fix: bound invalid render durations

docs/guides/claude-design-hyperframes.md

@@ -374,7 +374,7 @@ The skeleton handles most structural rules. These are the runtime rules the skel
 | `Math.random()`                   | Seeded PRNG (only if you need randomness)      |
 | `Date.now()`, `performance.now()` | Hard-coded timing or `tl.time()` in `onUpdate` |
 | `setInterval`, `setTimeout`       | Timeline tweens + `onUpdate`                   |
-| `repeat: -1`                      | `repeat: Math.ceil(duration / cycle) - 1`      |
+| `repeat: -1`                      | `repeat: Math.max(0, Math.floor(duration / cycle) - 1)` |
 | `stagger: { from: "random" }`     | `from: "start"`, `"center"`, `"end"`           |
 | Async timeline construction       | Synchronous at page load                       |
 

docs/guides/claude-design-send-to-hyperframes.md

@@ -371,7 +371,7 @@ The cloud renderer seeks the timeline frame-by-frame. Non-deterministic or self-
 | `Date.now()`, `performance.now()` | hard-coded timing or `tl.time()` in `onUpdate` |
 | `setInterval`, `setTimeout` | timeline tweens + `onUpdate` |
 | `requestAnimationFrame` | GSAP tweens |
-| `repeat: -1` | `repeat: Math.ceil(duration / cycle) - 1` |
+| `repeat: -1` | `repeat: Math.max(0, Math.floor(duration / cycle) - 1)` |
 | `stagger: { from: "random" }` | `from: "start"`, `"center"`, or `"end"` |
 | async timeline construction | build synchronously at page load |
 | `video.play()` / `audio.play()` | the framework owns playback |

packages/engine/src/services/frameCapture-staticDedupTimelineCall.test.ts

@@ -1,5 +1,9 @@
 import { describe, it, expect, vi } from "vitest";
-import { computeStaticFrameSet } from "./frameCapture.js";
+import {
+  computeStaticFrameSet,
+  isStaticDedupFrameAnalysisSafe,
+  MAX_STATIC_DEDUP_ANALYSIS_FRAMES,
+} from "./frameCapture.js";
 
 /**
  * Regression lock: a GSAP `tl.call()` disqualifies a composition from
@@ -65,4 +69,40 @@ describe("computeStaticFrameSet disqualifies a comp containing a tl.call()", ()
     expect(result.eligible).toBe(true);
     expect(result.staticFrameSet.size).toBeGreaterThan(0);
   });
+
+  it("fails closed before allocating frame Sets for a sentinel-sized duration", async () => {
+    const page = {
+      evaluate: vi.fn().mockResolvedValueOnce({
+        intervals: [{ start: 0, end: 10_000_000_000 }],
+        tweenCount: 1,
+        duration: 10_000_000_000,
+        hasVideo: false,
+        hasCanvas: false,
+        hasNonGsapAnim: false,
+        hasUnresolvableClipStart: false,
+        hasTimelineCall: false,
+      }),
+    } as unknown as Parameters<typeof computeStaticFrameSet>[0];
+
+    const result = await computeStaticFrameSet(page, 30);
+
+    expect(result.eligible).toBe(false);
+    expect(result.reason).toContain("frame analysis limit");
+    expect(result.staticFrameSet.size).toBe(0);
+    // No clip-boundary scan: oversized metadata exits before frame-index work starts.
+    expect(page.evaluate).toHaveBeenCalledTimes(1);
+  });
+});
+
+describe("static-dedup frame analysis cardinality", () => {
+  it("accepts the configured boundary and rejects the next frame", () => {
+    expect(isStaticDedupFrameAnalysisSafe(MAX_STATIC_DEDUP_ANALYSIS_FRAMES)).toBe(true);
+    expect(isStaticDedupFrameAnalysisSafe(MAX_STATIC_DEDUP_ANALYSIS_FRAMES + 1)).toBe(false);
+  });
+
+  it("rejects non-finite, unsafe, and non-positive frame counts", () => {
+    expect(isStaticDedupFrameAnalysisSafe(Number.POSITIVE_INFINITY)).toBe(false);
+    expect(isStaticDedupFrameAnalysisSafe(Number.MAX_SAFE_INTEGER + 1)).toBe(false);
+    expect(isStaticDedupFrameAnalysisSafe(0)).toBe(false);
+  });
 });

packages/engine/src/services/frameCapture.ts

@@ -2376,6 +2376,20 @@ async function computeClipBoundaryFrames(page: Page, fps: number): Promise<Set<n
   return frames;
 }
 
