diff --git a/.jscpd.json b/.jscpd.json
index a620363ba4..9c1a572ff5 100644
--- a/.jscpd.json
+++ b/.jscpd.json
@@ -1,6 +1,6 @@
 {
-  "_comment": "Test files are intentionally NOT excluded: the gate used to report zero clones because it skipped **/*.test.ts, hiding all test-tree duplication. Current actual is ~2.4% lines across src+ and tests/, down from 3.4% when tests were included. Lower this as duplication is removed.",
-  "threshold": 2.5,
+  "_comment": "Test files are intentionally NOT excluded: the gate used to report zero clones because it skipped **/*.test.ts, hiding all test-tree duplication. Current actual is ~2.47% lines across src+ and tests/, down from 3.4% when tests were included. The 2.6% limit leaves modest headroom for ordinary changes; lower it as duplication is removed.",
+  "threshold": 2.6,
   "reporters": ["consoleFull"],
   "ignore": [
     "node_modules/**",
diff --git a/tests/boundary/process/javascriptRuntimeReconciliationAmbiguity.test.ts b/tests/boundary/process/javascriptRuntimeReconciliationAmbiguity.test.ts
index 58b12ea3e7..3604b862ad 100644
--- a/tests/boundary/process/javascriptRuntimeReconciliationAmbiguity.test.ts
+++ b/tests/boundary/process/javascriptRuntimeReconciliationAmbiguity.test.ts
@@ -7,15 +7,18 @@ import { afterEach, expect, it } from "vitest";
 
 import { createTestTempDirectory } from "../../fixtures/temporaryDirectory.js";
 
-import { createElectronEvidence } from "../../../src/application/javascript/ElectronEvidence.js";
-import { analyzeJavaScriptApplication } from "../../support/javascriptApplicationScope.js";
 import {
   parseRuntimeReconciliationInput,
   reconcileJavaScriptRuntime,
 } from "../../../src/domain/javascript/javascriptRuntimeReconciliation.js";
 import { reconcileJavaScriptRuntimeInputSchema } from "../../../src/domain/javascript/javascriptRuntimeReconciliationSchemas.js";
-import { inspectElectronPageInputSchema } from "../../../src/domain/javascript/electronObservation.js";
-import { createWebTextArtifact } from "../../../src/domain/webContentArtifact.js";
+
+import {
+  SOURCE,
+  applicationFixture,
+  analyzeFixture,
+  electronRuntimeEvidence,
+} from "../../fixtures/javascriptRuntimeReconciliation.js";
 
 const reconcileInput = (input: unknown) =>
   reconcileJavaScriptRuntime(
@@ -24,7 +27,6 @@ const reconcileInput = (input: unknown) =>
     ),
   );
 
-const SOURCE = `const worker = new Worker("./worker.js");\nexport const observed = worker;\n`;
 const execute = promisify(execFile);
 
