true });
+    }
+  });
+
+  it("fails without rendering when the video fits none of the platforms", async () => {
+    const registration = operation("export_video");
+    const job = await fakeMediaJobContext(
+      registration.inputSchema.parse({ artifact_id: "land", platforms: ["snapchat-spotlight"] }),
+      artifacts,
+    );
+    await expect(registration.handler.run(job.context)).rejects.toThrow(
+      "Not exported for Snapchat Spotlight: 3 s is shorter than its 5 s minimum; use a longer video.",
+    );
+    expect(job.skipped.map((target) => target.platform)).toEqual(["snapchat-spotlight"]);
+    expect(job.outputs).toEqual([]);
+    await rm(job.tempDir, { recursive: true, force: true });
+  });
+
  it("fails clearly on ranges past the end, non-subtitle files and non-videos", async () => {
    await expect(
      run("edit_video", {
--- a/packages/adapters/src/media/video-operations.ts
+++ b/packages/adapters/src/media/video-operations.ts
@ -1,24 +1,49 @@
-import { copyFile, mkdtemp, open, stat } from "node:fs/promises";
+import { copyFile, mkdtemp, open, rename, stat } from "node:fs/promises";
 import { join } from "node:path";
-import type { MediaJobContext, MediaJobInputFile, MediaOperationResult } from "@rakazo/adapter-kit";
-import type { EditVideoInput, ExportVideoInput, MediaOutput } from "@rakazo/contracts";
+import type {
+  MediaJobContext,
+  MediaJobInputFile,
+  MediaJobOutputFile,
+  MediaOperationResult,
+} from "@rakazo/adapter-kit";
+import type {
+  EditVideoInput,
+  ExportVideoInput,
+  MediaFit,
+  MediaOutput,
+  MediaPlatformId,
+  MediaSkippedTarget,
+  PlatformProfile,
+} from "@rakazo/contracts";
 import {
  ARTIFACT_MAX_BYTES_BY_KIND,
  EditVideoInputSchema,
  ExportVideoInputSchema,
+  MEDIA_PLATFORM_PROFILES,
  MEDIA_PRESETS,
 } from "@rakazo/contracts";
 import type { MediaOperationRegistration } from "../media-runtime.js";
-import type { FfmpegInfo } from "./ffmpeg.js";
+import type { FfmpegInfo, MediaProbe } from "./ffmpeg.js";
 import {
  detectFfmpeg,
+  measureLoudness,
  outputTooLargeMessage,
  probeMedia,
  renderPoster,
  runFfmpeg,
 } from "./ffmpeg.js";
+import type { ExportMeasurement } from "./platform-export.js";
+import {
+  checkExport,
+  describeIssue,
+  describeSkipped,
+  durationIssues,
+  needsLoudnessFix,
+  platformTarget,
+  sizeFixKbps,
+} from "./platform-export.js";
 import type { PlanInput, VideoEditPlan } from "./video-edit-plan.js";
-import { planVideoEdit } from "./video-edit-plan.js";
+import { planLoudnessFix, planVideoEdit } from "./video-edit-plan.js";

 export interface VideoOperationsDeps {
  /** Finds ffmpeg; defaults to PATH lookup. */
@ -66,7 +91,11 @@ export function createVideoOperations(
    operation: "export_video",
    inputSchema: ExportVideoInputSchema,
    title: (input) =>
-      input.title ?? input.presets.map((preset) => MEDIA_PRESETS[preset].aspect).join(" · "),
+      input.title ??
+      [
+        ...(input.platforms ?? []).map((platform) => MEDIA_PLATFORM_PROFILES[platform].name),
+        ...(input.presets ?? []).map((preset) => MEDIA_PRESETS[preset].aspect),
+      ].join(" · "),
    available,
    artifactIds: (input) => [input.artifact_id],
    handler: {
@ -142,39 +171,160 @@ async function runEditVideo(context: MediaJobContext): Promise<MediaOperationRes

 async function runExportVideo(context: MediaJobContext): Promise<MediaOperationResult> {
  const input = ExportVideoInputSchema.parse(context.input);
-  const presets = [...new Set(input.presets)];
+  const platforms = [...new Set(input.platforms ?? [])];
+  const presets = [...new Set(input.presets ?? [])];
  const workDir = await mkdtemp(join(context.tempDir, "export-"));
  const progress = createProgressReporter(context);
  const source = await loadVideo(context, input.artifact_id);
  const base = cleanFileName(withoutExtension(source.name), "video");
+  // A platform the video is too long or too short for is not rendered; the bot trims first.
