diff --git a/src/lib/documents/__tests__/extract-reads.test.ts b/src/lib/documents/__tests__/extract-reads.test.ts
index 57fa54549..568f1eba1 100644
--- a/src/lib/documents/__tests__/extract-reads.test.ts
+++ b/src/lib/documents/__tests__/extract-reads.test.ts
@@ -201,16 +201,21 @@ describe("planInboundTextReads", () => {
   const line = (i: number) => `Analyt ${i}    ${i},0    mg/dl    1 - 9`;
   const text = (lines: number) =>
     Array.from({ length: lines }, (_, i) => line(i)).join("\n");
+  const schedule = (calls: number) => ({
+    maxModelCalls: () => calls,
+    arm: async () => undefined,
+  });
+  const noDeadline = schedule(Number.POSITIVE_INFINITY);
 
   it("reads a short text as one read", () => {
-    const plan = planInboundTextReads(text(10), undefined);
+    const plan = planInboundTextReads(text(10), noDeadline);
     expect(plan.args.chunks).toHaveLength(1);
     expect(plan.partial).toBe(false);
   });
 
   it("splits a long text at line boundaries into reads no longer than one read carries", () => {
     const whole = text(400);
-    const plan = planInboundTextReads(whole, undefined);
+    const plan = planInboundTextReads(whole, noDeadline);
     expect(plan.args.chunks.length).toBeGreaterThan(1);
     for (const chunk of plan.args.chunks) {
       expect(chunk.text!.length).toBeLessThanOrEqual(INBOUND_TEXT_READ_CHARS);
@@ -221,10 +226,6 @@ describe("planInboundTextReads", () => {
   });
 
   it("grows the parts when the deadline allows few reads, and reads from the start past twice the size", () => {
-    const schedule = (calls: number) => ({
-      maxModelCalls: () => calls,
-      arm: async () => undefined,
-    });
     // Two reads' worth of calls: the parts grow to hold the text.
     const grown = planInboundTextReads(text(200), schedule(4));
     expect(grown.args.chunks).toHaveLength(2);
@@ -239,7 +240,7 @@ describe("planInboundTextReads", () => {
   });
 
   it("caps the reads of a run with no deadline", () => {
-    const plan = planInboundTextReads(text(4000), undefined);
+    const plan = planInboundTextReads(text(4000), noDeadline);
     expect(plan.args.chunks.length).toBe(OCR_MAX_PAGES);
     expect(plan.partial).toBe(true);
   });
diff --git a/src/lib/documents/extract.ts b/src/lib/documents/extract.ts
index d48803484..361faa61a 100644
--- a/src/lib/documents/extract.ts
+++ b/src/lib/documents/extract.ts
@@ -462,7 +462,7 @@ export interface InboundReads {
 /** A document's text in parts at line boundaries, as many as the run's deadline allows. */
 export function planInboundTextReads(
   text: string,
-  schedule: OcrSchedule | undefined,
+  schedule: OcrSchedule,
 ): InboundReads {
   const { chunks, unreadParts } = planTextReads(
     text,
@@ -483,7 +483,7 @@ export function planInboundTextReads(
  */
 export async function planInboundReads(
   source: InboundReadSource,
-  schedule: OcrSchedule | undefined,
+  schedule: OcrSchedule,
 ): Promise<({ ok: true } & InboundReads) | { ok: false }> {
   if (source.mode === "text") {
     return { ok: true, ...planInboundTextReads(source.text, schedule) };
diff --git a/src/lib/documents/ocr-plan.ts b/src/lib/documents/ocr-plan.ts
index 3fec56366..f46242133 100644
--- a/src/lib/documents/ocr-plan.ts
+++ b/src/lib/documents/ocr-plan.ts
@@ -66,8 +66,7 @@ export const SYNCHRONOUS_READ_SCHEDULE: OcrSchedule = {
 };
 
