diff --git a/docs/ida-provider.md b/docs/ida-provider.md
index b7bcb68e22..32ba0504dc 100644
--- a/docs/ida-provider.md
+++ b/docs/ida-provider.md
@@ -92,7 +92,7 @@ Use a package version that actually includes this adapter; repository main can b
 {"name":"close_binary","arguments":{}}
 ```
 
-Opening an MCP target starts its selected provider session; headless opening waits for auto-analysis. Set the agent's MCP request deadline long enough for the target. The registration's optional `timeoutMs` defaults to 300000 for upstream requests. Cancellation drains the current upstream request before cleanup; it does not force-stop GUI analysis. An open request that times out without a completed response retains the private workspace because worker inventory alone cannot prove the request has stopped. `binary_session` reports actual tool availability. Repeated doctor/setup calls are unnecessary when the registration already works.
+Opening an MCP target starts its selected provider session; headless opening waits for auto-analysis. Set the agent's MCP request deadline long enough for the target. The registration's optional `timeoutMs` defaults to 300000 for upstream requests. A freshly opened headless worker can briefly report `status: "busy"` from `server_health`; REA re-reads the health every 100 ms until the worker answers, the caller cancels, or `timeoutMs` has elapsed since the first read. Only expiry while the worker is still busy produces a retryable `provider_timeout`; no further read is started once the deadline has passed. That error names the busy tool of the last observation, or `unknown` when the worker reported none or a value that is not tool-name-shaped. Cancellation during the wait produces `cancelled`. Any other unexpected health payload, including a busy payload with an invalid shape, remains `unreadable_output`. Cancellation drains the current upstream request before cleanup; it does not force-stop GUI analysis. An open request that times out without a completed response retains the private workspace because worker inventory alone cannot prove the request has stopped. `binary_session` reports actual tool availability. Repeated doctor/setup calls are unnecessary when the registration already works.
 
 For guided registration, set `REA_IDA_MCP_CONFIG` before `rea setup --client <client>`. Setup includes that file reference in its reviewed plan and preserves it after approval; it does not copy upstream credentials into the agent configuration. `rea doctor --provider ida --json` validates the registration without starting IDA and explicitly leaves runtime compatibility and target binding for analysis.
 
@@ -110,4 +110,4 @@ Complete body ranges, typed reference edges, CFG, referenced data, source locals
 
 Run `npm run verify:ida -- --target /absolute/path/to/program --procedure main` with a configured upstream server. It exercises production CLI and MCP tools, validates their output contracts and Evidence, checks original-input preservation and session cleanup, and keeps local target data out of its console summary. Supply `--package-root` to verify an extracted or installed package. See [testing](testing.md) for the distinction between adapter tests and real-provider evidence.
 
-The initial real workflows use stdio registrations for the legacy Windows GUI profile and a Windows x64 headless supervisor with IDA 9.3. Streamable HTTP is tested against a loopback MCP fixture with the pinned client SDK; a real IDA HTTP-supervisor workflow remains unverified. Linux/macOS headless engine operation, other IDA releases, architectures, and modern attached GUI tools require their corresponding real workflows before support is claimed.
+The initial real workflows use stdio registrations for the legacy Windows GUI profile and a Windows x64 headless supervisor with IDA 9.3. The headless workflow has also passed on macOS arm64 with IDA Professional 9.1 (build 9.1.250226) against the same upstream commit `c133c3853faa111a9b00ee615c013b720d0c4acd`, using a source-built arm64 Mach-O fixture; Mach-O C symbols carry a leading underscore, so the procedure name is `_rea_fixture_add`. Streamable HTTP is tested against a loopback MCP fixture with the pinned client SDK; a real IDA HTTP-supervisor workflow remains unverified. Linux headless engine operation, other IDA releases, architectures, and modern attached GUI tools require their corresponding real workflows before support is claimed.
diff --git a/docs/testing.md b/docs/testing.md
index 4d8f7793b2..887d601b45 100644
--- a/docs/testing.md
+++ b/docs/testing.md
@@ -739,9 +739,15 @@ entries, external callees, target switches, cancellation draining, snapshot
 replay exclusion, ownership failures, and incomplete cleanup. They do not
 establish real IDA operation. The initial real workflows cover legacy upstream
 1.4.0 on a Windows GUI and the modern supervisor at upstream commit
-`c133c3853faa111a9b00ee615c013b720d0c4acd` with Windows x64 IDA 9.3.
