diff --git a/ui/desktop/src/acp/__tests__/recipeParamRequests.test.ts b/ui/desktop/src/acp/__tests__/recipeParamRequests.test.ts
index f3e28a92d..41acd24c4 100644
--- a/ui/desktop/src/acp/__tests__/recipeParamRequests.test.ts
+++ b/ui/desktop/src/acp/__tests__/recipeParamRequests.test.ts
@@ -82,6 +82,27 @@ describe('ACP recipe param requests', () => {
     scope.finish();
   });
 
+  it('does not offer deeplink values for file parameters', async () => {
+    setRecipeParameters({ document: '/tmp/private.txt', topic: 'release notes' });
+    const scope = requests.beginConfiguredRecipeParameterScope()!;
+    const request = recipeParamRequest('session-1', scope.id);
+    request.parameters.unshift({
+      key: 'document',
+      description: 'Document',
+      input_type: 'file',
+      requirement: 'required',
+    });
+
+    const response = requests.requestAcpRecipeParams(request);
+    const [pendingRequest] = requests.getAcpRecipeParamRequestsSnapshot();
+
+    expect(pendingRequest.initialValues).toEqual({ topic: 'release notes' });
+
+    requests.cancelAcpRecipeParamRequest(pendingRequest.id);
+    await expect(response).resolves.toEqual({ action: 'cancel' });
+    scope.finish();
+  });
+
   it('allows same-session retries until a terminal response consumes the values', async () => {
     setRecipeParameters({ topic: 'release notes' });
     const scope = requests.beginConfiguredRecipeParameterScope()!;
diff --git a/ui/desktop/src/acp/recipeParamRequests.ts b/ui/desktop/src/acp/recipeParamRequests.ts
index 0b9a465f2..592a0a115 100644
--- a/ui/desktop/src/acp/recipeParamRequests.ts
+++ b/ui/desktop/src/acp/recipeParamRequests.ts
@@ -81,8 +81,7 @@ export function beginConfiguredRecipeParameterScope(): ConfiguredRecipeParameter
   }
 
   const configured = window.appConfig?.get('recipeParameters') as
-    | Record<string, string>
-    | undefined;
+    Record<string, string> | undefined;
   if (!configured || Object.keys(configured).length === 0) {
     configuredParameterState = { status: 'consumed' };
     return undefined;
@@ -122,8 +121,15 @@ function configuredParameterValues(request: RequestRecipeParams_unstable): {
   if (configuredParameterState.sessionId !== request.sessionId) {
     return { values: {}, usesConfiguredParameters: false };
   }
+  const fileParameterKeys = new Set(
+    request.parameters
+      .filter((parameter) => parameter.input_type === 'file')
+      .map((parameter) => parameter.key)
+  );
   return {
-    values: { ...configuredParameterState.values },
+    values: Object.fromEntries(
+      Object.entries(configuredParameterState.values).filter(([key]) => !fileParameterKeys.has(key))
+    ),
     usesConfiguredParameters: true,
   };
 }
diff --git a/ui/desktop/src/components/ParameterInputModal.tsx b/ui/desktop/src/components/ParameterInputModal.tsx
index 23bd753a7..fb8448f07 100644
--- a/ui/desktop/src/components/ParameterInputModal.tsx
+++ b/ui/desktop/src/components/ParameterInputModal.tsx
@@ -101,6 +101,10 @@ const ParameterInputModal: React.FC<ParameterInputModalProps> = ({
   useEffect(() => {
     const values = createParameterValueMap();
     parameters.forEach((param) => {
+      if (param.input_type === 'file') {
+        return;
+      }
+
       if (param.requirement === 'optional' && param.default != null) {
         if (isValidParameterValue(param, param.default)) {
           values[param.key] = param.default;
diff --git a/ui/desktop/src/components/__tests__/ParameterInputModal.test.tsx b/ui/desktop/src/components/__tests__/ParameterInputModal.test.tsx
index 79e2f7491..97b8fc7c8 100644
--- a/ui/desktop/src/components/__tests__/ParameterInputModal.test.tsx
+++ b/ui/desktop/src/components/__tests__/ParameterInputModal.test.tsx
@@ -507,6 +507,44 @@ describe('ParameterInputModal', () => {
       expect((screen.getByLabelText(/boolean parameter/i) as HTMLSelectElement).value).toBe('true');
     });
 
+    it('does not initialize file parameters from prefills or defaults', async () => {
+      const user = userEvent.setup();
+      const onSubmit = vi.fn();
+      renderWithIntl(
+        <ParameterInputModal
+          {...defaultProps}
+          onSubmit={onSubmit}
+          parameters={[
+            {
+              key: 'document',
+              description: 'Document',
+              input_type: 'file',
+              requirement: 'required',
+              default: '/tmp/default.txt',
+            },
+            {
+              key: 'topic',
+              description: 'Topic',
+              input_type: 'string',
+              requirement: 'required',
+            },
+          ]}
+          initialValues={{ document: '/tmp/private.txt', topic: 'release notes' }}
+        />
+      );
+
+      expect(screen.getByLabelText(/^Document/)).toHaveValue('');
+      expect(screen.getByLabelText(/^Topic/)).toHaveValue('release notes');
+
+      await user.type(screen.getByLabelText(/^Document/), '/tmp/selected.txt');
+      await user.click(screen.getByText('Start Recipe'));
+
+      expect(onSubmit).toHaveBeenCalledWith({
+        document: '/tmp/selected.txt',
+        topic: 'release notes',
+      });
+    });
+
     it('keeps a valid default when an invalid prefill is supplied', () => {
       renderWithIntl(
         <ParameterInputModal