+  const skipped: MediaSkippedTarget[] = [];
+  const rendered: MediaPlatformId[] = [];
+  for (const platform of platforms) {
+    const issues = durationIssues(MEDIA_PLATFORM_PROFILES[platform], source.probe.durationMs);
+    if (issues.length) skipped.push({ platform, issues });
+    else rendered.push(platform);
+  }
+  for (const target of skipped) await context.addSkipped(target);
+  const notExported = skipped.map(({ platform, issues }) =>
+    describeSkipped(MEDIA_PLATFORM_PROFILES[platform], issues),
+  );
+  const count = rendered.length + presets.length;
+  if (count === 0) throw new Error(notExported.join(" "));
+  const share = 1 / count;
+  const report = (index: number) => progress.range(index * share, (index + 1) * share);
  const outputs: MediaOutput[] = [];
-  for (const [index, preset] of presets.entries()) {
+  for (const platform of rendered) {
+    outputs.push(
+      await exportForPlatform(context, source, MEDIA_PLATFORM_PROFILES[platform], {
+        fit: input.fit,
+        name: `${base}-${platform}.mp4`,
+        workDir,
+        report: report(outputs.length),
+      }),
+    );
+  }
+  for (const preset of presets) {
    const outputPath = join(workDir, `${preset}.mp4`);
    const plan = planVideoEdit({
      source,
      steps: [{ op: "reframe", preset, fit: input.fit }],
      outputPath,
    });
-    const share = 1 / presets.length;
    outputs.push(
-      await encode(
-        context,
-        plan,
-        outputPath,
-        workDir,
-        progress.range(index * share, (index + 1) * share),
-        {
+      await encode(context, plan, outputPath, workDir, report(outputs.length), {
        name: `${base}-${MEDIA_PRESETS[preset].aspect.replace(":", "x")}.mp4`,
        parentArtifactId: source.artifactId,
        preset,
-        },
-      ),
+      }),
    );
  }
  await progress.done();
-  return { summary: `Exported ${source.name} as ${outputs.map(describe).join(", ")}.` };
+  const checks = outputs.flatMap((output) =>
+    output.platform && output.check && output.check.status !== "pass"
+      ? [
+          `${MEDIA_PLATFORM_PROFILES[output.platform].name} check ${output.check.status}: ${output.check.issues.map(describeIssue).join("; ")}.`,
+        ]
+      : [],
+  );
+  return {
+    summary: [
+      `Exported ${source.name} as ${outputs.map(describe).join(", ")}.`,
+      ...checks,
+      ...notExported,
+    ].join(" "),
+  };
 }

+/**
+ * Renders a video to a platform's frame, frame rate, bitrate and loudness, measures the file
+ * and stores it with the check. A file over the size limit is encoded once more at a lower
+ * bitrate, and audio off the loudness target gets one more, linear loudness pass.
+ */
+async function exportForPlatform(
+  context: MediaJobContext,
+  source: PlanInput & MediaJobInputFile,
+  profile: PlatformProfile,
+  options: { fit: MediaFit; name: string; workDir: string; report: (fraction: number) => void },
+): Promise<MediaOutput> {
+  const { workDir, report } = options;
+  const outputPath = join(workDir, `${profile.id}.mp4`);
+  let target = platformTarget(profile, options.fit, source.probe.durationMs);
+  const renderTarget = async () => {
+    const plan = planVideoEdit({ source, steps: [], target, outputPath });
+    await render(context, plan, outputPath, workDir, report);
+    return plan;
+  };
+  let plan = await renderTarget();
+  let measured = await measureExport(context, outputPath, profile);
+  const lowerKbps = sizeFixKbps(profile, measured.result, target.maxBitrateKbps);
+  if (lowerKbps !== null) {
+    target = { ...target, maxBitrateKbps: lowerKbps };
+    plan = await renderTarget();
+    measured = await measureExport(context, outputPath, profile);
+  }
+  if (needsLoudnessFix(profile, measured.result) && measured.result.loudness) {
+    const fixedPath = join(workDir, `${profile.id}-loudness.mp4`);
+    await runFfmpeg(
+      planLoudnessFix({
+        inputPath: outputPath,
+        outputPath: fixedPath,
+        durationMs: measured.result.durationMs,
+        target,
+        measured: measured.result.loudness,
+      }),
+      {
+        signal: context.signal,
+        cwd: workDir,
+        maxOutputBytes: ARTIFACT_MAX_BYTES_BY_KIND.video,
+        outputs: [fixedPath],
+      },
+    );
+    await rename(fixedPath, outputPath);