 /** How many reads the deadline leaves room for. */
-export function maxReadsFor(schedule: OcrSchedule | undefined): number {
-  if (!schedule) return Number.POSITIVE_INFINITY;
+export function maxReadsFor(schedule: OcrSchedule): number {
   return Math.max(
     1,
     Math.floor(schedule.maxModelCalls() / OCR_EXTRACT_MODEL_CALLS),
@@ -130,7 +129,7 @@ export function splitOcrText(
  */
 export function planTextReads(
   text: string,
-  schedule: OcrSchedule | undefined,
+  schedule: OcrSchedule,
   target: number,
 ): { chunks: OcrChunk[]; unreadParts: number } {
   const maxReads = Math.min(maxReadsFor(schedule), OCR_MAX_PAGES);
@@ -186,7 +185,7 @@ export async function planVisionReads(
   bytes: Buffer,
   mime: OcrVisionMime,
   pdfSupported: boolean,
-  schedule: OcrSchedule | undefined,
+  schedule: OcrSchedule,
 ): Promise<OcrVisionPlan> {
   if (mime !== "application/pdf") {
     return {
diff --git a/src/lib/labs/__tests__/ocr-run.test.ts b/src/lib/labs/__tests__/ocr-run.test.ts
index f26d226e7..2ca533791 100644
--- a/src/lib/labs/__tests__/ocr-run.test.ts
+++ b/src/lib/labs/__tests__/ocr-run.test.ts
@@ -94,6 +94,8 @@ const schedule = (maxModelCalls: number) => ({
   maxModelCalls: () => maxModelCalls,
   arm: vi.fn().mockResolvedValue(undefined),
 });
+/** A run whose deadline leaves room for every read. */
+const noDeadline = () => schedule(Number.POSITIVE_INFINITY);
 
 beforeEach(() => {
   vi.clearAllMocks();
@@ -156,6 +158,18 @@ describe("planning the reads", () => {
   });
 });
 
+describe("a scan is always planned against a schedule", () => {
+  it("cannot be started without one", () => {
+    // The scan only runs in the worker, which hands it the run's deadline.
+    // A caller with no schedule would read a twenty-page report as forty
+    // model calls, so the signature leaves no such call to write.
+    const start = () =>
+      // @ts-expect-error -- `schedule` is required
+      executeOcrExtraction({ userId: "u1", input: text(), budget });
+    expect(typeof start).toBe("function");
+  });
+});
+
 describe("text mode", () => {
   it("charges what the provider reported to the provider that served", async () => {
     vi.mocked(runOcrExtraction).mockImplementation(extraction(2345));
@@ -163,6 +177,7 @@ describe("text mode", () => {
       userId: "u1",
       input: text(),
       budget,
+      schedule: noDeadline(),
     });
     expect(out).toEqual({ ok: true, data: { rows: [] } });
     expect(reconcileSpend).toHaveBeenCalledWith(
@@ -177,7 +192,12 @@ describe("text mode", () => {
 
   it("charges the reservation when the provider reported nothing", async () => {
     vi.mocked(runOcrExtraction).mockImplementation(extraction(0));
-    await executeOcrExtraction({ userId: "u1", input: text(), budget });
+    await executeOcrExtraction({
+      userId: "u1",
+      input: text(),
+      budget,
+      schedule: noDeadline(),
+    });
     expect(reconcileSpend).toHaveBeenCalledWith(
       "u1",
       1500,
@@ -210,7 +230,12 @@ describe("text mode", () => {
 