 const temporary: string[] = [];
@@ -194,151 +196,3 @@ it("runs the local verifier from operator-provided paths without emitting source
   });
   expect(stdout).not.toContain(SOURCE.trim());
 }, 10_000);
-
-const applicationFixture = async (): Promise<string> => {
-  const root = await createTestTempDirectory("rea-runtime-reconciliation-");
-  await Promise.all([
-    writeFile(
-      join(root, "package.json"),
-      JSON.stringify({
-        name: "rea-runtime-reconciliation-fixture",
-        version: "1.0.0",
-        renderer: "index.html",
-      }),
-    ),
-    writeFile(join(root, "index.html"), "<script src='./app.js'></script>"),
-    writeFile(join(root, "app.js"), SOURCE),
-    writeFile(join(root, "worker.js"), "self.onmessage = () => undefined;\n"),
-  ]);
-  return root;
-};
-
-const analyzeFixture = async (root: string) => {
-  const result = await analyzeJavaScriptApplication({
-    input_path: root,
-  });
-  if (!result.ok) throw result.error;
-  return result.value;
-};
-
-const electronRuntimeEvidence = (
-  root: string,
-  source: string,
-  options: {
-    readonly scriptFile?: string;
-    readonly includeWorker?: boolean;
-    readonly targetId?: string;
-    readonly sourceIncluded?: boolean;
-    readonly workersUnavailable?: boolean;
-  } = {},
-) => {
-  const scriptFile = options.scriptFile ?? "app.js";
-  const includeWorker = options.includeWorker ?? true;
-  const targetId = options.targetId ?? "target-main";
-  const sourceIncluded = options.sourceIncluded ?? true;
-  const input = inspectElectronPageInputSchema.parse({
-    cdp_endpoint: "http://127.0.0.1:9223",
-    target_id: targetId,
-    observation_ms: 100,
-    include_script_sources: sourceIncluded,
-  });
-  return createElectronEvidence(
-    "inspect_electron_page",
-    input,
-    {
-      browser: {
-        product: "Electron/fixture",
-        protocol_version: "1.3",
-        revision: "fixture",
-        user_agent: "Electron fixture",
-        js_version: "13",
-      },
-      target: {
-        target_id: targetId,
-        type: "page",
-        title: "Fixture",
-        file_path: join(root, "index.html"),
-        attached: false,
-      },
-      capture_window: {
-        started_at: "2026-07-15T00:00:00.000Z",
-        ended_at: "2026-07-15T00:00:00.100Z",
-        observation_ms: 100,
-      },
-      completeness: options.workersUnavailable
-        ? {
-            ...completeCapture(),
-            status: "attach_limited" as const,
-            conditions: ["attach_limited" as const],
-            attach_limited_sections: ["workers" as const],
-            unavailable_sections: ["workers" as const],
-          }
-        : completeCapture(),
-      frames: [
-        {
-          frame_id: "frame-main",
-          parent_frame_id: null,
-          file_path: join(root, "index.html"),
-        },
-      ],
-      dom: { total_nodes: 0, nodes: [] },
-      scripts: {
-        total: 1,
-        items: [
-          {
-            script_key: `electron_script_${"1".repeat(64)}`,
-            frame_id: "frame-main",
-            file_path: join(root, scriptFile),
-            cdp_hash: "fixture",
-            length: Buffer.byteLength(source),
-            is_module: true,
-            language: "JavaScript",
-            source: {
-              included: true as const,
-              artifact: createWebTextArtifact(source, "text/javascript"),
-            },
-          },
-        ],
-      },
-      resources: [],
-      workers: includeWorker
-        ? [
-            {
-              target_id: "worker-main",
-              type: "worker",
-              file_path: join(root, "worker.js"),
-              attached: false,
-              opener_target_id: targetId,
-              parent_frame_id: "frame-main",
-            },
-          ]
-        : [],
-      limitations: ["Synthetic passive capture fixture."],
-    },
-    {
-      id: "rea-cdp-electron",
-      name: "REA Electron file-page CDP observation provider",
-      version: "1",
-    },
-  );
-};
-
-const completeCapture = () => ({
-  status: "complete_within_window" as const,
-  conditions: ["complete_within_window" as const],
-  policy_filtered_sections: [],
-  attach_limited_sections: [],
-  truncated_sections: [],
-  unavailable_sections: [],
-  excluded: [],
-  dropped_events: {
-    scripts: 0,
-    network_requests: 0,
-    console_events: 0,
-    websocket_connections: 0,
-    websocket_frames: 0,
-    webmcp_tools: 0,
-    timeline_events: 0,
-    total: 0,
-  },
-});
diff --git a/tests/composition/runtime-observation/javascriptRuntimeReconciliation.test.ts b/tests/composition/runtime-observation/javascriptRuntimeReconciliation.test.ts
index e69e1f486e..5d9eab69b0 100644
--- a/tests/composition/runtime-observation/javascriptRuntimeReconciliation.test.ts
+++ b/tests/composition/runtime-observation/javascriptRuntimeReconciliation.test.ts
@@ -5,9 +5,7 @@ import { expect, it } from "vitest";
 
 import { createTestTempDirectory } from "../../fixtures/temporaryDirectory.js";
 