-Linux/macOS headless, modern attached GUI tools, other engine versions and
-architectures remain unverified; see the [provider guide](ida-provider.md).
+`c133c3853faa111a9b00ee615c013b720d0c4acd` with Windows x64 IDA 9.3, and the
+headless profile on macOS arm64 with IDA Professional 9.1 (build 9.1.250226)
+at the same upstream commit, using `tests/conformance/ida/inventory.c` built
+with `clang -O0 -arch arm64` and the procedure `_rea_fixture_add` (Mach-O C
+symbols carry a leading underscore). Before the headless session waited out
+the transient `busy` health a worker can report right after opening, that lane
+failed intermittently on that host. Linux headless, modern attached GUI tools,
+other engine versions and architectures remain unverified; see the
+[provider guide](ida-provider.md).
 
 ## DOS Ghidra analysis
 
diff --git a/src/ida/IdaBusyHealth.test.ts b/src/ida/IdaBusyHealth.test.ts
new file mode 100644
index 0000000000..512cf78a6a
--- /dev/null
+++ b/src/ida/IdaBusyHealth.test.ts
@@ -0,0 +1,133 @@
+import { expect, it } from "vitest";
+import type { JsonValue } from "../domain/jsonValue.js";
+import type { IdaMcpConnection } from "./IdaMcpConnection.js";
+import { readSettledHealth } from "./IdaBusyHealth.js";
+
+const busy = (tool: string): JsonValue => ({
+  status: "busy",
+  busy_tool: tool,
+  busy_sec: 0,
+  queued_calls: 0,
+});
+const ok: JsonValue = { status: "ok", module: "target" };
+
+/** Connection that answers each health read from a script and counts reads. */
+const scripted = (answers: readonly JsonValue[]) => {
+  const reads: number[] = [];
+  const connection: IdaMcpConnection = {
+    connect: async () => [],
+    serverInfo: () => null,
+    close: async () => undefined,
+    call: async () => {
+      reads.push(reads.length);
+      const answer = answers[Math.min(reads.length - 1, answers.length - 1)];
+      if (answer === undefined) throw new Error("empty script");
+      return answer;
+    },
+  };
+  return { connection, reads };
+};
+
+/** Virtual clock: sleeping advances time, nothing really waits. */
+const virtualClock = (onSleep?: (ms: number) => void) => {
+  let time = 0;
+  const sleeps: number[] = [];
+  return {
+    sleeps,
+    clock: {
+      now: () => time,
+      delay: async (ms: number) => {
+        sleeps.push(ms);
+        time += ms;
+        onSleep?.(ms);
+      },
+    },
+  };
+};
+
+it("sleeps the fixed retry delay between busy reads and returns the settled answer", async () => {
+  const { connection, reads } = scripted([busy("a"), busy("a"), ok]);
+  const { clock, sleeps } = virtualClock();
+
+  const raw = await readSettledHealth(connection, {
+    database: "db",
+    timeoutMs: 10_000,
+    clock,
+  });
+
+  expect(raw, "the settled payload is returned unchanged").toEqual(ok);
+  expect(reads.length, "one read per poll").toBe(3);
+  expect(sleeps, "two fixed 100 ms pauses").toEqual([100, 100]);
+});
+
+it("clamps the last pause to the remaining budget and stops without another read at expiry", async () => {
+  const { connection, reads } = scripted([busy("config_json_get")]);
+  const { clock, sleeps } = virtualClock();
+
+  const failure = await readSettledHealth(connection, {
+    database: "db",
+    timeoutMs: 350,
+    clock,
+  }).catch((cause: unknown) => cause);
+
+  expect(sleeps, "three full pauses, then the 50 ms remainder").toEqual([
+    100, 100, 100, 50,
+  ]);
+  expect(reads.length, "no read is started once the budget is spent").toBe(4);
+  expect(failure, "expiry while busy is a timeout").toMatchObject({
+    _tag: "AnalysisTimeoutError",
+    timeoutMs: 350,
