diff --git a/tests/unit/combo-10597-error-body-logging.test.ts b/tests/unit/combo-10597-error-body-logging.test.ts
index 6df6a2cf49..a18f892716 100644
--- a/tests/unit/combo-10597-error-body-logging.test.ts
+++ b/tests/unit/combo-10597-error-body-logging.test.ts
@@ -48,14 +48,24 @@ function healthy200(model: string) {
       id: "ok",
       object: "chat.completion",
       model,
-      choices: [{ index: 0, message: { role: "assistant", content: "hello from " + model }, finish_reason: "stop" }],
+      choices: [
+        {
+          index: 0,
+          message: { role: "assistant", content: "hello from " + model },
+          finish_reason: "stop",
+        },
+      ],
     }),
     { status: 200, headers: { "Content-Type": "application/json" } }
   );
 }
 
 function makeCombo(models: string[]) {
-  return { name: "test-combo-10597", strategy: "priority", models: models.map((m) => ({ model: m })) };
+  return {
+    name: "test-combo-10597",
+    strategy: "priority",
+    models: models.map((m) => ({ model: m })),
+  };
 }
 
 test("#10597 COMBO failure log must surface the upstream error body, not just the status code", async () => {
@@ -79,7 +89,10 @@ test("#10597 COMBO failure log must surface the upstream error body, not just th
   assert.equal(modelsCalled.length, 2);
 
   const failureLog = warnCalls.find(
-    (c) => typeof c.msg === "string" && c.msg.includes("claude/claude-opus-4-8") && c.msg.includes("failed")
+    (c) =>
+      typeof c.msg === "string" &&
+      c.msg.includes("claude/claude-opus-4-8") &&
+      c.msg.includes("failed")
   );
   assert.ok(failureLog, "expected a COMBO warn log for the failing leg");
 
@@ -89,3 +102,42 @@ test("#10597 COMBO failure log must surface the upstream error body, not just th
     `expected the upstream error body to appear in the COMBO failure log, but got: ${serialized}`
   );
 });
+
+test("transcript-sensitive combo failures omit echoed transcript only from retained logs", async () => {
+  const transcriptSentinel = "PRIVATE_COMBO_ERROR_TRANSCRIPT_SENTINEL";
+  const localWarnCalls: WarnCall[] = [];
+  const modelsCalled: string[] = [];
+  const result = await handleComboChat({
+    body: { model: "test", messages: [{ role: "user", content: "processed video request" }] },
+    combo: makeCombo(["claude/private-video", "openai/private-video-fallback"]),
+    handleSingleModel: async (_body: unknown, modelStr: string) => {
+      modelsCalled.push(modelStr);
+      if (modelsCalled.length === 1) {
+        return new Response(JSON.stringify({ error: { message: transcriptSentinel } }), {
+          status: 400,
+          headers: { "Content-Type": "application/json" },
+        });
+      }
+      return healthy200(modelStr);
+    },
+    log: {
+      info: () => {},
+      debug: () => {},
+      error: () => {},
+      warn: (tag: string, msg: string, meta?: unknown) => {
+        localWarnCalls.push({ tag, msg, meta });
+      },
+    },
+    settings: {},
+    allCombos: [],
+    videoTranscriptSensitive: true,
+  });
+
+  assert.equal(result.status, 200);
+  assert.equal(modelsCalled.length, 2);
+  const retainedFailure = localWarnCalls.find((call) => call.msg.includes("failed, trying next"));
+  assert.ok(retainedFailure);
+  const serialized = JSON.stringify(retainedFailure);
+  assert.equal(serialized.includes(transcriptSentinel), false);
+  assert.match(serialized, /omitted: video transcript/);
+});
diff --git a/tests/unit/combo-context-relay.test.ts b/tests/unit/combo-context-relay.test.ts
index 5e83b460c3..57d3000e31 100644
--- a/tests/unit/combo-context-relay.test.ts
+++ b/tests/unit/combo-context-relay.test.ts
@@ -282,6 +282,52 @@ test("handleComboChat context-relay persists a handoff when codex quota reaches
   assert.equal(saved.fromAccount, connectionId);
 });
 
