diff --git a/examples/rsc-agent-runtime/src/events/tool/after.tsx b/examples/rsc-agent-runtime/src/events/tool/after.tsx
index edfb8cbac..74e5e349b 100644
--- a/examples/rsc-agent-runtime/src/events/tool/after.tsx
+++ b/examples/rsc-agent-runtime/src/events/tool/after.tsx
@@ -4,6 +4,7 @@ import { Agent } from '@agent-bundle/runtime';
 import type { AgentEventRouteProps } from 'agent-bundle';
 import * as React from 'react';
 
+import { writeEvalProbe } from '../../hook/eval-probe.js';
 import { normalizeClaudeHook, normalizeCodexHook } from '../../hook/normalize.js';
 import { createFileRuntimeKernel, resolveImplicitRuntimeStateFile } from '../../runtime/state-file.js';
 
@@ -19,34 +20,40 @@ export default async function AfterFileEdit({
   native,
   signal,
 }: AgentEventRouteProps) {
-  const host = canonical.provenance.host;
-  const normalized = host === 'claude'
-    ? normalizeClaudeHook(native)
-    : host === 'codex'
-      ? normalizeCodexHook(native)
-      : undefined;
-  if (normalized === undefined) {
-    throw new Error(`Unsupported event-route host ${JSON.stringify(host)}`);
-  }
+  try {
+    const host = canonical.provenance.host;
+    const normalized = host === 'claude'
+      ? normalizeClaudeHook(native)
+      : host === 'codex'
+        ? normalizeCodexHook(native)
+        : undefined;
+    if (normalized === undefined) {
+      throw new Error(`Unsupported event-route host ${JSON.stringify(host)}`);
+    }
 
-  const configuredStateFile = process.env.AGENT_RUNTIME_STATE_FILE;
-  const stateFile = configuredStateFile === undefined || configuredStateFile.trim() === ''
-    ? await resolveImplicitRuntimeStateFile(normalized.cwd)
-    : resolve(configuredStateFile);
-  const snapshot = await createFileRuntimeKernel({ stateFile }).recordEdit({
-    host: normalized.host,
-    idempotencyKey: canonical.idempotencyKey,
-    path: normalized.path,
-    sessionId: normalized.sessionId,
-    toolName: normalized.toolName,
-  }, { signal });
-  const editNoun = snapshot.stateVersion === 1 ? 'edit' : 'edits';
+    const configuredStateFile = process.env.AGENT_RUNTIME_STATE_FILE;
+    const stateFile = configuredStateFile === undefined || configuredStateFile.trim() === ''
+      ? await resolveImplicitRuntimeStateFile(normalized.cwd)
+      : resolve(configuredStateFile);
+    const snapshot = await createFileRuntimeKernel({ stateFile }).recordEdit({
+      host: normalized.host,
+      idempotencyKey: canonical.idempotencyKey,
+      path: normalized.path,
+      sessionId: normalized.sessionId,
+      toolName: normalized.toolName,
+    }, { signal });
+    const editNoun = snapshot.stateVersion === 1 ? 'edit' : 'edits';
+    await writeEvalProbe(native, 0);
 
-  return (
-    <Agent.Result>
-      <Agent.Context>
-        {`Recorded ${basename(normalized.path)} from ${normalized.host}. Shared state now contains ${snapshot.stateVersion} ${editNoun}.`}
-      </Agent.Context>
-    </Agent.Result>
-  );
+    return (
+      <Agent.Result>
+        <Agent.Context>
+          {`Recorded ${basename(normalized.path)} from ${normalized.host}. Shared state now contains ${snapshot.stateVersion} ${editNoun}.`}
+        </Agent.Context>
+      </Agent.Result>
+    );
+  } catch (error) {
+    await writeEvalProbe(native, 1).catch(() => undefined);
+    throw error;
+  }
 }
diff --git a/examples/rsc-agent-runtime/src/hook/cli.ts b/examples/rsc-agent-runtime/src/hook/cli.ts
index c7e93dcb6..a0681b95a 100644
--- a/examples/rsc-agent-runtime/src/hook/cli.ts
+++ b/examples/rsc-agent-runtime/src/hook/cli.ts
@@ -1,40 +1,13 @@
-import { appendFile } from 'node:fs/promises';
 import { resolve } from 'node:path';
 