+  });
+});
+
+it("does not read again when the only pause consumes the whole budget", async () => {
+  const { connection, reads } = scripted([busy("config_json_get")]);
+  const { clock } = virtualClock();
+
+  const failure = await readSettledHealth(connection, {
+    database: "db",
+    timeoutMs: 100,
+    clock,
+  }).catch((cause: unknown) => cause);
+
+  expect(reads.length, "the single read before the pause is the only one").toBe(
+    1,
+  );
+  expect(failure, "the last busy payload ends the wait").toMatchObject({
+    _tag: "AnalysisTimeoutError",
+  });
+});
+
+it("reports the busy tool of the last observation", async () => {
+  const { connection } = scripted([busy("first_tool"), busy("last_tool")]);
+  const { clock } = virtualClock();
+
+  const failure = await readSettledHealth(connection, {
+    database: "db",
+    timeoutMs: 150,
+    clock,
+  }).catch((cause: unknown) => cause);
+
+  expect(failure, "the operation names the tool seen last").toMatchObject({
+    operation: "server_health: headless worker still busy in last_tool",
+    cause: busy("last_tool"),
+  });
+});
+
+it("rejects without another read when the signal aborts after the pause has fulfilled", async () => {
+  const controller = new AbortController();
+  const { connection, reads } = scripted([busy("config_json_get")]);
+  const { clock } = virtualClock(() => controller.abort());
+
+  const failure = await readSettledHealth(connection, {
+    database: "db",
+    timeoutMs: 10_000,
+    signal: controller.signal,
+    clock,
+  }).catch((cause: unknown) => cause);
+
+  expect(reads.length, "the abort wins over the next read").toBe(1);
+  expect(failure, "the abort is surfaced, not a timeout").toMatchObject({
+    name: "AbortError",
+  });
+});
diff --git a/src/ida/IdaBusyHealth.ts b/src/ida/IdaBusyHealth.ts
new file mode 100644
index 0000000000..144aa8e526
--- /dev/null
+++ b/src/ida/IdaBusyHealth.ts
@@ -0,0 +1,74 @@
+import { setTimeout as sleep } from "node:timers/promises";
+import { AnalysisTimeoutError } from "../domain/analysisErrorCore.js";
+import type { JsonValue } from "../domain/jsonValue.js";
+import type { IdaMcpConnection } from "./IdaMcpConnection.js";
+import { busyHealthSchema } from "./IdaProtocolValues.js";
+
+/** Pause between health reads while a freshly opened worker reports itself busy. */
+const BUSY_HEALTH_RETRY_MS = 100;
+/** Only a tool-name-shaped value is repeated; other producer text is not echoed into errors. */
+const BUSY_TOOL_NAME = /^[A-Za-z0-9_.:-]{1,64}$/u;
+
+/** Time source and pause used by the wait; tests substitute a virtual clock. */
+export interface BusyHealthClock {
+  now(): number;
+  delay(ms: number, signal: AbortSignal | undefined): Promise<void>;
+}
+
+const monotonicClock: BusyHealthClock = {
+  now: () => performance.now(),
+  delay: (ms, signal) => sleep(ms, undefined, { signal }),
+};
+
+const busyToolName = (tool: string | undefined): string =>
+  tool !== undefined && BUSY_TOOL_NAME.test(tool) ? tool : "unknown";
+
+const isBusyStatus = (raw: JsonValue): boolean =>
+  typeof raw === "object" &&
+  raw !== null &&
+  !Array.isArray(raw) &&
+  raw["status"] === "busy";
+
+/**
+ * Reads `server_health` until the worker stops reporting a transient busy
+ * state. The wait ends when the worker answers, the caller aborts, or the
+ * registration's request deadline has elapsed; once it has elapsed no further
+ * read is started and the last busy observation is reported. Any other payload
+ * is returned for the caller's strict parse, except an invalid busy payload,
+ * which keeps its own diagnostic.