-import { createElectronEvidence } from "../../../src/application/javascript/ElectronEvidence.js";
 import { createElectronActiveEvidence } from "../../../src/application/javascript/ElectronActiveEvidence.js";
-import { analyzeJavaScriptApplication } from "../../support/javascriptApplicationScope.js";
 import { reconcileJavaScriptRuntimeEvidence } from "../../../src/application/javascript/JavaScriptRuntimeReconciliationService.js";
 import { createEvidence } from "../../../src/domain/evidence.js";
 import {
@@ -17,10 +15,15 @@ import {
 import { reconcileJavaScriptRuntimeInputSchema } from "../../../src/domain/javascript/javascriptRuntimeReconciliationSchemas.js";
 import { javascriptRuntimeReconciliationResultSchema } from "../../../src/domain/javascript/javascriptRuntimeReconciliationSchemas.js";
 import { electronActiveObservationInputSchema } from "../../../src/domain/javascript/electronActiveObservation.js";
-import { inspectElectronPageInputSchema } from "../../../src/domain/javascript/electronObservation.js";
-import { createWebTextArtifact } from "../../../src/domain/webContentArtifact.js";
 import { createElectronActiveObservationFixtureResult } from "../../../src/domain/javascript/electronActiveObservation.fixture.js";
 
+import {
+  SOURCE,
+  applicationFixture,
+  analyzeFixture,
+  electronRuntimeEvidence,
+} from "../../fixtures/javascriptRuntimeReconciliation.js";
+
 const reconcileInput = (input: unknown) =>
   reconcileJavaScriptRuntime(
     parseRuntimeReconciliationInput(
@@ -28,8 +31,6 @@ const reconcileInput = (input: unknown) =>
     ),
   );
 