+    measured = await measureExport(context, outputPath, profile);
+  }
+  return store(context, plan, outputPath, measured.probe, report, {
+    name: options.name,
+    parentArtifactId: source.artifactId,
+    platform: profile.id,
+    check: checkExport(profile, measured.result),
+  });
+}
+
+async function measureExport(
+  context: MediaJobContext,
+  path: string,
+  profile: PlatformProfile,
+): Promise<{ probe: MediaProbe; result: ExportMeasurement }> {
+  const options = { signal: context.signal, mimeType: "video/mp4" };
+  const probe = await probeMedia(path, options);
+  const loudness = probe.hasAudio
+    ? await measureLoudness(
+        path,
+        { integratedLufs: profile.audio.targetLufs, truePeakDb: profile.audio.truePeakDb },
+        options,
+      )
+    : null;
+  return {
+    probe,
+    result: {
+      width: probe.video?.width ?? 0,
+      height: probe.video?.height ?? 0,
+      fps: probe.video?.fps ?? 0,
+      codec: probe.video?.codec ?? "",
+      durationMs: probe.durationMs,
+      sizeBytes: (await stat(path)).size,
+      ...(probe.video?.bitRateKbps !== undefined ? { videoKbps: probe.video.bitRateKbps } : {}),
+      loudness,
+    },
+  };
+}
+
+type OutputDetails = Pick<
+  MediaJobOutputFile,
+  "name" | "parentArtifactId" | "preset" | "platform" | "check"
+>;
+
 /** Runs a plan, checks the result, renders its poster and stores it as an output. */
 async function encode(
  context: MediaJobContext,
@ -182,8 +332,24 @@ async function encode(
  outputPath: string,
  workDir: string,
  report: (fraction: number) => void,
-  file: Pick<Parameters<MediaJobContext["addOutput"]>[0], "name" | "parentArtifactId" | "preset">,
+  file: OutputDetails,
 ): Promise<MediaOutput> {
+  await render(context, plan, outputPath, workDir, report);
+  const probe = await probeMedia(outputPath, {
+    signal: context.signal,
+    mimeType: plan.kind === "audio" ? "audio/mp4" : "video/mp4",
+  });
+  return store(context, plan, outputPath, probe, report, file);
+}
+
+/** Runs a plan's ffmpeg, refusing a result larger than an artifact may be. */
+async function render(
+  context: MediaJobContext,
+  plan: VideoEditPlan,
+  outputPath: string,
+  workDir: string,
+  report: (fraction: number) => void,
+): Promise<void> {
  const maxBytes = ARTIFACT_MAX_BYTES_BY_KIND[plan.kind];
  await runFfmpeg(plan.args, {
    signal: context.signal,
@ -194,10 +360,17 @@ async function encode(
    outputs: [outputPath],
  });
  if ((await stat(outputPath)).size > maxBytes) throw new Error(outputTooLargeMessage(maxBytes));
-  const probe = await probeMedia(outputPath, {
-    signal: context.signal,
-    mimeType: plan.kind === "audio" ? "audio/mp4" : "video/mp4",
-  });
+}
+
+/** Renders a video's poster and stores the file as an output. */
+async function store(
+  context: MediaJobContext,
+  plan: VideoEditPlan,
+  outputPath: string,
+  probe: MediaProbe,
+  report: (fraction: number) => void,
+  file: OutputDetails,
+): Promise<MediaOutput> {
  if (plan.kind === "audio") {
    const output = await context.addOutput({
      ...file,
@ -294,13 +467,16 @@ function withoutExtension(name: string): string {
  return name.replace(/\.[A-Za-z0-9]{1,5}$/, "");
 }

-/** "name (1080×1920, 12.5 s)" for the bot's summary; the runtime adds the artifact ids. */
+/** "name for TikTok (1080×1920, 12.5 s)" for the bot's summary; the runtime adds the ids. */
 function describe(output: MediaOutput): string {
+  const name = output.platform
+    ? `${output.name} for ${MEDIA_PLATFORM_PROFILES[output.platform].name}`
+    : output.name;
  const details = [
    output.width && output.height ? `${output.width}×${output.height}` : "",
    output.durationMs !== undefined ? `${Number((output.durationMs / 1000).toFixed(1))} s` : "",
  ].filter(Boolean);
-  return details.length ? `${output.name} (${details.join(", ")})` : output.name;
+  return details.length ? `${name} (${details.join(", ")})` : name;
 }

 /** Maps ffmpeg progress onto the card: monotonic, written in order, never failing the job. */
--- a/packages/contracts/src/index.ts
+++ b/packages/contracts/src/index.ts
@ -18,6 +18,8 @@ export * from "./media.js";
 export * from "./media-generation.js";
 export * from "./media-jobs.js";
 export * from "./media-library.js";