+ */
+export const readSettledHealth = async (
+  connection: IdaMcpConnection,
+  {
+    database,
+    timeoutMs,
+    signal,
+    clock = monotonicClock,
+  }: {
+    readonly database: string;
+    readonly timeoutMs: number;
+    readonly signal?: AbortSignal | undefined;
+    readonly clock?: BusyHealthClock;
+  },
+): Promise<JsonValue> => {
+  const started = clock.now();
+  const remaining = (): number => timeoutMs - (clock.now() - started);
+  for (;;) {
+    const raw = await connection.call("server_health", { database });
+    const busy = busyHealthSchema.safeParse(raw);
+    if (!busy.success) {
+      if (isBusyStatus(raw)) throw busy.error;
+      return raw;
+    }
+    const expired = (): AnalysisTimeoutError =>
+      new AnalysisTimeoutError(
+        `server_health: headless worker still busy in ${busyToolName(busy.data.busy_tool)}`,
+        timeoutMs,
+        { cause: raw },
+      );
+    if (remaining() <= 0) throw expired();
+    await clock.delay(Math.min(BUSY_HEALTH_RETRY_MS, remaining()), signal);
+    signal?.throwIfAborted();
+    if (remaining() <= 0) throw expired();
+  }
+};
diff --git a/src/ida/IdaProtocolValues.ts b/src/ida/IdaProtocolValues.ts
index c0c92bb02c..ade459a20a 100644
--- a/src/ida/IdaProtocolValues.ts
+++ b/src/ida/IdaProtocolValues.ts
@@ -37,6 +37,13 @@ export const legacyMetadataSchema = z
     base: idaAddressSchema,
   })
   .passthrough();
+/** A worker that is still busy right after opening reports this transient shape instead of its identity. */
+export const busyHealthSchema = z
+  .object({
+    status: z.literal("busy"),
+    busy_tool: z.string().optional(),
+  })
+  .passthrough();
 export const modernHealthSchema = z
   .object({
     status: z.literal("ok"),
diff --git a/src/ida/IdaSessionClient.test.ts b/src/ida/IdaSessionClient.test.ts
index f1bb054670..d190ecc720 100644
--- a/src/ida/IdaSessionClient.test.ts
+++ b/src/ida/IdaSessionClient.test.ts
@@ -8,14 +8,18 @@ import {
 } from "../../tests/fixtures/idaMcp.js";
 import { IdaSessionClient } from "./IdaSessionClient.js";
 import { functionDossierSchema } from "../domain/hopperValues.js";
-import { jsonValueSchema } from "../domain/jsonValue.js";
+import { jsonValueSchema, type JsonValue } from "../domain/jsonValue.js";
+import { projectAnalysisError } from "../domain/analysisErrorProjection.js";
 
 const roots: string[] = [];
 afterEach(async () => {
   for (const root of roots.splice(0))
     await rm(root, { recursive: true, force: true });
 });
-const fixture = async (mode: "attached" | "headless" = "attached") => {
+const fixture = async (
+  mode: "attached" | "headless" = "attached",
+  timeoutMs = 1000,
+) => {
   const { root, target } = await createIdaTarget();
   roots.push(root);
   const producer = new RecordingIdaMcp(target, mode);
@@ -25,7 +29,7 @@ const fixture = async (mode: "attached" | "headless" = "attached") => {
       args: [],
       env: {},
       mode,
-      timeoutMs: 1000,
+      timeoutMs,
       workspaceRoot: root,
     },
     target,
@@ -328,6 +332,291 @@ describe("attached IDA function observations", () => {
   });
 });
 
+const busyHealth = (busyTool?: JsonValue): JsonValue => ({
+  status: "busy",
+  uptime_sec: 1.041,
+  ...(busyTool === undefined ? {} : { busy_tool: busyTool }),
+  busy_sec: 0,
+  queued_calls: 0,
+});
+const healthCalls = (producer: { calls: { name: string }[] }) =>
+  producer.calls.filter(({ name }) => name === "server_health").length;
+
+const expectCleanClose = async (
+  producer: { closes: number },
+  client: { close: () => Promise<{ ok: boolean }> },
+): Promise<void> => {
+  expect((await client.close()).ok, "the owned worker is released").toBe(true);
+  expect(producer.closes, "the upstream connection is closed once").toBe(1);
+};
+
+describe("headless IDA transient busy health", () => {
+  it("re-reads server_health until the worker reports ok", async () => {
+    const { producer, client } = await fixture("headless");
+    let busyReads = 2;