   it("passes the cached share of what was spent to the ledger", async () => {
     vi.mocked(runOcrExtraction).mockImplementation(extraction(3000, 1200));
-    await executeOcrExtraction({ userId: "u1", input: text(), budget });
+    await executeOcrExtraction({
+      userId: "u1",
+      input: text(),
+      budget,
+      schedule: noDeadline(),
+    });
     expect(reconcileSpend).toHaveBeenCalledWith(
       "u1",
       1500,
@@ -231,7 +256,12 @@ describe("text mode", () => {
       expect(await args.reserveRead!()).toBe(true);
       return extraction(20_000)(args);
     });
-    await executeOcrExtraction({ userId: "u1", input: text(), budget });
+    await executeOcrExtraction({
+      userId: "u1",
+      input: text(),
+      budget,
+      schedule: noDeadline(),
+    });
     expect(reserveBudget).toHaveBeenCalledWith(
       "u1",
       8000,
@@ -265,6 +295,7 @@ describe("text mode", () => {
       userId: "u1",
       input: text(),
       budget: { ...budget, owner: "user" },
+      schedule: noDeadline(),
     });
     expect(vi.mocked(reserveBudget).mock.calls[0][3]).toBe(2_000_000);
     expect(vi.mocked(reserveBudget).mock.calls[0][4]).toBe("user");
@@ -293,7 +324,12 @@ describe("text mode", () => {
       answer = await args.reserveRead!();
       return { data: { rows: [] } as never, spentTokens: 0, cachedTokens: 0 };
     });
-    await executeOcrExtraction({ userId: "u1", input: text(), budget });
+    await executeOcrExtraction({
+      userId: "u1",
+      input: text(),
+      budget,
+      schedule: noDeadline(),
+    });
     // 18 500 caught up first (allowed, the day stood at 190 000); the next
     // read is then judged at 208 500 and refused. Booking only the 8 000
     // ceiling, or both in one reservation, would have let it through.
@@ -322,7 +358,12 @@ describe("text mode", () => {
       await args.reserveRead!();
       return { data: { rows: [] } as never, spentTokens: 0, cachedTokens: 0 };
     });
-    await executeOcrExtraction({ userId: "u1", input: text(), budget });
+    await executeOcrExtraction({
+      userId: "u1",
+      input: text(),
+      budget,
+      schedule: noDeadline(),
+    });
     // 20 000 spent, 4 000 of it cached: 16 000 net against 1 500 reserved.
     expect(vi.mocked(reserveBudget).mock.calls[0][1]).toBe(14_500);
   });
@@ -337,6 +378,7 @@ describe("text mode", () => {
       userId: "u1",
       input: text(),
       budget: { ...budget, owner: undefined as never },
+      schedule: noDeadline(),
     });
     expect(answer).toBe(false);
     expect(reserveBudget).not.toHaveBeenCalled();
@@ -347,7 +389,12 @@ describe("text mode", () => {
       new OcrExtractError("x", "budget"),
     );
     expect(
-      await executeOcrExtraction({ userId: "u1", input: text(), budget }),
+      await executeOcrExtraction({
+        userId: "u1",
+        input: text(),
+        budget,
+        schedule: noDeadline(),
+      }),
     ).toMatchObject({ status: 429, errorCode: "labs.ocr.budgetExceeded" });
 
     vi.mocked(runOcrExtraction).mockRejectedValueOnce(
@@ -358,14 +405,24 @@ describe("text mode", () => {
       ),
     );
     expect(
-      await executeOcrExtraction({ userId: "u1", input: text(), budget }),
+      await executeOcrExtraction({
+        userId: "u1",
+        input: text(),
+        budget,
+        schedule: noDeadline(),
+      }),
     ).toMatchObject({ ok: false, errorCode: "consent.ai.required" });
 
     vi.mocked(runOcrExtraction).mockRejectedValueOnce(
       new OcrExtractError("x", "error"),
     );
     expect(
-      await executeOcrExtraction({ userId: "u1", input: text(), budget }),
+      await executeOcrExtraction({
+        userId: "u1",
+        input: text(),
+        budget,
+        schedule: noDeadline(),
+      }),
     ).toMatchObject({ status: 500, errorCode: "aiRuns.failed" });
   });
 