+export * from "./media-platforms.js";
+export * from "./media-presets.js";
 export * from "./media-settings.js";
 export * from "./media-transcription.js";
 export * from "./media-video.js";
--- a/packages/contracts/src/media-generation.ts
+++ b/packages/contracts/src/media-generation.ts
@ -1,6 +1,6 @@
 import * as z from "zod";
 import { Id } from "./ids.js";
-import { MediaFitSchema, MediaPresetIdSchema } from "./media.js";
+import { MediaFitSchema, MediaPresetIdSchema } from "./media-presets.js";
 import { MediaTitleSchema } from "./media-video.js";

 export const MEDIA_IMAGE_MAX_COUNT = 4;
--- a/packages/contracts/src/media-platforms.test.ts
+++ b/packages/contracts/src/media-platforms.test.ts
@ -0,0 +1,69 @@
+import { describe, expect, it } from "vitest";
+import {
+  MEDIA_PLATFORM_PROFILES,
+  MediaCheckSchema,
+  MediaPlatformIdSchema,
+  PlatformProfileSchema,
+} from "./media-platforms.js";
+import { MEDIA_PRESETS } from "./media-presets.js";
+
+describe("platform profiles", () => {
+  it("ships one valid profile per platform id, keyed by its id", () => {
+    expect(Object.keys(MEDIA_PLATFORM_PROFILES)).toEqual(MediaPlatformIdSchema.options);
+    for (const [id, profile] of Object.entries(MEDIA_PLATFORM_PROFILES)) {
+      expect(PlatformProfileSchema.parse(profile)).toEqual(profile);
+      expect(profile.id).toBe(id);
+      expect(profile.sourceUrls.every((url) => url.startsWith("https://"))).toBe(true);
+    }
+  });
+
+  it("uses only the aspect ratios the presets know, at a size of that ratio", () => {
+    const aspects = new Set<string>(Object.values(MEDIA_PRESETS).map((preset) => preset.aspect));
+    for (const profile of Object.values(MEDIA_PLATFORM_PROFILES)) {
+      expect(aspects.has(profile.video.aspect)).toBe(true);
+    }
+    const tiktok = MEDIA_PLATFORM_PROFILES.tiktok;
+    expect(
+      PlatformProfileSchema.safeParse({ ...tiktok, video: { ...tiktok.video, aspect: "3:2" } })
+        .success,
+    ).toBe(false);
+    expect(
+      PlatformProfileSchema.safeParse({ ...tiktok, video: { ...tiktok.video, width: 1920 } })
+        .success,
+    ).toBe(false);
+    expect(
+      PlatformProfileSchema.safeParse({
+        ...tiktok,
+        duration: { hardMinMs: 5000, hardMaxMs: 4000 },
+      }).success,
+    ).toBe(false);
+  });
+
+  it("keeps the research provenance on every profile", () => {
+    for (const profile of Object.values(MEDIA_PLATFORM_PROFILES)) {
+      expect(profile.reviewedAt).toMatch(/^\d{4}-\d{2}-\d{2}$/);
+      expect(profile.unverified).toBe(true);
+    }
+  });
+});
+
+describe("platform check", () => {
+  it("carries language-neutral issue codes with their numbers", () => {
+    expect(
+      MediaCheckSchema.parse({
+        status: "fail",
+        issues: [
+          { code: "too_long", maxMs: 600_000, actualMs: 720_000 },
+          { code: "codec_mismatch" },
+        ],
+      }).issues,
+    ).toHaveLength(2);
+    expect(
+      MediaCheckSchema.safeParse({ status: "warn", issues: [{ code: "too_blurry" }] }).success,
+    ).toBe(false);
+    expect(
+      MediaCheckSchema.safeParse({ status: "fail", issues: [{ code: "too_long", maxMs: 1 }] })
+        .success,
+    ).toBe(false);
+  });
+});
--- a/packages/contracts/src/media-platforms.ts
+++ b/packages/contracts/src/media-platforms.ts
@ -0,0 +1,282 @@
+import * as z from "zod";
+import type { MediaPreset } from "./media-presets.js";
+import { MEDIA_PRESETS } from "./media-presets.js";
+
+/**
+ * Platforms a video can be exported for. An export renders each one to the platform's
+ * technical limits and checks the file against them, so an upload is not rejected or degraded.
+ */
+export const MediaPlatformIdSchema = z.enum([
+  "tiktok",
+  "instagram-reels",
+  "instagram-feed-4x5",
+  "youtube-shorts",
+  "youtube",
+  "facebook-reels",
+  "linkedin",
+  "x-twitter",
+  "pinterest-video-pin",
+  "snapchat-spotlight",
+]);
+export type MediaPlatformId = z.infer<typeof MediaPlatformIdSchema>;
+
+const PRESET_ASPECTS = Object.values(MEDIA_PRESETS).map((preset) => preset.aspect) as [
+  MediaPreset["aspect"],
+  ...MediaPreset["aspect"][],
+];
+
+const Percent = z.number().min(0).max(50);
+
+/**
+ * The technical limits of a platform. Content, disclosure and caption rules need a review flow
+ * and are not part of a profile.