+    producer.overrideCall = (name) =>
+      name === "server_health" && busyReads-- > 0
+        ? busyHealth("config_json_get")
+        : undefined;
+
+    const result = await client.execute("health", {});
+
+    expect(result.ok, "a transient busy worker is waited out").toBe(true);
+    expect(
+      healthCalls(producer),
+      "two busy reads and the ok read that settles the identity",
+    ).toBe(3);
+    await expectCleanClose(producer, client);
+  });
+
+  it("returns a retryable timeout naming the busy tool at the registration deadline", async () => {
+    const { producer, client } = await fixture("headless", 300);
+    const busy = busyHealth("config_json_get");
+    producer.overrideCall = (name) =>
+      name === "server_health" ? busy : undefined;
+    const started = Date.now();
+
+    const result = await client.execute("health", {});
+    const elapsed = Date.now() - started;
+
+    if (result.ok) throw new Error("expected a busy timeout");
+    expect(result.error._tag, "the neutral timeout class is used").toBe(
+      "AnalysisTimeoutError",
+    );
+    const projected = projectAnalysisError(result.error);
+    expect(projected.code, "the outcome is a provider timeout").toBe(
+      "provider_timeout",
+    );
+    expect(projected.retryable, "the caller may retry").toBe(true);
+    expect(
+      projected.details,
+      "the observed busy tool is named exactly in the operation",
+    ).toMatchObject({
+      operation: "server_health: headless worker still busy in config_json_get",
+      timeout_ms: 300,
+    });
+    expect(
+      result.error.message,
+      "the error message names the busy tool",
+    ).toContain("config_json_get");
+    expect(
+      `${result.error.message} ${projected.message}`,
+      "no Hopper wording leaks in",
+    ).not.toContain("Hopper");
+    expect(result.error.cause, "the raw busy payload is the cause").toEqual(
+      busy,
+    );
+    expect(
+      elapsed,
+      "the wait runs to the deadline, not less",
+    ).toBeGreaterThanOrEqual(290);
+    expect(
+      healthCalls(producer),
+      "reads are spaced by the retry delay, not a tight loop",
+    ).toBeLessThanOrEqual(6);
+    await expectCleanClose(producer, client);
+  });
+
+  it("never invents a busy tool the worker did not report", async () => {
+    const { producer, client } = await fixture("headless", 300);
+    producer.overrideCall = (name) =>
+      name === "server_health" ? busyHealth() : undefined;
+
+    const result = await client.execute("health", {});
+
+    if (result.ok) throw new Error("expected a busy timeout");
+    expect(
+      projectAnalysisError(result.error).details,
+      "an omitted busy_tool is reported as exactly unknown",
+    ).toMatchObject({
+      operation: "server_health: headless worker still busy in unknown",
+    });
+    await expectCleanClose(producer, client);
+  });
+
+  it.each([
+    ["free-form text", "token=abc123 /private/home/user secret"],
+    ["an over-long name", "x".repeat(200)],
+  ])(
+    "reports %s from the worker as unknown instead of echoing it",
+    async (_label, tool) => {
+      const { producer, client } = await fixture("headless", 300);
+      producer.overrideCall = (name) =>
+        name === "server_health" ? busyHealth(tool) : undefined;
+
+      const result = await client.execute("health", {});
+
+      if (result.ok) throw new Error("expected a busy timeout");
+      expect(
+        projectAnalysisError(result.error).details,
+        "only a tool-name-shaped value is repeated",
+      ).toMatchObject({
+        operation: "server_health: headless worker still busy in unknown",
+      });
+      expect(
+        result.error.message,
+        "the producer text never reaches the error message",
+      ).not.toContain(tool);
+      await expectCleanClose(producer, client);
+    },
+  );
+
+  it("ends the wait at once when the caller aborts", async () => {
+    const { producer, client } = await fixture("headless", 30_000);