-const SOURCE = `const worker = new Worker("./worker.js");\nexport const observed = worker;\n`;
-
 it("preserves source-capture input paths for runtime Evidence", async () => {
   const root = await applicationFixture();
   const application = await analyzeFixture(root);
@@ -418,162 +419,3 @@ it("imports an operator-provided cache layer through an explicit file mapping",
     sharedFile?.observations.map(({ properties }) => properties.path),
   ).toEqual(expect.arrayContaining(["app.js", "mapped/chunk.js"]));
 });
-
-const applicationFixture = async (): Promise<string> => {
-  const root = await createTestTempDirectory("rea-runtime-reconciliation-");
-  await Promise.all([
-    writeFile(
-      join(root, "package.json"),
-      JSON.stringify({
-        name: "rea-runtime-reconciliation-fixture",
-        version: "1.0.0",
-        renderer: "index.html",
-      }),
-    ),
-    writeFile(join(root, "index.html"), "<script src='./app.js'></script>"),
-    writeFile(join(root, "app.js"), SOURCE),
-    writeFile(join(root, "worker.js"), "self.onmessage = () => undefined;\n"),
-  ]);
-  return root;
-};
-
-const analyzeFixture = async (root: string) => {
-  const result = await analyzeJavaScriptApplication({
-    input_path: root,
-  });
-  if (!result.ok) throw result.error;
-  return result.value;
-};
-
-const electronRuntimeEvidence = (
-  root: string,
-  source: string,
-  options: {
-    readonly scriptFile?: string;
-    readonly includeWorker?: boolean;
-    readonly targetId?: string;
-    readonly sourceIncluded?: boolean;
-    readonly workersUnavailable?: boolean;
-    readonly scriptsUnavailable?: boolean;
-  } = {},
-) => {
-  const scriptFile = options.scriptFile ?? "app.js";
-  const includeWorker = options.includeWorker ?? true;
-  const targetId = options.targetId ?? "target-main";
-  const sourceIncluded = options.sourceIncluded ?? true;
-  const input = inspectElectronPageInputSchema.parse({
-    cdp_endpoint: "http://127.0.0.1:9223",
-    target_id: targetId,
-    observation_ms: 100,
-    include_script_sources: sourceIncluded,
-  });
-  return createElectronEvidence(
-    "inspect_electron_page",
-    input,
-    {
-      browser: {
-        product: "Electron/fixture",
-        protocol_version: "1.3",
-        revision: "fixture",
-        user_agent: "Electron fixture",
-        js_version: "13",
-      },
-      target: {
-        target_id: targetId,
-        type: "page",
-        title: "Fixture",
-        file_path: join(root, "index.html"),
-        attached: false,
-      },
-      capture_window: {
-        started_at: "2026-07-15T00:00:00.000Z",
-        ended_at: "2026-07-15T00:00:00.100Z",
-        observation_ms: 100,
-      },
-      completeness: captureCompleteness(options),
-      frames: [
-        {
-          frame_id: "frame-main",
-          parent_frame_id: null,
-          file_path: join(root, "index.html"),
-        },
-      ],
-      dom: { total_nodes: 0, nodes: [] },
-      scripts: {
-        total: 1,
-        items: [
-          {
-            script_key: `electron_script_${"1".repeat(64)}`,
-            frame_id: "frame-main",
-            file_path: join(root, scriptFile),
-            cdp_hash: "fixture",
-            length: Buffer.byteLength(source),
-            is_module: true,
-            language: "JavaScript",
-            source: {
-              included: true as const,
-              artifact: createWebTextArtifact(source, "text/javascript"),
-            },
-          },
-        ],
-      },
-      resources: [],
-      workers: includeWorker
-        ? [
-            {
-              target_id: "worker-main",
-              type: "worker",
-              file_path: join(root, "worker.js"),
-              attached: false,
-              opener_target_id: targetId,
-              parent_frame_id: "frame-main",
-            },
-          ]
-        : [],
-      limitations: ["Synthetic passive capture fixture."],
-    },
-    {
-      id: "rea-cdp-electron",
-      name: "REA Electron file-page CDP observation provider",
-      version: "1",
-    },
-  );
-};
-
-const completeCapture = () => ({
-  status: "complete_within_window" as const,
-  conditions: ["complete_within_window" as const],
-  policy_filtered_sections: [],
-  attach_limited_sections: [],
-  truncated_sections: [],
-  unavailable_sections: [],
-  excluded: [],
-  dropped_events: {
-    scripts: 0,
-    network_requests: 0,
-    console_events: 0,
-    websocket_connections: 0,
-    websocket_frames: 0,
-    webmcp_tools: 0,
-    timeline_events: 0,
-    total: 0,
-  },
-});
-
-const captureCompleteness = (options: {
-  readonly workersUnavailable?: boolean;
-  readonly scriptsUnavailable?: boolean;
-}) => {
-  const unavailableSections = [
-    ...(options.scriptsUnavailable ? (["scripts"] as const) : []),
-    ...(options.workersUnavailable ? (["workers"] as const) : []),
-  ];
-  if (unavailableSections.length === 0) return completeCapture();
-  return {
-    ...completeCapture(),
-    status: "attach_limited" as const,
-    conditions: ["attach_limited" as const],
-    attach_limited_sections: unavailableSections,
-    unavailable_sections: unavailableSections,
-  };
-};
diff --git a/tests/fixtures/javascriptRuntimeReconciliation.ts b/tests/fixtures/javascriptRuntimeReconciliation.ts
new file mode 100644
index 0000000000..baca10aeb6
--- /dev/null
