feat(engine): surface protocolTimeout env + flag in Puppeteer timeout errors

Field signal ts=1784047847 (darwin/arm64, 8GB M1, 9 videos + 22 images):
reporter hit Runtime.callFunctionOn timeout and switched to FFmpeg
because the error didn't surface HyperFrames' existing knobs
(PRODUCER_PUPPETEER_PROTOCOL_TIMEOUT_MS env, --protocol-timeout CLI).

Wraps main-render Puppeteer errors matching /Runtime\.callFunctionOn
timed out|Target closed|protocolTimeout/i with an augmented message that
names the effective timeout, the env var, the CLI flag, and the
field-signal shape. Non-matching errors pass through unchanged
(returned as the same instance). Original error preserved via err.cause.

Also adds a dedicated --protocol-timeout row to the CLI docs Flags table
so PRODUCER_PUPPETEER_PROTOCOL_TIMEOUT_MS is discoverable via search.

Signed-off-by: Via <noreply@heygen.com>

packages/engine/src/services/protocolTimeoutErrorHint.test.ts

@@ -0,0 +1,80 @@
+import { describe, expect, it } from "vitest";
+import { augmentProtocolTimeoutError, isProtocolTimeoutError } from "./protocolTimeoutErrorHint.js";
+
+describe("augmentProtocolTimeoutError", () => {
+  it("passes non-timeout errors through unchanged (same instance)", () => {
+    const original = new Error("V8 heap exhausted");
+    const result = augmentProtocolTimeoutError(original, 300_000);
+    expect(result).toBe(original);
+    expect(result.message).toBe("V8 heap exhausted");
+  });
+
+  it("augments Runtime.callFunctionOn timed out with the effective timeout", () => {
+    const original = new Error(
+      "Runtime.callFunctionOn timed out. Increase the 'protocolTimeout' setting.",
+    );
+    const result = augmentProtocolTimeoutError(original, 600_000);
+    expect(result).not.toBe(original);
+    expect(result.message).toContain(original.message);
+    expect(result.message).toContain("HyperFrames effective protocolTimeout: 600000 ms");
+  });
+
+  it("includes both env and CLI hints", () => {
+    const original = new Error("Runtime.callFunctionOn timed out");
+    const result = augmentProtocolTimeoutError(original, 300_000);
+    expect(result.message).toContain("PRODUCER_PUPPETEER_PROTOCOL_TIMEOUT_MS");
+    expect(result.message).toContain("--protocol-timeout");
+  });
+
+  it("preserves err.cause on the augmented error", () => {
+    const original = new Error("Runtime.callFunctionOn timed out");
+    const result = augmentProtocolTimeoutError(original, 300_000);
+    expect((result as Error & { cause?: unknown }).cause).toBe(original);
+  });
+
+  it("augments Target closed errors", () => {
+    const original = new Error("Protocol error (Runtime.callFunctionOn): Target closed.");
+    const result = augmentProtocolTimeoutError(original, 300_000);
+    expect(result).not.toBe(original);
+    expect(result.message).toContain("HyperFrames effective protocolTimeout");
+  });
+
+  it("matches the protocolTimeout keyword case-insensitively", () => {
+    const original = new Error("some upstream saying PROTOCOLTIMEOUT was hit");
+    const result = augmentProtocolTimeoutError(original, 300_000);
+    expect(result).not.toBe(original);
+  });
+
+  it("coerces non-Error thrown values into Error without augmenting", () => {
+    const result = augmentProtocolTimeoutError("plain string failure", 300_000);
+    expect(result).toBeInstanceOf(Error);
+    expect(result.message).toBe("plain string failure");
+    // Not augmented: coerced string doesn't match the protocol-timeout regex.
+    expect(result.message).not.toContain("HyperFrames effective protocolTimeout");
+  });
+
+  it("mentions the field-signal shape reporters hit", () => {
+    const original = new Error("Runtime.callFunctionOn timed out");
+    const result = augmentProtocolTimeoutError(original, 300_000);
+    expect(result.message).toContain("ts=1784047847");
+    expect(result.message).toContain("FFmpeg-only encoding");
+  });
+});
+
+describe("isProtocolTimeoutError", () => {
+  it("returns true for matching messages", () => {
+    expect(isProtocolTimeoutError(new Error("Runtime.callFunctionOn timed out"))).toBe(true);
+    expect(isProtocolTimeoutError(new Error("Target closed"))).toBe(true);
+    expect(isProtocolTimeoutError("protocolTimeout exceeded")).toBe(true);
+  });
+
+  it("returns false for non-matching messages", () => {
+    expect(isProtocolTimeoutError(new Error("V8 heap exhausted"))).toBe(false);
+    expect(isProtocolTimeoutError(new Error("Navigation timeout of 60000 ms exceeded"))).toBe(
+      false,
+    );
+    expect(isProtocolTimeoutError(null)).toBe(false);
+    expect(isProtocolTimeoutError(undefined)).toBe(false);
+    expect(isProtocolTimeoutError(42)).toBe(false);
+  });
+});