+test("handleComboChat does not persist a transcript-sensitive context-relay handoff", async () => {
+  const sessionId = "sess-private-video";
+  const connectionId = "conn-private-video";
+  touchSession(sessionId, connectionId);
+  registerCodexConnection(connectionId, {
+    accessToken: "token-private-video",
+    workspaceId: "ws-private-video",
+  });
+
+  let summaryCalls = 0;
+  globalThis.fetch = async (url) => {
+    if (String(url).includes("/backend-api/wham/usage")) return buildQuotaResponse(90);
+    throw new Error(`Unexpected fetch: ${String(url)}`);
+  };
+
+  const result = await handleComboChat({
+    body: {
+      messages: [{ role: "user", content: "guardrail-produced video description" }],
+    },
+    combo: {
+      name: "relay-private-video",
+      strategy: "context-relay",
+      models: ["codex/gpt-5.6-sol"],
+      config: { maxRetries: 0, handoffThreshold: 0.85, handoffProviders: ["codex"] },
+    },
+    handleSingleModel: async (body) => {
+      if (body._omnirouteInternalRequest === "context-handoff") summaryCalls += 1;
+      return okResponse();
+    },
+    isModelAvailable: async () => true,
+    log: createLog(),
+    settings: null,
+    allCombos: null,
+    relayOptions: {
+      sessionId,
+      config: { handoffThreshold: 0.85, handoffProviders: ["codex"] },
+    },
+    videoTranscriptSensitive: true,
+  });
+
+  await new Promise((resolve) => setTimeout(resolve, 75));
+  assert.equal(result.ok, true);
+  assert.equal(summaryCalls, 0);
+  assert.equal(handoffDb.getHandoff(sessionId, "relay-private-video"), null);
+});
+
 test("handleComboChat context-relay respects handoffProviders and skips generation when codex is disabled", async () => {
   const sessionId = "sess-disabled-provider";
   const connectionId = "conn-disabled-provider";
diff --git a/tests/unit/context-handoff.test.ts b/tests/unit/context-handoff.test.ts
index 845f118a5e..c3f09e6179 100644
--- a/tests/unit/context-handoff.test.ts
+++ b/tests/unit/context-handoff.test.ts
@@ -152,6 +152,40 @@ test("maybeGenerateHandoff skips below the warning threshold", async () => {
   assert.equal(handoffDb.getHandoff("sess-low", "relay-combo"), null);
 });
 
+test("maybeGenerateHandoff never summarizes a structurally transcript-sensitive history", async () => {
+  let called = false;
+
+  contextHandoff.maybeGenerateHandoff({
+    sessionId: "sess-private-video",
+    comboName: "relay-private-video",
+    connectionId: "conn-private-video",
+    percentUsed: 0.9,
+    messages: [
+      {
+        role: "user",
+        content: [
+          {
+            transcript: "PRIVATE_CONTEXT_HANDOFF_TRANSCRIPT_SENTINEL",
+            type: "input_video",
+            video_url: "data:video/mp4;base64,AA==",
+          },
+        ],
+      },
+    ],
+    model: "codex/gpt-5.6-sol",
+    expiresAt: null,
+    config: { handoffProviders: ["codex"] },
+    handleSingleModel: async () => {
+      called = true;
+      return new Response("{}", { status: 200 });
+    },
+  });
+
+  await new Promise((resolve) => setTimeout(resolve, 50));
+  assert.equal(called, false);
+  assert.equal(handoffDb.getHandoff("sess-private-video", "relay-private-video"), null);
+});
+
 test("maybeGenerateHandoff persists a structured handoff once the threshold is reached", async () => {
   const calls = [];
 
diff --git a/tests/unit/rejected-request-usage.test.ts b/tests/unit/rejected-request-usage.test.ts
index ed28f36fd6..2842d2531a 100644
--- a/tests/unit/rejected-request-usage.test.ts
+++ b/tests/unit/rejected-request-usage.test.ts
@@ -171,7 +171,6 @@ test("transcript-sensitive rejection omits retained error echoes and request cue
     apiKeyId: "key-transcript-sensitive-rejection",
     apiKeyName: "transcript-sensitive-rejection",
     requestBody,
-    videoTranscriptSensitive: true,
   });
 
   let detail: Awaited<ReturnType<typeof callLogs.getCallLogById>> = null;
diff --git a/tests/unit/request-log-payloads.test.ts b/tests/unit/request-log-payloads.test.ts
index 788cdac557..a5273314c3 100644
--- a/tests/unit/request-log-payloads.test.ts
+++ b/tests/unit/request-log-payloads.test.ts
@@ -22,6 +22,7 @@ const {
   extractVideoTranscriptDescriptionFingerprints,
   fingerprintVideoTranscriptDescription,
   omitVideoTranscriptForLog,
+  resolveVideoTranscriptLogSensitivity,
   VIDEO_TRANSCRIPT_LOG_OMISSION_MARKER,
 } = await import("../../src/lib/guardrails/videoTranscriptLogRedaction.ts");
 const { FORMATS } = await import("../../open-sse/translator/formats.ts");
@@ -596,6 +597,97 @@ test("fails closed when enumerable getters or proxies throw during transcript in
   }
 });
 