+ */
+export const PlatformProfileSchema = z
+  .object({
+    id: MediaPlatformIdSchema,
+    /** Brand name, shown untranslated. */
+    name: z.string().min(1).max(40),
+    /** Where the limits come from. */
+    sourceUrls: z.array(z.httpUrl()).min(1),
+    reviewedAt: z.iso.date(),
+    /** True until someone checked the limits against the platform's current documentation. */
+    unverified: z.boolean(),
+    video: z.object({
+      aspect: z.enum(PRESET_ASPECTS),
+      width: z.number().int().positive().multipleOf(2),
+      height: z.number().int().positive().multipleOf(2),
+      /** Highest frame rate; slower sources keep theirs. */
+      fps: z.number().positive().max(120),
+      codec: z.literal("h264"),
+      maxBitrateKbps: z.number().int().positive(),
+      maxFileSizeMb: z.number().positive(),
+    }),
+    duration: z
+      .object({
+        hardMinMs: z.number().int().nonnegative(),
+        hardMaxMs: z.number().int().positive(),
+      })
+      .refine((duration) => duration.hardMinMs < duration.hardMaxMs, "hardMinMs must be lower"),
+    /** Edges the platform covers with its own buttons and captions, in percent of the frame. */
+    safeZones: z.object({
+      topPct: Percent,
+      bottomPct: Percent,
+      leftPct: Percent,
+      rightPct: Percent,
+    }),
+    audio: z.object({
+      targetLufs: z.number().min(-40).max(0),
+      truePeakDb: z.number().min(-10).max(0),
+    }),
+  })
+  .refine((profile) => {
+    const [across, down] = profile.video.aspect.split(":").map(Number);
+    return Math.abs(profile.video.width / profile.video.height - across! / down!) < 0.01;
+  }, "width and height must match the aspect ratio");
+export type PlatformProfile = z.infer<typeof PlatformProfileSchema>;
+
+/**
+ * What a platform check found, with the numbers the UI words it with. Durations in ms, sizes in
+ * MB (10^6 bytes), bitrates in kbps, loudness in LUFS, peaks in dBTP.
+ */
+export const MediaCheckIssueSchema = z.discriminatedUnion("code", [
+  z.object({ code: z.literal("too_long"), maxMs: z.number(), actualMs: z.number() }),
+  z.object({ code: z.literal("too_short"), minMs: z.number(), actualMs: z.number() }),
+  z.object({ code: z.literal("file_too_large"), maxMb: z.number(), actualMb: z.number() }),
+  z.object({ code: z.literal("bitrate_high"), maxKbps: z.number(), actualKbps: z.number() }),
+  z.object({ code: z.literal("loudness_off"), targetLufs: z.number(), actualLufs: z.number() }),
+  z.object({ code: z.literal("true_peak_high"), maxDb: z.number(), actualDb: z.number() }),
+  z.object({
+    code: z.literal("resolution_mismatch"),
+    width: z.number(),
+    height: z.number(),
+    actualWidth: z.number(),
+    actualHeight: z.number(),
+  }),
+  z.object({ code: z.literal("fps_mismatch"), maxFps: z.number(), actualFps: z.number() }),
+  z.object({ code: z.literal("codec_mismatch") }),
+]);
+export type MediaCheckIssue = z.infer<typeof MediaCheckIssueSchema>;
+
+/** `fail`: the platform would reject the file. `warn`: it would accept and degrade it. */
+export const MediaCheckSchema = z.object({
+  status: z.enum(["pass", "warn", "fail"]),
+  /** Most severe first. */
+  issues: z.array(MediaCheckIssueSchema).max(20),
+});
+export type MediaCheck = z.infer<typeof MediaCheckSchema>;
+
+/** A platform an export did not render, e.g. because the video is too long for it. */
+export const MediaSkippedTargetSchema = z.object({
+  platform: MediaPlatformIdSchema,
+  issues: z.array(MediaCheckIssueSchema).min(1).max(20),
+});
+export type MediaSkippedTarget = z.infer<typeof MediaSkippedTargetSchema>;
+
+const VERTICAL_SAFE_ZONES = { topPct: 10, bottomPct: 20, leftPct: 5, rightPct: 15 };
+const FRAMED_SAFE_ZONES = { topPct: 5, bottomPct: 10, leftPct: 5, rightPct: 5 };
+const STREAMING_LOUDNESS = { targetLufs: -14, truePeakDb: -1 };
+const VERTICAL_1080 = { aspect: "9:16", width: 1080, height: 1920 } as const;
+const REVIEWED_AT = "2026-10-03";
+
+/**
+ * Researched limits, all unverified: each needs a check against the linked documentation before
+ * it is trusted. YouTube allows 60 fps per its encoding guide; the others are capped at 30.
