diff --git a/containers/api-proxy/server.anthropic-beta.test.js b/containers/api-proxy/server.anthropic-beta.test.js
index aaf7283a7..e536082cb 100644
--- a/containers/api-proxy/server.anthropic-beta.test.js
+++ b/containers/api-proxy/server.anthropic-beta.test.js
@@ -6,7 +6,13 @@
  */
 
 const https = require('https');
-const { EventEmitter } = require('events');
+const {
+  makeReq: makeReqFactory,
+  makeRes,
+  makeProxyReq,
+  makeProxyRes,
+  getStructuredLogs,
+} = require('./test-helpers/server-mock-factories');
 
 const originalHttpsProxy = process.env.HTTPS_PROXY;
 let proxyRequest;
@@ -34,52 +40,7 @@ afterAll(() => {
 
 describe('proxyRequest anthropic deprecated beta handling', () => {
   function makeReq(headers = {}) {
-    const req = new EventEmitter();
-    req.url = '/v1/messages';
-    req.method = 'POST';
-    req.headers = { 'content-type': 'application/json', ...headers };
-    return req;
-  }
-
-  function makeRes() {
-    const res = {
-      headersSent: false,
-      setHeader: jest.fn(),
-      writeHead: jest.fn(() => {
-        res.headersSent = true;
-      }),
-      end: jest.fn(),
-      destroy: jest.fn(),
-    };
-    return res;
-  }
-
-  function makeProxyReq() {
-    const proxyReq = new EventEmitter();
-    proxyReq.end = jest.fn();
-    proxyReq.write = jest.fn();
-    proxyReq.destroy = jest.fn();
-    return proxyReq;
-  }
-
-  function makeProxyRes(statusCode, headers = { 'content-type': 'application/json' }) {
-    const proxyRes = new EventEmitter();
-    proxyRes.statusCode = statusCode;
-    proxyRes.headers = headers;
-    proxyRes.pipe = jest.fn();
-    return proxyRes;
-  }
-
-  function getStructuredLogs(writeSpy, eventName) {
-    return writeSpy.mock.calls
-      .map(([line]) => {
-        try {
-          return JSON.parse(line);
-        } catch {
-          return null;
-        }
-      })
-      .filter(entry => entry && entry.event === eventName);
+    return makeReqFactory('/v1/messages', headers);
   }
 
   afterEach(() => {
diff --git a/containers/api-proxy/server.error-handling.test.js b/containers/api-proxy/server.error-handling.test.js
index 8e105b792..3676ea96b 100644
--- a/containers/api-proxy/server.error-handling.test.js
+++ b/containers/api-proxy/server.error-handling.test.js
@@ -7,6 +7,11 @@
 
 const https = require('https');
 const { EventEmitter } = require('events');
+const {
+  makeReq: makeReqFactory,
+  makeRes,
+  getStructuredLogs,
+} = require('./test-helpers/server-mock-factories');
 
 const originalHttpsProxy = process.env.HTTPS_PROXY;
 let proxyRequest;
@@ -29,36 +34,11 @@ afterAll(() => {
 
 describe('proxyRequest error handling', () => {
   function makeReq(headers = {}) {
-    const req = new EventEmitter();
-    req.url = '/v1/chat/completions';
-    req.method = 'POST';
-    req.headers = { 'content-type': 'application/json', ...headers };
-    return req;
-  }
-
-  function makeRes() {
-    const res = {
-      headersSent: false,
-      setHeader: jest.fn(),
-      writeHead: jest.fn(() => {
-        res.headersSent = true;
-      }),
-      end: jest.fn(),
-      destroy: jest.fn(),
-    };
-    return res;
+    return makeReqFactory('/v1/chat/completions', headers);
   }
 
