diff --git a/src/application/binaryDiagnostics/AppleIpsService.test.ts b/src/application/binaryDiagnostics/AppleIpsService.test.ts
index 894e045b52..1784b7dc70 100644
--- a/src/application/binaryDiagnostics/AppleIpsService.test.ts
+++ b/src/application/binaryDiagnostics/AppleIpsService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { expect, it } from "vitest";
 import { AppleIpsService } from "./AppleIpsService.js";
 import { APPLE_IPS_PROVIDER } from "../../domain/investigationProviders.js";
@@ -232,12 +233,13 @@ it.each([
   },
 );
 
-it("discards an observation if the caller cancels while the provider completes", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late AppleIps cancellation" };
   const service = new AppleIpsService({
     identity,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report));
     },
   });
@@ -245,8 +247,13 @@ it("discards an observation if the caller cancels while the provider completes",
     { path: report.artifact.path },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_apple_ips",
+    normalized_result: report,
+  });
 });
 
 it.each([
diff --git a/src/application/binaryDiagnostics/DevicetreeService.test.ts b/src/application/binaryDiagnostics/DevicetreeService.test.ts
index 51b9d11fde..6fe7da18eb 100644
--- a/src/application/binaryDiagnostics/DevicetreeService.test.ts
+++ b/src/application/binaryDiagnostics/DevicetreeService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { expect, it } from "vitest";
 import { DevicetreeService } from "./DevicetreeService.js";
 import { DEVICETREE_PROVIDER } from "../../domain/investigationProviders.js";
@@ -72,12 +73,13 @@ it("validates caller paths before invoking the provider", async () => {
   if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisInputError);
   expect(calls).toBe(0);
 });
-it("rejects cancellation at provider completion", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late Devicetree cancellation" };
   const service = new DevicetreeService({
     identity: DEVICETREE_PROVIDER,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report()));
     },
   });
@@ -85,8 +87,13 @@ it("rejects cancellation at provider completion", async () => {
     { path: "/board.dtb" },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_devicetree",
+    normalized_result: report(),
+  });
 });
 it("rejects provider coverage and source-range inconsistencies", async () => {
   for (const change of [
diff --git a/src/application/binaryDiagnostics/ElfNotesService.test.ts b/src/application/binaryDiagnostics/ElfNotesService.test.ts
index 75547fc619..f71883719e 100644
--- a/src/application/binaryDiagnostics/ElfNotesService.test.ts
+++ b/src/application/binaryDiagnostics/ElfNotesService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { expect, it } from "vitest";
 import { ElfNotesService } from "./ElfNotesService.js";
 import { ELF_NOTES_PROVIDER } from "../../domain/investigationProviders.js";
@@ -106,12 +107,13 @@ it("retains an examined empty table and rejects an uncounted table", async () =>
   }
 });
 
-it("discards an observation if the caller cancels while the provider completes", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late ElfNotes cancellation" };
   const service = new ElfNotesService({
     identity,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report));
     },
   });
@@ -119,6 +121,11 @@ it("discards an observation if the caller cancels while the provider completes",
     { path: report.artifact.path },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_elf_notes",
+    normalized_result: report,
+  });
 });
diff --git a/src/application/binaryDiagnostics/ElfUnwindRangesService.test.ts b/src/application/binaryDiagnostics/ElfUnwindRangesService.test.ts
index 88ce45ca43..422233a1a4 100644
--- a/src/application/binaryDiagnostics/ElfUnwindRangesService.test.ts
+++ b/src/application/binaryDiagnostics/ElfUnwindRangesService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { expect, it } from "vitest";
 import { ElfUnwindRangesService } from "./ElfUnwindRangesService.js";
 import { ELF_UNWIND_RANGES_PROVIDER } from "../../domain/investigationProviders.js";
@@ -406,12 +407,13 @@ it("rejects a report that fails the output schema", async () => {
   if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisOutputError);
 });
 
-it("discards an observation if the caller cancels while the provider completes", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late ElfUnwindRanges cancellation" };
   const service = new ElfUnwindRangesService({
     identity,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report));
     },
   });
@@ -419,6 +421,11 @@ it("discards an observation if the caller cancels while the provider completes",
     { path: report.artifact.path },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_elf_unwind_ranges",
+    normalized_result: report,
+  });
 });
diff --git a/src/application/binaryDiagnostics/NativeInitializersService.test.ts b/src/application/binaryDiagnostics/NativeInitializersService.test.ts
index e0d836b181..c01de60fb0 100644
--- a/src/application/binaryDiagnostics/NativeInitializersService.test.ts
+++ b/src/application/binaryDiagnostics/NativeInitializersService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { expect, it } from "vitest";
 import { NativeInitializersService } from "./NativeInitializersService.js";
 import { NATIVE_INITIALIZERS_PROVIDER } from "../../domain/investigationProviders.js";
@@ -113,12 +114,13 @@ it("rejects a slot offset outside the artifact", async () => {
   if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisOutputError);
 });
 
