diff --git a/src/application/frida/FridaInstrumentationService.test.ts b/src/application/frida/FridaInstrumentationService.test.ts
index 482b63c7cc..73d8220c97 100644
--- a/src/application/frida/FridaInstrumentationService.test.ts
+++ b/src/application/frida/FridaInstrumentationService.test.ts
@@ -368,11 +368,186 @@ it("retains an observed spawn resume after the target detaches before cancellati
     });
 });
 
+it("returns typed partial Evidence when cancellation arrives during successful final cleanup", async () => {
+  const controller = new AbortController();
+  const abortReason = new Error("cancelled during final detach");
+  const script = {
+    ...createScriptObservation(),
+    messages: [{ type: "send", payload: "completed-before-detach" }],
+  };
+  let closes = 0;
+  const service = new FridaInstrumentationService(
+    createProvider({
+      async loadScript() {
+        return { ok: true, value: script };
+      },
+      async closeSession() {
+        closes += 1;
+        controller.abort(abortReason);
+        return { ok: true, value: { targetResumeObserved: true } };
+      },
+    }),
+  );
+
+  const result = await service.instrument(
+    {
+      mode: "spawn",
+      deviceId: "local",
+      program: "/fixture",
+      source: {
+        sourceKind: "inline",
+        source: "send('completed-before-detach')",
+      },
+      durationMs: 0,
+    },
+    controller.signal,
+  );
+
+  expect(result.ok).toBe(false);
+  if (result.ok) return;
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(abortReason);
+  expect(result.error.partialObservation).toMatchObject({
+    normalized_result: {
+      messages: script.messages,
+      source_sha256: script.sourceSha256,
+      cleanup_error: null,
+      target_state_before_cleanup: "paused",
+      target_resume_observed: true,
+      instrumentation_cleanup: "released",
+      target_liveness_after_cleanup: "unknown",
+    },
+  });
+  expect(closes).toBe(1);
+});
+
+it("keeps cancellation primary and records failed final cleanup without retrying it", async () => {
+  const controller = new AbortController();
+  const abortReason = { source: "test", stage: "final-detach" };
+  let closes = 0;
+  const service = new FridaInstrumentationService(
+    createProvider({
+      async loadScript() {
+        return { ok: true, value: createScriptObservation() };
+      },
+      async closeSession() {
+        closes += 1;
+        controller.abort(abortReason);
+        return {
+          ok: false,
+          error: new AnalysisCapabilityUnavailableError(
+            "frida",
+            "close_frida_session",
+            "detach acknowledgement failed",
+            {
+              cleanup: {
+                reason: "session remains owned",
+                resources: [createSession().sessionId],
+              },
+            },
+          ),
+        };
+      },
+    }),
+  );
+
+  const result = await service.instrument(
+    {
+      mode: "spawn",
+      deviceId: "local",
+      program: "/fixture",
+      source: { sourceKind: "inline", source: "send('ready')" },
+      durationMs: 0,
+    },
+    controller.signal,
+  );
+
+  expect(result.ok).toBe(false);
+  if (result.ok) return;
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(abortReason);
+  expect(result.error.cleanup).toEqual({
+    reason:
+      "Provider frida cannot execute close_frida_session: detach acknowledgement failed",
+    resources: [createSession().sessionId],
+  });
+  expect(result.error.partialObservation).toMatchObject({
+    normalized_result: {
+      cleanup_error:
+        "Provider frida cannot execute close_frida_session: detach acknowledgement failed",
+      instrumentation_cleanup: "incomplete_or_unknown",
+    },
+  });
+  expect(closes).toBe(1);
+});
+
+it("retains a spawned resume reported after detach when remote cleanup fails", async () => {