   function getRequestErrorLog(writeSpy) {
-    for (const [line] of writeSpy.mock.calls) {
-      try {
-        const parsed = JSON.parse(line);
-        if (parsed.event === 'request_error') return parsed;
-      } catch {
-        // ignore non-JSON writes
-      }
-    }
-    return null;
+    return getStructuredLogs(writeSpy, 'request_error')[0] || null;
   }
 
   let stdoutWriteSpy;
diff --git a/containers/api-proxy/server.model-not-supported.test.js b/containers/api-proxy/server.model-not-supported.test.js
index 1c7a7e8cb..19f6b40c8 100644
--- a/containers/api-proxy/server.model-not-supported.test.js
+++ b/containers/api-proxy/server.model-not-supported.test.js
@@ -7,7 +7,13 @@
  */
 
 const https = require('https');
-const { EventEmitter } = require('events');
+const {
+  makeReq: makeReqFactory,
+  makeRes,
+  makeProxyReq,
+  makeProxyRes,
+  getStructuredLogs,
+} = require('./test-helpers/server-mock-factories');
 
 const originalHttpsProxy = process.env.HTTPS_PROXY;
 let proxyRequest;
@@ -36,38 +42,7 @@ afterAll(() => {
 // ── helpers ───────────────────────────────────────────────────────────────────
 
 function makeReq(headers = {}) {
-  const req = new EventEmitter();
-  req.url = '/v1/chat/completions';
-  req.method = 'POST';
-  req.headers = { 'content-type': 'application/json', ...headers };
-  return req;
-}
-
-function makeRes() {
-  const res = {
-    headersSent: false,
-    setHeader: jest.fn(),
-    writeHead: jest.fn(() => { res.headersSent = true; }),
-    end: jest.fn(),
-    destroy: jest.fn(),
-  };
-  return res;
-}
-
-function makeProxyReq() {
-  const proxyReq = new EventEmitter();
-  proxyReq.end = jest.fn();
-  proxyReq.write = jest.fn();
-  proxyReq.destroy = jest.fn();
-  return proxyReq;
-}
-
-function makeProxyRes(statusCode, headers = { 'content-type': 'application/json' }) {
-  const proxyRes = new EventEmitter();
-  proxyRes.statusCode = statusCode;
-  proxyRes.headers = headers;
-  proxyRes.pipe = jest.fn();
-  return proxyRes;
+  return makeReqFactory('/v1/chat/completions', headers);
 }
 
 /** Flush all pending microtasks/promises so async retry callbacks can run. */
@@ -75,12 +50,6 @@ function flushPromises() {
   return new Promise(resolve => setImmediate(resolve));
 }
 
-function getStructuredLogs(writeSpy, eventName) {
-  return writeSpy.mock.calls
-    .map(([line]) => { try { return JSON.parse(line); } catch { return null; } })
-    .filter(entry => entry && entry.event === eventName);
-}
-
 // ── tests ─────────────────────────────────────────────────────────────────────
 
 describe('proxyRequest copilot model-not-supported retry', () => {
diff --git a/containers/api-proxy/server.proxy-headers.test.js b/containers/api-proxy/server.proxy-headers.test.js
index b69ed5631..3397b2951 100644
--- a/containers/api-proxy/server.proxy-headers.test.js
+++ b/containers/api-proxy/server.proxy-headers.test.js
@@ -5,7 +5,11 @@
  */
 
 const https = require('https');
-const { EventEmitter } = require('events');
+const {
+  makeReq: makeReqFactory,
+  makeRes,
+  makeProxyReq,
+} = require('./test-helpers/server-mock-factories');
 
 const originalHttpsProxy = process.env.HTTPS_PROXY;
 let proxyRequest;
@@ -28,21 +32,7 @@ afterAll(() => {
 describe('proxyRequest X-Initiator injection', () => {
   /** Minimal mock for http.IncomingMessage backed by EventEmitter. */
   function makeReq(headers = {}) {
-    const req = new EventEmitter();
-    req.url = '/v1/chat/completions';
-    req.method = 'POST';
-    req.headers = { 'content-type': 'application/json', ...headers };
-    return req;
-  }
-
-  /** Minimal mock for http.ServerResponse. */
-  function makeRes() {
-    return {
-      headersSent: false,
-      setHeader: jest.fn(),
-      writeHead: jest.fn(),
-      end: jest.fn(),
-    };
+    return makeReqFactory('/v1/chat/completions', headers);
   }
 