+    producer.overrideCall = (name) =>
+      name === "server_health" ? busyHealth("config_json_get") : undefined;
+    const controller = new AbortController();
+    const started = Date.now();
+    const call = client.execute("health", {}, { signal: controller.signal });
+    while (healthCalls(producer) < 2) {
+      if (Date.now() - started > 5_000) throw new Error("never polled");
+      await new Promise((resolve) => setTimeout(resolve, 10));
+    }
+
+    controller.abort();
+    const result = await call;
+
+    if (result.ok) throw new Error("expected cancellation");
+    expect(result.error._tag, "cancellation keeps today's outcome").toBe(
+      "AnalysisCancelledError",
+    );
+    expect(
+      Date.now() - started,
+      "the wait does not run to the registration deadline",
+    ).toBeLessThan(5_000);
+    await expectCleanClose(producer, client);
+  });
+});
+
+describe("headless IDA busy health after an operation", () => {
+  const withInventory = (
+    producer: RecordingIdaMcp,
+    afterObservation: (read: number) => JsonValue | undefined,
+  ) => {
+    let health = 0;
+    producer.overrideCall = (name) => {
+      if (name === "list_funcs")
+        return [
+          {
+            data: [{ addr: "0x1000", name: "main", size: "0x20" }],
+            next_offset: null,
+          },
+        ];
+      if (name !== "server_health") return undefined;
+      health += 1;
+      return health < 2 ? undefined : afterObservation(health);
+    };
+  };
+
+  it("waits out a busy observation taken after the operation", async () => {
+    const { producer, client } = await fixture("headless");
+    withInventory(producer, (read) =>
+      read === 2 ? busyHealth("config_json_get") : undefined,
+    );
+
+    const result = await client.execute("list_procedures", {});
+
+    expect(result.ok, "the operation succeeds once the worker settles").toBe(
+      true,
+    );
+    expect(healthCalls(producer), "before, busy after, ok after").toBe(3);
+    await expectCleanClose(producer, client);
+  });
+
+  it("maps a cancellation during that wait to cancelled", async () => {
+    const { producer, client } = await fixture("headless", 30_000);
+    withInventory(producer, () => busyHealth("config_json_get"));
+    const controller = new AbortController();
+    const call = client.execute(
+      "list_procedures",
+      {},
+      { signal: controller.signal },
+    );
+    const started = Date.now();
+    while (healthCalls(producer) < 3) {
+      if (Date.now() - started > 5_000) throw new Error("never polled");
+      await new Promise((resolve) => setTimeout(resolve, 10));
+    }
+
+    controller.abort();
+    const result = await call;
+
+    if (result.ok) throw new Error("expected cancellation");
+    expect(result.error._tag, "the after-observation wait is cancellable").toBe(
+      "AnalysisCancelledError",
+    );
+    await expectCleanClose(producer, client);
+  });
+});
+
+describe("headless IDA non-busy health payloads", () => {
+  it.each([
+    ["an unknown status", { status: "starting" }],
+    ["a non-string busy_tool", busyHealth(5)],
+    ["a payload without a status", { uptime_sec: 1 }],
+  ])(
+    "keeps %s as unreadable output without waiting",
+    async (_label, payload) => {
+      const { producer, client } = await fixture("headless");
+      producer.overrideCall = (name) =>
+        name === "server_health" ? jsonValueSchema.parse(payload) : undefined;
+
+      const result = await client.execute("health", {});
+
+      if (result.ok) throw new Error("expected unreadable output");
+      expect(
+        projectAnalysisError(result.error).code,
+        "only the narrow busy shape enters the wait",
+      ).toBe("unreadable_output");
+      expect(healthCalls(producer), "no re-read happened").toBe(1);
+      await expectCleanClose(producer, client);
+    },
+  );
+
+  it("keeps the busy-shape reason when a busy payload is invalid", async () => {
+    const { producer, client } = await fixture("headless");