+  const controller = new AbortController();
+  const abortReason = new Error("cancelled during remote cleanup");
+  let statusReads = 0;
+  let closes = 0;
+  const service = new FridaInstrumentationService(
+    createProvider({
+      status() {
+        statusReads += 1;
+        return {
+          ...createSession(),
+          state: statusReads === 1 ? "paused" : "detached",
+          targetResumeObserved: statusReads > 1,
+          scripts: [],
+          messages: [],
+          messagesTruncated: false,
+        };
+      },
+      async closeSession() {
+        closes += 1;
+        controller.abort(abortReason);
+        return {
+          ok: false,
+          error: new AnalysisCapabilityUnavailableError(
+            "frida",
+            "close_frida_session",
+            "remote removal failed after detach",
+          ),
+        };
+      },
+    }),
+  );
+
+  const result = await service.instrument(
+    {
+      mode: "spawn",
+      deviceId: "local",
+      program: "/fixture",
+      source: { sourceKind: "inline", source: "send('ready')" },
+      durationMs: 0,
+    },
+    controller.signal,
+  );
+
+  expect(result.ok).toBe(false);
+  if (result.ok) return;
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(abortReason);
+  expect(result.error.partialObservation).toMatchObject({
+    normalized_result: {
+      target_state_before_cleanup: "paused",
+      target_resume_observed: true,
+      cleanup_error:
+        "Provider frida cannot execute close_frida_session: remote removal failed after detach",
+      instrumentation_cleanup: "incomplete_or_unknown",
+    },
+  });
+  expect(statusReads).toBe(2);
+  expect(closes).toBe(1);
+});
+
 it.each([
-  { cleanupState: "running" as const, resumeObserved: true },
+  { cleanupState: "running" as const, resumeObserved: false },
   { cleanupState: "paused" as const, resumeObserved: false },
+  { cleanupState: "detached" as const, resumeObserved: true },
 ])(
-  "uses a spawned target state transition after failed cleanup ($cleanupState)",
+  "uses explicit resume evidence after failed cleanup ($cleanupState)",
   async ({ cleanupState, resumeObserved }) => {
     const controller = new AbortController();
     let statusCalls = 0;
@@ -387,7 +562,7 @@ it.each([
           return {
             ...createSession(),
             state: statusCalls === 1 ? "paused" : cleanupState,
-            targetResumeObserved: false,
+            targetResumeObserved: statusCalls > 1 && resumeObserved,
             scripts: [],
             messages: [],
             messagesTruncated: false,
@@ -612,9 +787,14 @@ it("retains a cancelled provider load's source and messages in one-shot Evidence
   });
 });
 
-it.each([false, true])(
-  "keeps an ordinary provider load failure primary when cancellation is already signaled before cleanup (cleanupFails=%s)",
-  async (cleanupFails) => {
+it.each([
+  ["before cleanup", false],
+  ["before cleanup", true],
+  ["during cleanup", false],
+  ["during cleanup", true],
+] as const)(
+  "keeps an ordinary provider load failure primary when cancellation arrives %s (cleanupFails=%s)",
+  async (abortTiming, cleanupFails) => {
     const controller = new AbortController();
     const abortReason = new Error("late caller cancellation");
     const primary = new AnalysisCapabilityUnavailableError(
@@ -627,11 +807,12 @@ it.each([false, true])(
     const service = new FridaInstrumentationService(
       createProvider({
         async loadScript() {
-          controller.abort(abortReason);
+          if (abortTiming === "before cleanup") controller.abort(abortReason);
           return { ok: false, error: primary };
         },
         async closeSession() {
           closes += 1;
+          if (abortTiming === "during cleanup") controller.abort(abortReason);