 import { requestAgentDocument } from '../flight/request-render.js';
 import { resolveImplicitRuntimeStateFile } from '../runtime/state-file.js';
+import { writeEvalProbe } from './eval-probe.js';
 import { normalizeClaudeHook, normalizeCodexHook } from './normalize.js';
 import { projectHookDocument } from './project-document.js';
 
 let probeInput: Record<string, unknown> | undefined;
 
-const valueType = (value: unknown): string => {
-  if (value === null) return 'null';
-  if (Array.isArray(value)) return 'array';
-  return typeof value;
-};
-
-const writeEvalProbe = async (input: Record<string, unknown>, exitStatus: number): Promise<void> => {
-  const probeFile = process.env.AGENT_RUNTIME_HOOK_PROBE_FILE;
-  if (probeFile === undefined || probeFile.trim() === '') return;
-
-  const toolInput = input.tool_input;
-  const toolInputRecord = toolInput !== null && typeof toolInput === 'object' && !Array.isArray(toolInput)
-    ? toolInput as Record<string, unknown>
-    : undefined;
-  const topLevelKeys = Object.keys(input).sort();
-  const toolInputKeys = toolInputRecord === undefined ? [] : Object.keys(toolInputRecord).sort();
-  await appendFile(probeFile, `${JSON.stringify({
-    commandLaunched: true,
-    exitStatus,
-    toolInputKeys,
-    toolInputValueTypes: Object.fromEntries(toolInputKeys.map((key) => [key, valueType(toolInputRecord?.[key])])),
-    toolName: typeof input.tool_name === 'string' ? input.tool_name : undefined,
-    topLevelKeys,
-    topLevelValueTypes: Object.fromEntries(topLevelKeys.map((key) => [key, valueType(input[key])])),
-  })}\n`);
-};
-
 const readInput = async (): Promise<Record<string, unknown>> => {
   let contents = '';
   process.stdin.setEncoding('utf8');
diff --git a/examples/rsc-agent-runtime/src/hook/eval-probe.ts b/examples/rsc-agent-runtime/src/hook/eval-probe.ts
new file mode 100644
index 000000000..45fc1ec7d
--- /dev/null
+++ b/examples/rsc-agent-runtime/src/hook/eval-probe.ts
@@ -0,0 +1,28 @@
+import { appendFile } from 'node:fs/promises';
+
+const valueType = (value: unknown): string => {
+  if (value === null) return 'null';
+  if (Array.isArray(value)) return 'array';
+  return typeof value;
+};
+
+export const writeEvalProbe = async (input: Record<string, unknown>, exitStatus: number): Promise<void> => {
+  const probeFile = process.env.AGENT_RUNTIME_HOOK_PROBE_FILE;
+  if (probeFile === undefined || probeFile.trim() === '') return;
+
+  const toolInput = input.tool_input;
+  const toolInputRecord = toolInput !== null && typeof toolInput === 'object' && !Array.isArray(toolInput)
+    ? toolInput as Record<string, unknown>
+    : undefined;
+  const topLevelKeys = Object.keys(input).sort();
+  const toolInputKeys = toolInputRecord === undefined ? [] : Object.keys(toolInputRecord).sort();
+  await appendFile(probeFile, `${JSON.stringify({
+    commandLaunched: true,
+    exitStatus,
+    toolInputKeys,
+    toolInputValueTypes: Object.fromEntries(toolInputKeys.map((key) => [key, valueType(toolInputRecord?.[key])])),
+    toolName: typeof input.tool_name === 'string' ? input.tool_name : undefined,
+    topLevelKeys,
+    topLevelValueTypes: Object.fromEntries(topLevelKeys.map((key) => [key, valueType(input[key])])),
+  })}\n`);
+};
diff --git a/examples/rsc-agent-runtime/tests/route-unit/event-route.test.ts b/examples/rsc-agent-runtime/tests/route-unit/event-route.test.ts
index ffa5040bc..021a3d5e0 100644
--- a/examples/rsc-agent-runtime/tests/route-unit/event-route.test.ts
+++ b/examples/rsc-agent-runtime/tests/route-unit/event-route.test.ts
@@ -17,16 +17,20 @@ const fixture = resolve(import.meta.dirname, '../fixtures/events/claude-post-too
 