+ */
+export const MEDIA_PLATFORM_PROFILES: Readonly<Record<MediaPlatformId, PlatformProfile>> = {
+  tiktok: {
+    id: "tiktok",
+    name: "TikTok",
+    sourceUrls: ["https://support.tiktok.com/en/using-tiktok/creating-videos/upload-videos"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: { ...VERTICAL_1080, fps: 30, codec: "h264", maxBitrateKbps: 8000, maxFileSizeMb: 287 },
+    duration: { hardMinMs: 3000, hardMaxMs: 600_000 },
+    safeZones: VERTICAL_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  "instagram-reels": {
+    id: "instagram-reels",
+    name: "Instagram Reels",
+    sourceUrls: ["https://help.instagram.com/", "https://www.facebook.com/business/ads-guide/"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: { ...VERTICAL_1080, fps: 30, codec: "h264", maxBitrateKbps: 5000, maxFileSizeMb: 1024 },
+    duration: { hardMinMs: 3000, hardMaxMs: 90_000 },
+    safeZones: VERTICAL_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  "instagram-feed-4x5": {
+    id: "instagram-feed-4x5",
+    name: "Instagram Feed",
+    sourceUrls: ["https://help.instagram.com/", "https://www.facebook.com/business/ads-guide/"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: {
+      aspect: "4:5",
+      width: 1080,
+      height: 1350,
+      fps: 30,
+      codec: "h264",
+      maxBitrateKbps: 5000,
+      maxFileSizeMb: 1024,
+    },
+    duration: { hardMinMs: 3000, hardMaxMs: 60_000 },
+    safeZones: FRAMED_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  "youtube-shorts": {
+    id: "youtube-shorts",
+    name: "YouTube Shorts",
+    sourceUrls: [
+      "https://support.google.com/youtube/answer/15424877",
+      "https://support.google.com/youtube/answer/10059070",
+      "https://support.google.com/youtube/answer/1722171",
+    ],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: {
+      ...VERTICAL_1080,
+      fps: 60,
+      codec: "h264",
+      maxBitrateKbps: 12_000,
+      maxFileSizeMb: 2048,
+    },
+    duration: { hardMinMs: 1000, hardMaxMs: 180_000 },
+    safeZones: VERTICAL_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  youtube: {
+    id: "youtube",
+    name: "YouTube",
+    sourceUrls: [
+      "https://support.google.com/youtube/answer/1722171",
+      "https://support.google.com/youtube/answer/71673",
+    ],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: {
+      aspect: "16:9",
+      width: 1920,
+      height: 1080,
+      fps: 60,
+      codec: "h264",
+      maxBitrateKbps: 8000,
+      maxFileSizeMb: 4096,
+    },
+    duration: { hardMinMs: 1000, hardMaxMs: 900_000 },
+    safeZones: FRAMED_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  "facebook-reels": {
+    id: "facebook-reels",
+    name: "Facebook Reels",
+    sourceUrls: ["https://www.facebook.com/help/", "https://www.facebook.com/business/ads-guide/"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: { ...VERTICAL_1080, fps: 30, codec: "h264", maxBitrateKbps: 5000, maxFileSizeMb: 1024 },
+    duration: { hardMinMs: 3000, hardMaxMs: 90_000 },
+    safeZones: VERTICAL_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  linkedin: {
+    id: "linkedin",
+    name: "LinkedIn",
+    sourceUrls: ["https://www.linkedin.com/help/linkedin/"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: {
+      aspect: "16:9",
+      width: 1920,
+      height: 1080,
+      fps: 30,
+      codec: "h264",
+      maxBitrateKbps: 8000,
+      maxFileSizeMb: 5000,
+    },
+    duration: { hardMinMs: 3000, hardMaxMs: 600_000 },
+    safeZones: FRAMED_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  "x-twitter": {
+    id: "x-twitter",
+    name: "X",
+    sourceUrls: ["https://help.x.com/en/using-x/x-videos"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: {
+      aspect: "16:9",
+      width: 1280,
+      height: 720,
+      fps: 30,
+      codec: "h264",
+      maxBitrateKbps: 5000,
+      maxFileSizeMb: 512,
+    },
+    duration: { hardMinMs: 1000, hardMaxMs: 140_000 },
+    safeZones: FRAMED_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  "pinterest-video-pin": {
+    id: "pinterest-video-pin",
+    name: "Pinterest",
+    sourceUrls: ["https://help.pinterest.com/en/business"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: { ...VERTICAL_1080, fps: 30, codec: "h264", maxBitrateKbps: 8000, maxFileSizeMb: 2048 },
+    duration: { hardMinMs: 4000, hardMaxMs: 300_000 },
+    safeZones: VERTICAL_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+  "snapchat-spotlight": {
+    id: "snapchat-spotlight",
+    name: "Snapchat Spotlight",
+    sourceUrls: ["https://help.snapchat.com/hc/en-us"],
+    reviewedAt: REVIEWED_AT,
+    unverified: true,
+    video: { ...VERTICAL_1080, fps: 30, codec: "h264", maxBitrateKbps: 5000, maxFileSizeMb: 250 },
+    duration: { hardMinMs: 5000, hardMaxMs: 60_000 },
+    safeZones: VERTICAL_SAFE_ZONES,
+    audio: STREAMING_LOUDNESS,
+  },
+};
--- a/packages/contracts/src/media-presets.ts
+++ b/packages/contracts/src/media-presets.ts
@ -0,0 +1,28 @@
+import * as z from "zod";
+
+/**
+ * Output formats for video cuts and exports. Width and height are the encoded frame; every
+ * preset encodes H.264 + AAC in MP4 so the result plays everywhere it is posted.