+test("fails closed when an enumerable function can replace the retained JSON representation", () => {
+  const privateTranscript = "PRIVATE_TOJSON_VIDEO_TRANSCRIPT_SENTINEL";
+  const payload = {
+    safe: "retained diagnostic",
+    toJSON() {
+      return {
+        transcript: privateTranscript,
+        type: "input_video",
+        video_url: "data:video/mp4;base64,AA==",
+      };
+    },
+  };
+
+  assert.equal(containsVideoTranscriptForLog(payload), true);
+  const omitted = omitVideoTranscriptForLog(payload) as Record<string, unknown>;
+  const serialized = JSON.stringify(omitted);
+
+  assert.equal(serialized.includes(privateTranscript), false);
+  assert.equal(omitted.safe, "retained diagnostic");
+  assert.notEqual(typeof omitted.toJSON, "function");
+});
+
+test("treats explicit malformed and nested video carriers as transcript-sensitive", () => {
+  const privateTranscript = "PRIVATE_MALFORMED_VIDEO_TRANSCRIPT_SENTINEL";
+  const payloads = [
+    {
+      transcript: privateTranscript,
+      type: "input_video",
+    },
+    {
+      transcript: privateTranscript,
+      type: "video_url",
+      video_url: "",
+    },
+    {
+      input_video: {
+        transcript: privateTranscript,
+        url: "data:video/mp4;base64,AA==",
+      },
+      type: "input_video",
+    },
+    {
+      source: { transcript: privateTranscript },
+      type: "video_source",
+    },
+    {
+      source: {
+        media_type: "video/mp4",
+        transcript: privateTranscript,
+      },
+      type: "video",
+    },
+  ];
+
+  for (const payload of payloads) {
+    assert.equal(containsVideoTranscriptForLog(payload), true, JSON.stringify(payload));
+    const serialized = JSON.stringify(omitVideoTranscriptForLog(payload));
+    assert.equal(serialized.includes(privateTranscript), false, serialized);
+    assert.match(serialized, /omitted: video transcript/);
+  }
+});
+
+test("keeps raw request sensitivity after a guardrail removes the original carrier", () => {
+  const rawRequestBody = {
+    messages: [
+      {
+        content: [
+          {
+            transcript: "PRIVATE_RAW_REQUEST_TRANSCRIPT_SENTINEL",
+            type: "input_video",
+            video_url: "data:video/mp4;base64,AA==",
+          },
+        ],
+        role: "user",
+      },
+    ],
+  };
+  const processedBody = {
+    messages: [{ content: "guardrail replaced the media", role: "user" }],
+  };
+
+  assert.equal(resolveVideoTranscriptLogSensitivity({ processedBody, rawRequestBody }), true);
+  assert.equal(
+    resolveVideoTranscriptLogSensitivity({
+      processedBody: { metadata: { transcript: "ordinary audit label" } },
+      rawRequestBody: { metadata: { transcript: "ordinary caller label" } },
+    }),
+    false
+  );
+});
+
 test("fails closed at the aggregate traversal budget before a tail video transcript can leak", () => {
   const privateTranscript = "private over-budget video transcript sentinel";
   const payload: unknown[] = Array.from(
diff --git a/tests/unit/universal-handoff.test.ts b/tests/unit/universal-handoff.test.ts
index 8ef12d4311..81f6b50ddf 100644
--- a/tests/unit/universal-handoff.test.ts
+++ b/tests/unit/universal-handoff.test.ts
@@ -160,6 +160,34 @@ test("providerAllowlist: empty allowlist allows all providers", async () => {
   assert.ok(calls.length > 0, "handleSingleModel MUST be called when allowlist is empty");
 });
 
+test("transcript-sensitive model switches never generate a persistent universal handoff", async () => {
+  const calls: unknown[] = [];
+  maybeGenerateUniversalHandoff({
+    sessionId: "ses_private_video",
+    comboName: "private-video-combo",
+    messages: [{ role: "user", content: "guardrail-produced video description" }],
+    prevModel: "openai/gpt-4o",
+    currModel: "anthropic/claude-3-5-sonnet",
+    videoTranscriptSensitive: true,
+    universalConfig: {
+      ...DEFAULT_UNIVERSAL_HANDOFF_CONFIG,
+      enabled: true,
+      providerAllowlist: [],
+      handoffModel: "anthropic/claude-3-5-sonnet",
+    },
+    handleSingleModel: async (body, modelStr) => {
+      calls.push({ body, modelStr });
+      return new Response(JSON.stringify({ choices: [{ message: { content: "{}" } }] }), {
+        status: 200,
+        headers: { "content-type": "application/json" },
+      });
+    },
+  });
+
+  await waitImmediate();
+  assert.strictEqual(calls.length, 0);
+});
+
 test("providerAllowlist: handoffModel takes precedence over currModel for allowlist check", async () => {
   const calls: unknown[] = [];
   await maybeGenerateUniversalHandoff({