+++ b/tests/fixtures/javascriptRuntimeReconciliation.ts
@@ -0,0 +1,169 @@
+import { writeFile } from "node:fs/promises";
+import { join } from "node:path";
+
+import { createElectronEvidence } from "../../src/application/javascript/ElectronEvidence.js";
+import { inspectElectronPageInputSchema } from "../../src/domain/javascript/electronObservation.js";
+import { createWebTextArtifact } from "../../src/domain/webContentArtifact.js";
+import { analyzeJavaScriptApplication } from "../support/javascriptApplicationScope.js";
+import { createTestTempDirectory } from "./temporaryDirectory.js";
+
+export const SOURCE = `const worker = new Worker("./worker.js");\nexport const observed = worker;\n`;
+
+export const applicationFixture = async (): Promise<string> => {
+  const root = await createTestTempDirectory("rea-runtime-reconciliation-");
+  await Promise.all([
+    writeFile(
+      join(root, "package.json"),
+      JSON.stringify({
+        name: "rea-runtime-reconciliation-fixture",
+        version: "1.0.0",
+        renderer: "index.html",
+      }),
+    ),
+    writeFile(join(root, "index.html"), "<script src='./app.js'></script>"),
+    writeFile(join(root, "app.js"), SOURCE),
+    writeFile(join(root, "worker.js"), "self.onmessage = () => undefined;\n"),
+  ]);
+  return root;
+};
+
+export const analyzeFixture = async (root: string) => {
+  const result = await analyzeJavaScriptApplication({
+    input_path: root,
+  });
+  if (!result.ok) throw result.error;
+  return result.value;
+};
+
+export const electronRuntimeEvidence = (
+  root: string,
+  source: string,
+  options: {
+    readonly scriptFile?: string;
+    readonly includeWorker?: boolean;
+    readonly targetId?: string;
+    readonly sourceIncluded?: boolean;
+    readonly workersUnavailable?: boolean;
+    readonly scriptsUnavailable?: boolean;
+  } = {},
+) => {
+  const scriptFile = options.scriptFile ?? "app.js";
+  const includeWorker = options.includeWorker ?? true;
+  const targetId = options.targetId ?? "target-main";
+  const sourceIncluded = options.sourceIncluded ?? true;
+  const input = inspectElectronPageInputSchema.parse({
+    cdp_endpoint: "http://127.0.0.1:9223",
+    target_id: targetId,
+    observation_ms: 100,
+    include_script_sources: sourceIncluded,
+  });
+  return createElectronEvidence(
+    "inspect_electron_page",
+    input,
+    {
+      browser: {
+        product: "Electron/fixture",
+        protocol_version: "1.3",
+        revision: "fixture",
+        user_agent: "Electron fixture",
+        js_version: "13",
+      },
+      target: {
+        target_id: targetId,
+        type: "page",
+        title: "Fixture",
+        file_path: join(root, "index.html"),
+        attached: false,
+      },
+      capture_window: {
+        started_at: "2026-07-15T00:00:00.000Z",
+        ended_at: "2026-07-15T00:00:00.100Z",
+        observation_ms: 100,
+      },
+      completeness: captureCompleteness(options),
+      frames: [
+        {
+          frame_id: "frame-main",
+          parent_frame_id: null,
+          file_path: join(root, "index.html"),
+        },
+      ],
+      dom: { total_nodes: 0, nodes: [] },
+      scripts: {
+        total: 1,
+        items: [
+          {
+            script_key: `electron_script_${"1".repeat(64)}`,
+            frame_id: "frame-main",
+            file_path: join(root, scriptFile),
+            cdp_hash: "fixture",
+            length: Buffer.byteLength(source),
+            is_module: true,
+            language: "JavaScript",
+            source: {
+              included: true as const,
+              artifact: createWebTextArtifact(source, "text/javascript"),
+            },
+          },
+        ],
+      },
+      resources: [],
+      workers: includeWorker
+        ? [
+            {
+              target_id: "worker-main",
+              type: "worker",
+              file_path: join(root, "worker.js"),
+              attached: false,
+              opener_target_id: targetId,
+              parent_frame_id: "frame-main",
+            },
+          ]
+        : [],
+      limitations: ["Synthetic passive capture fixture."],
+    },
+    {
+      id: "rea-cdp-electron",
+      name: "REA Electron file-page CDP observation provider",
+      version: "1",
+    },
+  );
+};
+
+const completeCapture = () => ({
+  status: "complete_within_window" as const,
+  conditions: ["complete_within_window" as const],
+  policy_filtered_sections: [],
+  attach_limited_sections: [],
+  truncated_sections: [],
+  unavailable_sections: [],
+  excluded: [],
+  dropped_events: {
+    scripts: 0,
+    network_requests: 0,
+    console_events: 0,
+    websocket_connections: 0,
+    websocket_frames: 0,
+    webmcp_tools: 0,
+    timeline_events: 0,
+    total: 0,
+  },
+});
+
+const captureCompleteness = (options: {
+  readonly workersUnavailable?: boolean;
+  readonly scriptsUnavailable?: boolean;
+}) => {
+  const unavailableSections = [
+    ...(options.scriptsUnavailable ? (["scripts"] as const) : []),
+    ...(options.workersUnavailable ? (["workers"] as const) : []),
+  ];
+  if (unavailableSections.length === 0) return completeCapture();
+  return {
+    ...completeCapture(),
+    status: "attach_limited" as const,
+    conditions: ["attach_limited" as const],
+    attach_limited_sections: unavailableSections,
+    unavailable_sections: unavailableSections,
+  };
+};