+ */
+export const MEDIA_PRESETS = {
+  vertical: { aspect: "9:16", width: 1080, height: 1920 },
+  landscape: { aspect: "16:9", width: 1920, height: 1080 },
+  square: { aspect: "1:1", width: 1080, height: 1080 },
+  portrait: { aspect: "4:5", width: 1080, height: 1350 },
+  classic: { aspect: "4:3", width: 1440, height: 1080 },
+  cinema: { aspect: "21:9", width: 2560, height: 1080 },
+} as const;
+export const MediaPresetIdSchema = z.enum([
+  "vertical",
+  "landscape",
+  "square",
+  "portrait",
+  "classic",
+  "cinema",
+]);
+export type MediaPresetId = z.infer<typeof MediaPresetIdSchema>;
+export type MediaPreset = (typeof MEDIA_PRESETS)[MediaPresetId];
+
+/** How a frame of another aspect ratio fills a preset. */
+export const MediaFitSchema = z.enum(["crop", "pad", "blur"]);
+export type MediaFit = z.infer<typeof MediaFitSchema>;
--- a/packages/contracts/src/media-video.test.ts
+++ b/packages/contracts/src/media-video.test.ts
@ -42,15 +42,42 @@ describe("edit_video input", () => {
 });

 describe("export_video input", () => {
-  it("needs at least one preset and defaults to cropping", () => {
+  it("needs at least one preset or platform and defaults to cropping", () => {
    expect(ExportVideoInputSchema.parse({ artifact_id: "a", presets: ["square"] })).toEqual({
      artifact_id: "a",
      presets: ["square"],
      fit: "crop",
    });
+    expect(ExportVideoInputSchema.parse({ artifact_id: "a", platforms: ["tiktok"] })).toEqual({
+      artifact_id: "a",
+      platforms: ["tiktok"],
+      fit: "crop",
+    });
    expect(ExportVideoInputSchema.safeParse({ artifact_id: "a", presets: [] }).success).toBe(false);
+    expect(ExportVideoInputSchema.safeParse({ artifact_id: "a" }).success).toBe(false);
    expect(ExportVideoInputSchema.safeParse({ artifact_id: "a", presets: ["imax"] }).success).toBe(
      false,
    );
+    expect(
+      ExportVideoInputSchema.safeParse({ artifact_id: "a", platforms: ["myspace"] }).success,
+    ).toBe(false);
+  });
+
+  it("takes at most six targets across platforms and presets", () => {
+    const platforms = ["tiktok", "youtube-shorts", "instagram-reels", "linkedin"];
+    expect(
+      ExportVideoInputSchema.safeParse({
+        artifact_id: "a",
+        platforms,
+        presets: ["square", "portrait"],
+      }).success,
+    ).toBe(true);
+    const tooMany = ExportVideoInputSchema.safeParse({
+      artifact_id: "a",
+      platforms,
+      presets: ["square", "portrait", "classic"],
+    });
+    expect(tooMany.success).toBe(false);
+    expect(tooMany.error?.issues[0]?.path).toEqual(["platforms"]);
  });
 });
--- a/packages/contracts/src/media-video.ts
+++ b/packages/contracts/src/media-video.ts
@ -1,6 +1,7 @@
 import * as z from "zod";
 import { Id } from "./ids.js";
-import { MediaFitSchema, MediaPresetIdSchema } from "./media.js";
+import { MediaPlatformIdSchema } from "./media-platforms.js";
+import { MediaFitSchema, MediaPresetIdSchema } from "./media-presets.js";

 /**
 * Inputs of the `edit_video` and `export_video` media operations, which are also the arguments
@ -71,10 +72,25 @@ export const EditVideoInputSchema = z
  });
 export type EditVideoInput = z.infer<typeof EditVideoInputSchema>;

-export const ExportVideoInputSchema = z.object({
+export const MAX_EXPORT_TARGETS = 6;
+
+/** One output per platform and per preset: at least one, at most MAX_EXPORT_TARGETS in all. */