           return cleanupFails
             ? {
                 ok: false,
diff --git a/src/application/frida/FridaInstrumentationService.ts b/src/application/frida/FridaInstrumentationService.ts
index b373dc2499..a8dae5fc82 100644
--- a/src/application/frida/FridaInstrumentationService.ts
+++ b/src/application/frida/FridaInstrumentationService.ts
@@ -32,6 +32,19 @@ type DeviceListOutput = z.output<
 type ProcessListOutput = z.output<
   ReturnType<typeof toolContract<"list_frida_processes">>["outputSchema"]
 >;
+type FridaSessionCloseResult = Awaited<
+  ReturnType<FridaInstrumentationPort["closeSession"]>
+>;
+type FridaSessionCancellation = {
+  readonly operation: string;
+  readonly input: StartFridaSessionInput;
+  readonly cause: unknown;
+  readonly diagnostics?: AnalysisError["diagnostics"];
+  readonly observation: FridaSessionStatus;
+  readonly closed: FridaSessionCloseResult;
+  readonly statusAfterCleanup: FridaSessionStatus | undefined;
+  readonly script: FridaScriptObservation | undefined;
+};
 
 const unreadableScriptFile = async (
   source: FridaScriptSource,
@@ -170,41 +183,16 @@ export class FridaInstrumentationService {
     };
     const closed = await this.#provider.closeSession(session.sessionId);
     const statusAfterCleanup = this.#provider.status(session.sessionId);
-    const partialObservation = fridaEvidence(
-      operation,
-      {
-        ...sessionStatusOutput(observation),
-        ...(loaded === undefined ? {} : sourceOutput(loaded)),
-        cleanup_error: closed.ok ? null : closed.error.message,
-        target_state_before_cleanup: observation.state,
-        target_resume_observed:
-          observation.targetResumeObserved ||
-          (observation.mode === "spawn" && observation.state === "running") ||
-          (closed.ok && closed.value.targetResumeObserved) ||
-          (observation.mode === "spawn" &&
-            observation.state !== "running" &&
-            statusAfterCleanup?.state === "running"),
-        instrumentation_cleanup: closed.ok
-          ? "released"
-          : "incomplete_or_unknown",
-        target_liveness_after_cleanup: "unknown",
-      },
-      fridaParameters(session.sessionId, input, session.deviceId),
-      loaded,
-    );
     return err(
-      new AnalysisCancelledError(operation, {
-        ...(cause === undefined ? {} : { cause }),
+      cancelledFridaSession({
+        operation,
+        input,
+        cause,
         diagnostics: load?.diagnostics,
-        partialObservation,
-        ...(closed.ok
-          ? {}
-          : {
-              cleanup: {
-                reason: closed.error.message,
-                resources: [session.sessionId],
-              },
-            }),
+        observation,
+        closed,
+        statusAfterCleanup,
+        script: loaded,
       }),
     );
   }
@@ -377,6 +365,18 @@ export class FridaInstrumentationService {
     };
     const closed = await this.#provider.closeSession(started.value.sessionId);
     const cleanupError = closed.ok ? null : closed.error.message;
+    if (signal?.aborted)
+      return err(
+        cancelledFridaSession({
+          operation: "instrument_with_frida",
+          input,
+          cause: signal.reason,
+          observation,
+          closed,
+          statusAfterCleanup: this.#provider.status(started.value.sessionId),
+          script: loaded.value,
+        }),
+      );
     const evidence = fridaEvidence(
       "instrument_with_frida",
       {
@@ -442,6 +442,50 @@ const fridaEvidence = (
     },
   );
 
+const cancelledFridaSession = ({
+  operation,
+  input,
+  cause,
+  diagnostics,
+  observation,
+  closed,
+  statusAfterCleanup,
+  script,
+}: FridaSessionCancellation): AnalysisCancelledError => {
+  const cleanupError = closed.ok ? null : closed.error.message;
+  return new AnalysisCancelledError(operation, {