+// Static dedup is an optional optimization. Building frame-index Sets scales with the
+// composition's declared duration, so malformed/sentinel durations must fail closed before
+// allocating them. Normal capture and the producer's typed duration validation still proceed.
+export const MAX_STATIC_DEDUP_ANALYSIS_FRAMES = 1_000_000;
+
+export function isStaticDedupFrameAnalysisSafe(totalFrames: number): boolean {
+  return (
+    Number.isFinite(totalFrames) &&
+    Number.isSafeInteger(totalFrames) &&
+    totalFrames > 0 &&
+    totalFrames <= MAX_STATIC_DEDUP_ANALYSIS_FRAMES
+  );
+}
+
 /**
  * Predict the dedupable (static) frame set from window.__timelines. A frame f (f>0) is
  * static iff NEITHER f NOR f-1 falls inside any GSAP tween interval — content didn't
@@ -2518,6 +2532,18 @@ export async function computeStaticFrameSet(
     hasTimelineCall: boolean;
   };
   const totalFrames = Math.max(1, Math.ceil(duration * fps));
+  if (!isStaticDedupFrameAnalysisSafe(totalFrames)) {
+    return {
+      totalFrames,
+      staticFrameSet: new Set<number>(),
+      hasVideo,
+      hasCanvas,
+      hasNonGsapAnim,
+      tweenCount,
+      eligible: false,
+      reason: `static-dedup frame analysis limit (${MAX_STATIC_DEDUP_ANALYSIS_FRAMES})`,
+    };
+  }
   const animated = new Set<number>();
   for (const { start, end } of intervals) {
     const lo = Math.max(0, Math.floor(start * fps));

packages/lint/src/rules/gsap.test.ts

@@ -862,6 +862,7 @@ describe("GSAP rules", () => {
     expect(finding).toBeDefined();
     expect(finding?.severity).toBe("error");
     expect(finding?.message).toContain("repeat: -1");
+    expect(finding?.fixHint).toContain("Math.max(0, Math.floor");
   });
 
   it("does not error on finite repeat values", async () => {
@@ -881,6 +882,44 @@ describe("GSAP rules", () => {
     expect(finding).toBeUndefined();
   });
 
+  it("warns when a computed finite repeat can fall through to GSAP's -1 sentinel", async () => {
+    const html = `
+<html><body>
+  <div data-composition-id="main" data-width="1920" data-height="1080"></div>
+  <script src="https://cdn.jsdelivr.net/npm/gsap@3/dist/gsap.min.js"></script>
+  <script>
+    const duration = 0.5;
+    const cycleDuration = 1;
+    const tl = gsap.timeline({ paused: true, repeat: Math.floor(duration / cycleDuration) - 1 });
+    window.__timelines = { main: tl };
+  </script>
+</body></html>`;
+    const result = await lintHyperframeHtml(html);
+    const finding = result.findings.find((f) => f.code === "gsap_repeat_floor_unclamped");
+    expect(finding?.severity).toBe("warning");
+    expect(finding?.fixHint).toContain("Math.max(0, Math.floor");
+  });
+
+  it("accepts a clamped computed finite repeat", async () => {
+    const html = `
+<html><body>
+  <div data-composition-id="main" data-width="1920" data-height="1080"></div>
+  <script src="https://cdn.jsdelivr.net/npm/gsap@3/dist/gsap.min.js"></script>
+  <script>
+    const duration = 0.5;
+    const cycleDuration = 1;
+    const tl = gsap.timeline({
+      paused: true,
+      repeat: Math.max(0, Math.floor(duration / cycleDuration) - 1),
+    });
+    window.__timelines = { main: tl };
+  </script>
+</body></html>`;
+    const result = await lintHyperframeHtml(html);
+    const finding = result.findings.find((f) => f.code === "gsap_repeat_floor_unclamped");
+    expect(finding).toBeUndefined();
+  });
+
   it("does not error on repeat: -1 inside JavaScript comments", async () => {
     const html = `
 <html><body>