 let workspace: string;
 let previousStateFile: string | undefined;
+let previousProbeFile: string | undefined;
 
 beforeEach(async () => {
   workspace = await mkdtemp(join(tmpdir(), 'rsc-agent-runtime-event-route-'));
   previousStateFile = process.env.AGENT_RUNTIME_STATE_FILE;
+  previousProbeFile = process.env.AGENT_RUNTIME_HOOK_PROBE_FILE;
   process.env.AGENT_RUNTIME_STATE_FILE = join(workspace, 'state.json');
 });
 
 afterEach(async () => {
   if (previousStateFile === undefined) delete process.env.AGENT_RUNTIME_STATE_FILE;
   else process.env.AGENT_RUNTIME_STATE_FILE = previousStateFile;
+  if (previousProbeFile === undefined) delete process.env.AGENT_RUNTIME_HOOK_PROBE_FILE;
+  else process.env.AGENT_RUNTIME_HOOK_PROBE_FILE = previousProbeFile;
   await rm(workspace, { force: true, recursive: true });
 });
 
@@ -66,3 +70,48 @@ it('renders a native Claude PostToolUse envelope into the document the host proj
     .toContainContext('Recorded claude-note.txt from claude. Shared state now contains 1 edit.');
   expect(rendered.provenance).toMatchObject({ kind: 'event-route', proofLevel: 'route-unit' });
 });
+
+it('appends a value-free eval hook probe when AGENT_RUNTIME_HOOK_PROBE_FILE is set', async () => {
+  const probeFile = join(workspace, 'hook-probe.jsonl');
+  process.env.AGENT_RUNTIME_HOOK_PROBE_FILE = probeFile;
+  const native = JSON.parse(await readFile(fixture, 'utf8')) as Record<string, unknown>;
+
+  await renderRoute('event:tool/after', {
+    input: {
+      canonical: {
+        event: 'tool/after',
+        idempotencyKey: 'route-unit-claude-write',
+        observedAt: '2026-09-01T00:00:00.000Z',
+        provenance: {
+          host: 'claude',
+          hostContractRevision: 'route-unit',
+          nativeEvent: 'PostToolUse',
+          source: 'native',
+        },
+        sequence: 1,
+      },
+      native: { ...native, cwd: workspace },
+    },
+  });
+
+  const probe = JSON.parse(await readFile(probeFile, 'utf8'));
+  expect(probe).toEqual({
+    commandLaunched: true,
+    exitStatus: 0,
+    toolInputKeys: ['file_path'],
+    toolInputValueTypes: { file_path: 'string' },
+    toolName: 'Write',
+    topLevelKeys: ['cwd', 'hook_event_name', 'session_id', 'tool_input', 'tool_name', 'tool_response', 'tool_use_id', 'transcript_path'],
+    topLevelValueTypes: {
+      cwd: 'string',
+      hook_event_name: 'string',
+      session_id: 'string',
+      tool_input: 'object',
+      tool_name: 'string',
+      tool_response: 'object',
+      tool_use_id: 'string',
+      transcript_path: 'string',
+    },
+  });
+  expect(await readFile(probeFile, 'utf8')).not.toContain('claude-note.txt');
+});