@@ -379,7 +436,12 @@ describe("text mode", () => {
       answer = await args.reserveRead!();
       return extraction(4000)(args);
     });
-    await executeOcrExtraction({ userId: "u1", input: text(), budget });
+    await executeOcrExtraction({
+      userId: "u1",
+      input: text(),
+      budget,
+      schedule: noDeadline(),
+    });
     expect(answer).toBe(false);
     // The refused reservation was handed back by reserveBudget itself; the
     // run settles against the first read's alone.
@@ -399,6 +461,7 @@ describe("text mode", () => {
       userId: "u1",
       input: text("x".repeat(OCR_TEXT_READ_MAX_CHARS + 1)),
       budget,
+      schedule: noDeadline(),
     });
     expect(out).toMatchObject({
       ok: false,
@@ -421,7 +484,12 @@ describe("text mode", () => {
       args.meter!.spent += 900;
       throw new OcrExtractError("x");
     });
-    await executeOcrExtraction({ userId: "u1", input: text(), budget });
+    await executeOcrExtraction({
+      userId: "u1",
+      input: text(),
+      budget,
+      schedule: noDeadline(),
+    });
     expect(reconcileSpend).toHaveBeenCalledWith(
       "u1",
       1500,
@@ -438,6 +506,7 @@ describe("text mode", () => {
       userId: "u1",
       input: text(),
       budget,
+      schedule: noDeadline(),
     });
     expect(out).toMatchObject({
       ok: false,
@@ -462,6 +531,7 @@ describe("text mode", () => {
       userId: "u1",
       input: text(),
       budget,
+      schedule: noDeadline(),
     });
     expect(out).toMatchObject({
       ok: false,
@@ -482,6 +552,7 @@ describe("text mode", () => {
       userId: "u1",
       input: text(),
       budget,
+      schedule: noDeadline(),
     });
     expect(out).toMatchObject({ ok: false, status: 502 });
     expect(JSON.stringify(out)).toContain("configured AI provider");
@@ -563,6 +634,7 @@ describe("vision mode", () => {
       userId: "u1",
       input: pdf(anthropicPick),
       budget,
+      schedule: noDeadline(),
     });
     const args = vi.mocked(runOcrExtraction).mock.calls[0][0];
     expect(args.chunks.map((c) => c.pages)).toEqual([[1], [2], [3], [4]]);
@@ -585,6 +657,7 @@ describe("vision mode", () => {
         userId: "u1",
         input: pdf(anthropicPick),
         budget,
+        schedule: noDeadline(),
       });
       const args = vi.mocked(runOcrExtraction).mock.calls[i][0];
       expect(args.chunks).toHaveLength(1);
@@ -627,6 +700,7 @@ describe("vision mode", () => {
       userId: "u1",
       input: pdf(),
       budget,
+      schedule: noDeadline(),
     });
     expect(out).toEqual({
       ok: true,
@@ -643,6 +717,7 @@ describe("vision mode", () => {
       userId: "u1",
       input: pdf(),
       budget,
+      schedule: noDeadline(),
     });
     expect(out).toMatchObject({
       ok: false,
diff --git a/src/lib/labs/ocr-run.ts b/src/lib/labs/ocr-run.ts
index 629151cc3..75b668be5 100644
--- a/src/lib/labs/ocr-run.ts
+++ b/src/lib/labs/ocr-run.ts
@@ -137,8 +137,11 @@ export async function executeOcrExtraction(args: {
   userId: string;
   input: OcrRunInput;
   budget: AiRunBudget | undefined;
-  /** The run's deadline; absent, the read is planned without one. */
-  schedule?: OcrSchedule;
+  /**
+   * The run's deadline. Required: the scan only runs in the background
+   * worker, and a read planned without a bound could make forty model calls.
+   */
+  schedule: OcrSchedule;
 }): Promise<AiRunOutcome<OcrExtractResponseDto>> {
   const { userId, input, budget, schedule } = args;
   const servedBy = input.pick.entry.providerType as ProviderChainType;
@@ -205,7 +208,7 @@ export async function executeOcrExtraction(args: {
         errorCode: "labs.ocr.tooLarge",
       });
     }
-    await schedule?.arm(parts.length * OCR_EXTRACT_MODEL_CALLS);
+    await schedule.arm(parts.length * OCR_EXTRACT_MODEL_CALLS);
     return read({
       mode: "text",
       chunks: parts.map((text) => ({ text, pages: [] })),
@@ -238,7 +241,7 @@ export async function executeOcrExtraction(args: {
     });
   }
 
-  await schedule?.arm(chunks.length * OCR_EXTRACT_MODEL_CALLS);
+  await schedule.arm(chunks.length * OCR_EXTRACT_MODEL_CALLS);
   const outcome = await read({ mode: "vision", chunks, totalPages });
   return outcome.ok && pageCoverage
     ? { ok: true, data: { ...outcome.data, pageCoverage } }