packages/lint/src/rules/gsap.ts

@@ -1481,10 +1481,10 @@ export const gsapRules: LintRule<LintContext>[] = [
         message:
           "GSAP tween uses `repeat: -1` (infinite). Infinite repeats break the deterministic " +
           "capture engine which seeks to exact frame times. Use a finite repeat count calculated " +
-          "from the composition duration: `repeat: Math.floor(duration / cycleDuration) - 1`.",
+          "from the composition duration: `repeat: Math.max(0, Math.floor(duration / cycleDuration) - 1)`.",
         fixHint:
-          "Replace `repeat: -1` with a finite count, e.g. `repeat: Math.floor(totalDuration / singleCycleDuration) - 1`. " +
-          "Use Math.floor (not Math.ceil) to ensure the animation fits within the total duration.",
+          "Replace `repeat: -1` with a finite count, e.g. `repeat: Math.max(0, Math.floor(totalDuration / singleCycleDuration) - 1)`. " +
+          "Use Math.floor (not Math.ceil) so the animation fits, and clamp at zero so a short composition cannot evaluate to -1.",
         snippet: truncateSnippet(snippet),
       });
     }
@@ -1510,7 +1510,7 @@ export const gsapRules: LintRule<LintContext>[] = [
           "For example, Math.ceil(10.5 / 2) - 1 = 5 repeats → 6 cycles × 2s = 12s, exceeding 10.5s.",
         fixHint:
           "Use `Math.floor` instead of `Math.ceil` to ensure the animation fits within the duration: " +
-          "`repeat: Math.floor(totalDuration / cycleDuration) - 1`. " +
+          "`repeat: Math.max(0, Math.floor(totalDuration / cycleDuration) - 1)`. " +
           "Math.floor(10.5 / 2) - 1 = 4 repeats → 5 cycles × 2s = 10s ✓",
         snippet: truncateSnippet(snippet),
       });
@@ -1518,6 +1518,33 @@ export const gsapRules: LintRule<LintContext>[] = [
     return findings;
   },
 
+  // gsap_repeat_floor_unclamped
+  ({ scripts }) => {
+    const findings: HyperframeLintFinding[] = [];
+    // A direct floor-minus-one expression becomes GSAP's infinite -1 sentinel when
+    // the visible duration is shorter than one full cycle. Math.max-wrapped forms
+    // intentionally do not match because `repeat:` is followed by Math.max, not Math.floor.
+    const pattern = /repeat\s*:\s*Math\.floor\s*\([^)]+\)\s*-\s*1/g;
+    for (const { snippet } of scanScriptsForRegexMatches(scripts, pattern, {
+      stripComments: false,
+      contextBefore: 40,
+      contextAfter: 40,
+    })) {
+      findings.push({
+        code: "gsap_repeat_floor_unclamped",
+        severity: "warning",
+        message:
+          "GSAP repeat calculation can evaluate to -1 when the composition is shorter than one cycle, " +
+          "which GSAP interprets as an infinite repeat.",
+        fixHint:
+          "Clamp the finite repeat count at zero: " +
+          "`repeat: Math.max(0, Math.floor(totalDuration / cycleDuration) - 1)`.",
+        snippet: truncateSnippet(snippet),
+      });
+    }
+    return findings;
+  },
+
   // scene_layer_missing_visibility_kill
   ({ scripts, tags }) => {
     const findings: HyperframeLintFinding[] = [];

packages/producer/src/services/render/planValidation.test.ts

@@ -11,10 +11,13 @@ import {
   BROWSER_GPU_NOT_SOFTWARE,
   DISTRIBUTED_DURATION_OUT_OF_RANGE,
   MAX_DISTRIBUTED_DURATION_SECONDS,
+  MAX_RENDER_DURATION_SECONDS,
   PlanValidationError,
+  RENDER_DURATION_OUT_OF_RANGE,
   SYSTEM_FONT_USED,
   parseFontFamilyValue,
   validateDistributedDuration,
+  validateRenderDuration,
   validateNoGpuEncode,
   validateNoSystemFonts,
 } from "./planValidation.js";
@@ -95,6 +98,18 @@ describe("validateNoGpuEncode", () => {
 });
 