+    producer.overrideCall = (name) =>
+      name === "server_health" ? busyHealth(5) : undefined;
+
+    const result = await client.execute("health", {});
+
+    if (result.ok) throw new Error("expected unreadable output");
+    expect(
+      projectAnalysisError(result.error).details,
+      "the diagnostic names the invalid busy_tool, not the ok-schema fields",
+    ).toMatchObject({ reason: expect.stringContaining("busy_tool") });
+    expect(
+      JSON.stringify(projectAnalysisError(result.error).details),
+      "the generic ok-schema field errors are not reported for a busy payload",
+    ).not.toContain("input_path");
+    await expectCleanClose(producer, client);
+  });
+
+  it("stops waiting as soon as a later read is malformed", async () => {
+    const { producer, client } = await fixture("headless");
+    let reads = 0;
+    producer.overrideCall = (name) =>
+      name === "server_health"
+        ? reads++ === 0
+          ? busyHealth("config_json_get")
+          : busyHealth(5)
+        : undefined;
+
+    const result = await client.execute("health", {});
+
+    if (result.ok) throw new Error("expected unreadable output");
+    expect(
+      projectAnalysisError(result.error).code,
+      "a malformed re-read is not treated as busy",
+    ).toBe("unreadable_output");
+    expect(
+      healthCalls(producer),
+      "exactly the busy read and the bad read",
+    ).toBe(2);
+    await expectCleanClose(producer, client);
+  });
+});
+
 describe("headless IDA lifecycle boundaries", () => {
   it("never closes an unowned worker even when open echoes the requested private identity", async () => {
     const { producer, client } = await fixture("headless");
diff --git a/src/ida/IdaSessionClient.ts b/src/ida/IdaSessionClient.ts
index d4e51d26ed..48920a7256 100644
--- a/src/ida/IdaSessionClient.ts
+++ b/src/ida/IdaSessionClient.ts
@@ -20,6 +20,7 @@ import { jsonValueSchema, type JsonValue } from "../domain/jsonValue.js";
 import { err, ok, type Result } from "../domain/result.js";
 import type { IdaConfiguration } from "./IdaConfiguration.js";
 import type { IdaMcpConnection } from "./IdaMcpConnection.js";
+import { readSettledHealth } from "./IdaBusyHealth.js";
 import { IdaOperationRunner } from "./IdaOperationRunner.js";
 import {
   IDA_LIMITATIONS,
@@ -183,7 +184,7 @@ export class IdaSessionClient implements AnalysisClient {
       );
     try {
       await this.#start();
-      const before = await this.#observe();
+      const before = await this.#observe(options);
       if (wasCancelled(options))
         return err(new AnalysisCancelledError(operation));
       if (operation === "health") return this.#health(before);
@@ -200,7 +201,7 @@ export class IdaSessionClient implements AnalysisClient {
       const result = await runner.run(operation, parameters);
       if (wasCancelled(options))
         return err(new AnalysisCancelledError(operation));
-      const after = await this.#observe();
+      const after = await this.#observe(options);
       if (wasCancelled(options))
         return err(new AnalysisCancelledError(operation));
       return ok(
@@ -339,7 +340,7 @@ export class IdaSessionClient implements AnalysisClient {
     }
   }
 
-  async #observe(): Promise<JsonValue> {
+  async #observe(options?: ExecutionOptions): Promise<JsonValue> {
     let identity: string;
     if (this.config.mode === "attached") {
       const raw = await this.connection.call("get_metadata", {});
@@ -359,8 +360,10 @@ export class IdaSessionClient implements AnalysisClient {
         throw new AnalysisProtocolError(
           "IDA headless session has no database binding.",
         );
-      const raw = await this.connection.call("server_health", {
+      const raw = await readSettledHealth(this.connection, {
         database: this.#database,
+        timeoutMs: this.config.timeoutMs,
+        signal: options?.signal,
       });
       const metadata = modernHealthSchema.parse(raw);
       if (