+    ...(cause === undefined ? {} : { cause }),
+    diagnostics,
+    partialObservation: fridaEvidence(
+      operation,
+      {
+        ...sessionStatusOutput(observation),
+        ...(script === undefined ? {} : sourceOutput(script)),
+        cleanup_error: cleanupError,
+        target_state_before_cleanup: observation.state,
+        target_resume_observed:
+          observation.targetResumeObserved ||
+          (closed.ok && closed.value.targetResumeObserved) ||
+          statusAfterCleanup?.targetResumeObserved === true,
+        instrumentation_cleanup: closed.ok
+          ? "released"
+          : "incomplete_or_unknown",
+        target_liveness_after_cleanup: "unknown",
+      },
+      fridaParameters(observation.sessionId, input, observation.deviceId),
+      script,
+    ),
+    ...(closed.ok
+      ? {}
+      : {
+          cleanup: {
+            reason: closed.error.message,
+            resources: [observation.sessionId],
+          },
+        }),
+  });
+};
+
 const fridaParameters = (
   sessionId: string,
   input: StartFridaSessionInput,
diff --git a/tests/boundary/mcp/fridaLifecycleMcp.test.ts b/tests/boundary/mcp/fridaLifecycleMcp.test.ts
index 2c27ef9897..ec9d03a83a 100644
--- a/tests/boundary/mcp/fridaLifecycleMcp.test.ts
+++ b/tests/boundary/mcp/fridaLifecycleMcp.test.ts
@@ -12,7 +12,7 @@ import type {
   Script,
   Session,
 } from "frida";
-import { expect, it, onTestFinished } from "vitest";
+import { expect, it, onTestFinished, vi } from "vitest";
 
 import { FridaScriptLoadCancelledError } from "../../../src/application/frida/FridaInstrumentationPort.js";
 import type {
@@ -35,7 +35,10 @@ import { silentLogger } from "../../../src/logger.js";
 import { createServer } from "../../../src/server/createServer.js";
 import { EvidenceMcpServer } from "../../../src/server/EvidenceMcpServer.js";
 import { registerFridaTools } from "../../../src/server/registerFridaTools.js";
-import { createToolResultDelivery } from "../../../src/server/toolResult.js";
+import {
+  createToolResultDelivery,
+  ToolResultDelivery,
+} from "../../../src/server/toolResult.js";
 import { createTestBinarySession } from "../../fixtures/binarySession.js";
 import { parseMcpToolError } from "../../fixtures/mcpToolError.js";
 
@@ -69,6 +72,7 @@ const nativeFixture = () => {
     create: async () => {},
     load: async () => {},
     resume: async () => {},
+    detach: async () => {},
     afterLoad: () => {},
     discover: async () => {},
     unloadFailures: 0,
@@ -98,6 +102,7 @@ const nativeFixture = () => {
     isDetached: () => detached,
     async detach() {
       controls.detachCalls += 1;
+      await controls.detach();
       if (controls.detachFailures > 0) {
         controls.detachFailures -= 1;
         throw new Error("transient detach failure");
@@ -327,6 +332,130 @@ it("retains detached state and resume evidence when remote cleanup needs retry",
   expect(fixture.controls.remoteRemovals).toBe(2);
 });
 
+it.each([
+  { cancel: false, detachFails: false },
+  { cancel: true, detachFails: false },
+  { cancel: false, detachFails: true },
+  { cancel: true, detachFails: true },
+])(
+  "classifies server completion after final detach (cancel=$cancel, detachFails=$detachFails)",
+  async ({ cancel, detachFails }) => {
+    const fixture = await connectedFixture();
+    const held = gate();
+    onTestFinished(held.release);
+    fixture.controls.detach = held.wait;
+    fixture.controls.detachFailures = detachFails ? 1 : 0;
+    let serverSignal: AbortSignal | undefined;
+    const load = fixture.manager.loadScript.bind(fixture.manager);
+    const loadSpy = vi
+      .spyOn(fixture.manager, "loadScript")
+      .mockImplementation((id, source, signal) => {
+        serverSignal = signal;
+        return load(id, source, signal);
+      });