 describe("validateDistributedDuration", () => {
+  it("keeps the generic validator and legacy distributed API behavior aligned", () => {
+    expect(MAX_RENDER_DURATION_SECONDS).toBe(MAX_DISTRIBUTED_DURATION_SECONDS);
+    expect(RENDER_DURATION_OUT_OF_RANGE).toBe(DISTRIBUTED_DURATION_OUT_OF_RANGE);
+    expect(() =>
+      validateRenderDuration({
+        duration: MAX_RENDER_DURATION_SECONDS,
+        totalFrames: MAX_RENDER_DURATION_SECONDS * 30,
+        fps: 30,
+      }),
+    ).not.toThrow();
+  });
+
   it("accepts a finite duration within the distributed ceiling", () => {
     expect(() =>
       validateDistributedDuration({

packages/producer/src/services/render/planValidation.ts

@@ -67,17 +67,15 @@ export interface ValidateNoGpuEncodeInput {
  */
 export const SYSTEM_FONT_USED = "SYSTEM_FONT_USED";
 
-/**
- * Typed code for {@link validateDistributedDuration}. A duration this large
- * almost always means an unbounded runtime timeline escaped into plan(),
- * e.g. GSAP `repeat: -1` reporting its internal sentinel duration. Letting
- * that reach chunk planning creates billions of frames and turns an authoring
- * error into worker churn.
- */
+/** Typed code for invalid duration metadata resolved by the shared browser probe. */
 export const DISTRIBUTED_DURATION_OUT_OF_RANGE = "DISTRIBUTED_DURATION_OUT_OF_RANGE";
+/** Generic alias; the legacy value remains stable for workflow retry policies. */
+export const RENDER_DURATION_OUT_OF_RANGE = DISTRIBUTED_DURATION_OUT_OF_RANGE;
 
-/** Distributed renders are operationally bounded to one day of output. */
+/** All render paths are operationally bounded to one day of output. */
 export const MAX_DISTRIBUTED_DURATION_SECONDS = 24 * 60 * 60;
+/** Generic alias retained alongside the distributed public API. */
+export const MAX_RENDER_DURATION_SECONDS = MAX_DISTRIBUTED_DURATION_SECONDS;
 
 /**
  * Reject any config that would let GPU encode or hardware-GL slip into a
@@ -143,13 +141,13 @@ export function validateNoSystemFonts(compiledHtml: string): void {
   }
 }
 
-export function validateDistributedDuration(input: {
+export function validateRenderDuration(input: {
   duration: number;
   totalFrames: number;
   fps: number;
 }): void {
   const { duration, totalFrames, fps } = input;
-  const maxFrames = Math.ceil(MAX_DISTRIBUTED_DURATION_SECONDS * fps);
+  const maxFrames = Math.ceil(MAX_RENDER_DURATION_SECONDS * fps);
   if (
     Number.isFinite(duration) &&
     duration > 0 &&
@@ -163,12 +161,21 @@ export function validateDistributedDuration(input: {
   }
 
   throw new PlanValidationError(
-    DISTRIBUTED_DURATION_OUT_OF_RANGE,
-    `[planValidation] Distributed render duration is out of range: ` +
+    RENDER_DURATION_OUT_OF_RANGE,
+    `[planValidation] Render duration is out of range: ` +
       `duration=${String(duration)}s totalFrames=${String(totalFrames)} fps=${String(fps)} ` +
-      `(maxDuration=${String(MAX_DISTRIBUTED_DURATION_SECONDS)}s, maxFrames=${String(maxFrames)}). ` +
+      `(maxDuration=${String(MAX_RENDER_DURATION_SECONDS)}s, maxFrames=${String(maxFrames)}). ` +
       `This usually means an unbounded timeline escaped into render planning, such as ` +
       `GSAP repeat:-1 / yoyo loops without an explicit finite root duration. Add a finite ` +
       `data-duration or replace infinite repeats with a finite repeat count before rendering.`,
   );
 }
+
+/** Backward-compatible distributed entry point for existing adopters. */
+export function validateDistributedDuration(input: {
+  duration: number;
+  totalFrames: number;
+  fps: number;
+}): void {
+  validateRenderDuration(input);
+}