+export const ExportVideoInputSchema = z
+  .object({
    artifact_id: Id,
-  presets: z.array(MediaPresetIdSchema).min(1).max(6),
+    platforms: z.array(MediaPlatformIdSchema).max(MAX_EXPORT_TARGETS).optional(),
+    presets: z.array(MediaPresetIdSchema).max(MAX_EXPORT_TARGETS).optional(),
    fit: MediaFitSchema.default("crop"),
    title: MediaTitleSchema.optional(),
-});
+  })
+  .refine(
+    (input) => {
+      const targets = (input.platforms?.length ?? 0) + (input.presets?.length ?? 0);
+      return targets >= 1 && targets <= MAX_EXPORT_TARGETS;
+    },
+    {
+      path: ["platforms"],
+      message: `name 1 to ${MAX_EXPORT_TARGETS} platforms and presets in all`,
+    },
+  );
 export type ExportVideoInput = z.infer<typeof ExportVideoInputSchema>;
--- a/packages/contracts/src/media.ts
+++ b/packages/contracts/src/media.ts
@ -1,5 +1,11 @@
 import * as z from "zod";
 import { Id } from "./ids.js";
+import {
+  MediaCheckSchema,
+  MediaPlatformIdSchema,
+  MediaSkippedTargetSchema,
+} from "./media-platforms.js";
+import { MediaPresetIdSchema } from "./media-presets.js";

 /** What a media job does. Generation runs on the configured image/video backend, edits run locally. */
 export const MediaOperationSchema = z.enum([
@ -32,33 +38,6 @@ export const MEDIA_JOB_ACTIVE_STATUSES = [
 export const MediaOutputKindSchema = z.enum(["image", "video", "audio", "file"]);
 export type MediaOutputKind = z.infer<typeof MediaOutputKindSchema>;

-/**
- * Output formats for video cuts and exports. Width and height are the encoded frame; every
- * preset encodes H.264 + AAC in MP4 so the result plays everywhere it is posted.
- */
-export const MEDIA_PRESETS = {
-  vertical: { aspect: "9:16", width: 1080, height: 1920 },
-  landscape: { aspect: "16:9", width: 1920, height: 1080 },
-  square: { aspect: "1:1", width: 1080, height: 1080 },
-  portrait: { aspect: "4:5", width: 1080, height: 1350 },
-  classic: { aspect: "4:3", width: 1440, height: 1080 },
-  cinema: { aspect: "21:9", width: 2560, height: 1080 },
-} as const;
-export const MediaPresetIdSchema = z.enum([
-  "vertical",
-  "landscape",
-  "square",
-  "portrait",
-  "classic",
-  "cinema",
-]);
-export type MediaPresetId = z.infer<typeof MediaPresetIdSchema>;
-export type MediaPreset = (typeof MEDIA_PRESETS)[MediaPresetId];
-
-/** How a frame of another aspect ratio fills a preset. */
-export const MediaFitSchema = z.enum(["crop", "pad", "blur"]);
-export type MediaFit = z.infer<typeof MediaFitSchema>;
-
 export const MediaOutputSchema = z.object({
  artifactId: Id,
  kind: MediaOutputKindSchema,
@ -72,6 +51,9 @@ export const MediaOutputSchema = z.object({
  /** The artifact this output was made from, for version history. */
  parentArtifactId: Id.optional(),
  preset: MediaPresetIdSchema.optional(),
+  /** The platform it was exported for, and how it measured against that platform's limits. */
+  platform: MediaPlatformIdSchema.optional(),
+  check: MediaCheckSchema.optional(),
 });
 export type MediaOutput = z.infer<typeof MediaOutputSchema>;

@ -86,6 +68,8 @@ export const MediaJobBlockSchema = z.object({
  progress: z.number().min(0).max(1).optional(),
  error: z.string().optional(),
  outputs: z.array(MediaOutputSchema),
+  /** Platforms an export did not render, each with the reason. */
+  skipped: z.array(MediaSkippedTargetSchema).optional(),
 });
 export type MediaJobBlock = z.infer<typeof MediaJobBlockSchema>;