packages/engine/src/services/protocolTimeoutErrorHint.ts

@@ -0,0 +1,47 @@
+/**
+ * Augment Puppeteer CDP protocol-timeout errors with actionable guidance that
+ * points at the HyperFrames-specific knobs. Puppeteer's stock error text
+ * ("Runtime.callFunctionOn timed out. Increase the 'protocolTimeout' setting")
+ * doesn't tell the user which env var / CLI flag raises this timeout in
+ * HyperFrames, or what the currently-applied effective value is — so field
+ * reporters have hit this class of failure, given up, and switched to
+ * FFmpeg-only encoding rather than raise a knob they didn't know existed
+ * (field signal ts=1784047847).
+ *
+ * The helper is deliberately conservative:
+ *   - Only augments errors whose message matches known protocol-timeout
+ *     strings (`Runtime.callFunctionOn timed out`, `Target closed`,
+ *     `protocolTimeout`).
+ *   - Non-matching errors are returned unchanged (same instance).
+ *   - Non-Error inputs are coerced with `new Error(String(err))` so callers
+ *     get a well-typed `Error` back regardless of what was thrown.
+ *   - The original error is preserved via `err.cause`, so stack introspection
+ *     and downstream logging still see the raw Puppeteer message.
+ */
+
+const PROTOCOL_TIMEOUT_MATCHER = /Runtime\.callFunctionOn timed out|Target closed|protocolTimeout/i;
+
+export function augmentProtocolTimeoutError(err: unknown, effectiveTimeoutMs: number): Error {
+  if (!(err instanceof Error)) return new Error(String(err));
+  if (!PROTOCOL_TIMEOUT_MATCHER.test(err.message)) return err;
+  const augmented = new Error(
+    `${err.message}\n\n` +
+      `HyperFrames effective protocolTimeout: ${effectiveTimeoutMs} ms.\n\n` +
+      `To raise the timeout:\n` +
+      `  Env: PRODUCER_PUPPETEER_PROTOCOL_TIMEOUT_MS=<higher-ms>\n` +
+      `  CLI: --protocol-timeout <higher-ms>\n\n` +
+      `Field signal ts=1784047847: this class of failure appears on RAM-pressured hosts with heavy-asset compositions (9+ videos + 20+ images). If raising the timeout doesn't help, consider FFmpeg-only encoding.`,
+  );
+  (augmented as Error & { cause?: unknown }).cause = err;
+  return augmented;
+}
+
+/**
+ * Predicate variant: exposed for callers that only need to classify an error
+ * (e.g. observability, tests) without materialising an augmented Error. Uses
+ * the same matcher as the augmentation path so the two never drift.
+ */
+export function isProtocolTimeoutError(err: unknown): boolean {
+  const message = err instanceof Error ? err.message : typeof err === "string" ? err : "";
+  return PROTOCOL_TIMEOUT_MATCHER.test(message);
+}