packages/producer/src/services/renderOrchestrator.ts

@@ -147,6 +147,7 @@ import {
 } from "./render/videoFrameCoverage.js";
 import { runCompileStage } from "./render/stages/compileStage.js";
 import { runProbeStage } from "./render/stages/probeStage.js";
+import { validateRenderDuration } from "./render/planValidation.js";
 import {
   runExtractVideosStage,
   shouldCopyExtractedFrames,
@@ -1971,6 +1972,11 @@ async function executeRenderPipeline(input: {
     job.totalFrames = probeResult.totalFrames;
     const totalFrames = probeResult.totalFrames;
     captureTotalFrames = totalFrames;
+    validateRenderDuration({
+      duration: probeResult.duration,
+      totalFrames,
+      fps: fpsToNumber(job.config.fps),
+    });
 
     perfStages.browserProbeMs = probeResult.browserProbeMs;
     perfStages.compileMs = Date.now() - stage1Start;

skills-manifest.json

@@ -66,7 +66,7 @@
       "files": 26
     },
     "remotion-to-hyperframes": {
-      "hash": "c96bb2f0af9e1143",
+      "hash": "3a0e6c2affb9f74e",
       "files": 70
     },
     "slideshow": {

skills/remotion-to-hyperframes/references/api-map.md

@@ -31,7 +31,7 @@ See [sequencing.md](sequencing.md) for nesting and stagger details.
 | ------------------------------------------ | --------------------------------------------------------------------------------------------------------- |
 | `<Sequence from={F} durationInFrames={D}>` | `<div data-start="<F/fps>" data-duration="<D/fps>" data-track-index="N">`                                 |
 | `<Series>` + `<Series.Sequence>`           | siblings with sequential `data-start` values                                                              |
-| `<Loop durationInFrames={D}>`              | not a primitive — emit a custom GSAP `repeat: -1` loop with manual offset math                            |
+| `<Loop durationInFrames={D}>`              | not a primitive — emit a bounded GSAP repeat from the available duration                                  |
 | `<Freeze frame={F}>`                       | drop the wrapper; HF doesn't have running animation outside the seek-driven timeline so freeze is a no-op |
 
 ## Timing

skills/remotion-to-hyperframes/references/limitations.md

@@ -44,10 +44,10 @@ output but visually-identical video, so SSIM passes — just flag it.
 </Loop>
 ```
 
-Loop with `repeat: -1` works for _visual_ repetition. If the looped
-child has cross-iteration state (a counter, a randomness seed), HF
-won't reproduce it identically per iteration. Bow out unless the
-child is fully deterministic per-iteration.
+A bounded GSAP repeat can reproduce _visual_ repetition when its finite count is derived
+from the visible duration. If the looped child has cross-iteration state (a counter, a
+randomness seed), HF won't reproduce it identically per iteration. Bow out unless the child
+is fully deterministic per-iteration; never use `repeat: -1`.
 
 ### Remotion's `<Img>` with crossOrigin
 

skills/remotion-to-hyperframes/references/sequencing.md

@@ -153,11 +153,14 @@ For Remotion `<TransitionSeries>` translations see [transitions.md](transitions.
 </Loop>
 ```
 
-HF doesn't have a `<Loop>` primitive. Translate to a GSAP timeline with
-`repeat: -1`:
+HF doesn't have a `<Loop>` primitive. Translate it to a bounded GSAP timeline using
+the time available at its insertion point:
 
 ```js
-const spinTl = gsap.timeline({ paused: true, repeat: -1, repeatRefresh: false });
+const cycleDuration = 1;
+const availableDuration = compositionDuration - 3;
+const repeat = Math.max(0, Math.floor(availableDuration / cycleDuration) - 1);
+const spinTl = gsap.timeline({ paused: true, repeat, repeatRefresh: false });
 spinTl.to(spinner, { rotate: 360, duration: 1.0, ease: "none" });
 // Embed in the main composition timeline at the right offset:
 mainTl.add(spinTl, 3);
@@ -166,7 +169,7 @@ mainTl.add(spinTl, 3);
 This is fragile — Remotion's `<Loop>` resets internal state every iteration,
 which GSAP repeat does too, but if the looped child has its own animation,
 you need to be careful that GSAP's `repeatRefresh` is on or off as needed.
-For most simple "spin forever" cases this is fine.
+The finite count is required because HyperFrames seeks a bounded composition frame-by-frame.
 
 ## `<Freeze>`