+    const success = vi.spyOn(
+      ToolResultDelivery.prototype,
+      "toEvidenceToolResult",
+    );
+    const partial = vi.spyOn(
+      ToolResultDelivery.prototype,
+      "toRecordedPartialErrorToolResult",
+    );
+    onTestFinished(() => {
+      loadSpy.mockRestore();
+      success.mockRestore();
+      partial.mockRestore();
+    });
+    const controller = new AbortController();
+    const pending = fixture.client
+      .callTool(
+        {
+          name: "instrument_with_frida",
+          arguments: {
+            mode: "attach",
+            pid: 512,
+            device_id: "local",
+            source_kind: "inline",
+            source: "completed-before-detach",
+            duration_ms: 0,
+          },
+        },
+        { signal: controller.signal },
+      )
+      .then(
+        (value) => ({ kind: "result" as const, value }),
+        (cause: unknown) => ({ kind: "rejected" as const, cause }),
+      );
+    await held.entered;
+    expect(fixture.unloaded).toEqual(["completed-before-detach"]);
+    if (cancel) {
+      controller.abort(new Error("cancel during final detach"));
+      await fixture.client.ping();
+    }
+    expect(serverSignal?.aborted).toBe(cancel);
+    const serverReason: unknown = serverSignal?.reason;
+    held.release();
+    const result = await pending;
+    await vi.waitFor(() =>
+      expect(success.mock.calls.length + partial.mock.calls.length).toBe(1),
+    );
+    expect(fixture.controls.detachCalls).toBe(1);
+    expect(fixture.controls.resumes).toBe(0);
+    const records = fixture.session
+      .exportEvidenceBundle()
+      .records.filter((record) => record.operation === "instrument_with_frida");
+    expect(records).toHaveLength(1);
+    const evidence = records[0];
+    expect(evidence).toMatchObject({
+      normalized_result: {
+        messages: [{ type: "send", payload: "completed-before-detach" }],
+        cleanup_error: detachFails
+          ? expect.stringContaining("transient detach failure")
+          : null,
+      },
+    });
+    const sessionId = String(evidence?.parameters.session_id);
+    expect(fixture.manager.status(sessionId) !== undefined).toBe(detachFails);
+    if (cancel) {
+      expect(result.kind).toBe("rejected");
+      expect(success).not.toHaveBeenCalled();
+      const error = partial.mock.calls[0]?.[0];
+      expect(error).toBeInstanceOf(AnalysisCancelledError);
+      expect(error?.cause).toBe(serverReason);
+      if (detachFails)
+        expect(error?.cleanup).toMatchObject({ resources: [sessionId] });
+      else expect(error?.cleanup).toBeUndefined();
+      expect(error?.partialObservation).toEqual(evidence);
+      expect(evidence).toMatchObject({
+        normalized_result: {
+          instrumentation_cleanup: detachFails
+            ? "incomplete_or_unknown"
+            : "released",
+          target_state_before_cleanup: "running",
+          target_resume_observed: false,
+          target_liveness_after_cleanup: "unknown",
+        },
+      });
+    } else {
+      expect(result.kind).toBe("result");
+      if (result.kind !== "result") throw result.cause;
+      expect(result.value.isError).not.toBe(true);
+      expect(partial).not.toHaveBeenCalled();
+      expect(success).toHaveBeenCalledOnce();
+    }
+    if (detachFails) {
+      const retried = await fixture.client.callTool({
+        name: "close_frida_session",
+        arguments: { session_id: sessionId },
+      });
+      expect(retried.isError).not.toBe(true);
+      expect(fixture.controls.detachCalls).toBe(2);
+      expect(fixture.manager.status(sessionId)).toBeUndefined();
+      expect(fixture.unloaded).toEqual(["completed-before-detach"]);
+    }
+  },
+);
+
 it.each([
   ["a trailing high surrogate", "x".repeat(32_765) + "\ud800"],
   ["repeated high surrogates", "\ud800".repeat(10_922)],