-it("discards an observation if the caller cancels while the provider completes", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late NativeInitializers cancellation" };
   const service = new NativeInitializersService({
     identity,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report));
     },
   });
@@ -126,6 +128,11 @@ it("discards an observation if the caller cancels while the provider completes",
     { path: report.artifact.path },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_native_initializers",
+    normalized_result: report,
+  });
 });
diff --git a/src/application/binaryDiagnostics/PeCertificatesService.test.ts b/src/application/binaryDiagnostics/PeCertificatesService.test.ts
index 5fb1b34213..fa73b22f77 100644
--- a/src/application/binaryDiagnostics/PeCertificatesService.test.ts
+++ b/src/application/binaryDiagnostics/PeCertificatesService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { createHash } from "node:crypto";
 import { inspectPeCertificatesInputSchema } from "../../domain/native/peCertificates.js";
 import { peCertificateFixture } from "../../native/pe/PeCertificates.fixture.js";
@@ -49,12 +50,13 @@ it("rejects a relative path and extra arguments before reading", async () => {
   expect(calls).toBe(0);
 });
 
-it("discards an observation if the caller cancels while the provider completes", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late PeCertificates cancellation" };
   const service = new PeCertificatesService({
     identity,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report));
     },
   });
@@ -62,8 +64,13 @@ it("discards an observation if the caller cancels while the provider completes",
     { path: report.artifact.path },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_pe_certificates",
+    normalized_result: report,
+  });
 });
 
 it("retains complete certificate provenance from the production parser", async () => {
diff --git a/src/application/binaryDiagnostics/PeImportsService.test.ts b/src/application/binaryDiagnostics/PeImportsService.test.ts
index 58a342bbd5..c641bf5385 100644
--- a/src/application/binaryDiagnostics/PeImportsService.test.ts
+++ b/src/application/binaryDiagnostics/PeImportsService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { expect, it } from "vitest";
 import { PeImportsService } from "./PeImportsService.js";
 import { PE_IMPORTS_PROVIDER } from "../../domain/investigationProviders.js";
@@ -116,12 +117,13 @@ it.each(["import_directory", "delay_import_directory"] as const)(
   },
 );
 
-it("discards an observation if the caller cancels while the provider completes", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late PeImports cancellation" };
   const service = new PeImportsService({
     identity,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report));
     },
   });
@@ -129,8 +131,13 @@ it("discards an observation if the caller cancels while the provider completes",
     { path: report.artifact.path },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_pe_imports",
+    normalized_result: report,
+  });
 });
 
 it("publishes every consumed directory span as its own Evidence location", async () => {
diff --git a/src/application/binaryDiagnostics/WindowsShortcutService.test.ts b/src/application/binaryDiagnostics/WindowsShortcutService.test.ts
index 8deb031b33..4aa8be43bd 100644
--- a/src/application/binaryDiagnostics/WindowsShortcutService.test.ts
+++ b/src/application/binaryDiagnostics/WindowsShortcutService.test.ts
@@ -1,3 +1,4 @@
+import { parseEvidence } from "../../domain/evidence.js";
 import { expect, it } from "vitest";
 import { WindowsShortcutService } from "./WindowsShortcutService.js";
 import { WINDOWS_SHORTCUT_PROVIDER } from "../../domain/investigationProviders.js";
@@ -143,12 +144,13 @@ it("rejects complete coverage that still lists issues", async () => {
   if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisOutputError);
 });
 
-it("discards an observation if the caller cancels while the provider completes", async () => {
+it("retains a completed observation when the caller cancels as the provider completes", async () => {
   const controller = new AbortController();
+  const reason = { request: "late WindowsShortcut cancellation" };
   const service = new WindowsShortcutService({
     identity,
     inspect: () => {
-      controller.abort();
+      controller.abort(reason);
       return Promise.resolve(ok(report));
     },
   });
@@ -156,6 +158,11 @@ it("discards an observation if the caller cancels while the provider completes",
     { path: report.artifact.path },
     { signal: controller.signal },
   );
-  expect(result.ok).toBe(false);
-  if (!result.ok) expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  if (result.ok) throw new Error("Expected late cancellation");
+  expect(result.error).toBeInstanceOf(AnalysisCancelledError);
+  expect(result.error.cause).toBe(reason);
+  expect(parseEvidence(result.error.partialObservation)).toMatchObject({
+    operation: "inspect_windows_shortcut",
+    normalized_result: report,
+  });
 });