   afterEach(() => {
@@ -58,10 +48,7 @@ describe('proxyRequest X-Initiator injection', () => {
     let capturedProxyReq;
     jest.spyOn(https, 'request').mockImplementation((options) => {
       capturedOptions = options;
-      const proxyReq = new EventEmitter();
-      proxyReq.end = jest.fn();
-      proxyReq.write = jest.fn();
-      proxyReq.destroy = jest.fn();
+      const proxyReq = makeProxyReq();
       capturedProxyReq = proxyReq;
       return proxyReq;
     });
diff --git a/containers/api-proxy/server.token-guards.test.js b/containers/api-proxy/server.token-guards.test.js
index 9a358a087..58e7b45a9 100644
--- a/containers/api-proxy/server.token-guards.test.js
+++ b/containers/api-proxy/server.token-guards.test.js
@@ -7,6 +7,7 @@
 
 const https = require('https');
 const { EventEmitter } = require('events');
+const { makeReq: makeReqFactory, makeRes } = require('./test-helpers/server-mock-factories');
 
 const originalHttpsProxy = process.env.HTTPS_PROXY;
 let proxyRequest;
@@ -34,20 +35,7 @@ afterAll(() => {
 
 describe('proxyRequest effective token guard', () => {
   function makeReq(headers = {}) {
-    const req = new EventEmitter();
-    req.url = '/v1/chat/completions';
-    req.method = 'POST';
-    req.headers = { 'content-type': 'application/json', ...headers };
-    return req;
-  }
-
-  function makeRes() {
-    return {
-      headersSent: false,
-      setHeader: jest.fn(),
-      writeHead: jest.fn(),
-      end: jest.fn(),
-    };
+    return makeReqFactory('/v1/chat/completions', headers);
   }
 
   beforeEach(() => {
@@ -113,20 +101,7 @@ describe('proxyRequest effective token guard', () => {
 
 describe('proxyRequest max-runs guard', () => {
   function makeReq(headers = {}) {
-    const req = new EventEmitter();
-    req.url = '/v1/chat/completions';
-    req.method = 'POST';
-    req.headers = { 'content-type': 'application/json', ...headers };
-    return req;
-  }
-
-  function makeRes() {
-    return {
-      headersSent: false,
-      setHeader: jest.fn(),
-      writeHead: jest.fn(),
-      end: jest.fn(),
-    };
+    return makeReqFactory('/v1/chat/completions', headers);
   }
 
   beforeEach(() => {
diff --git a/containers/api-proxy/test-helpers/server-mock-factories.js b/containers/api-proxy/test-helpers/server-mock-factories.js
new file mode 100644
index 000000000..4a050acb0
--- /dev/null
+++ b/containers/api-proxy/test-helpers/server-mock-factories.js
@@ -0,0 +1,54 @@
+'use strict';
+
+const { EventEmitter } = require('events');
+
+function makeReq(url, headers = {}) {
+  const req = new EventEmitter();
+  req.url = url;
+  req.method = 'POST';
+  req.headers = { 'content-type': 'application/json', ...headers };
+  return req;
+}
+
+function makeRes() {
+  const res = {
+    headersSent: false,
+    setHeader: jest.fn(),
+    writeHead: jest.fn(() => {
+      res.headersSent = true;
+    }),
+    end: jest.fn(),
+    destroy: jest.fn(),
+  };
+  return res;
+}
+
+function makeProxyReq() {
+  const proxyReq = new EventEmitter();
+  proxyReq.end = jest.fn();
+  proxyReq.write = jest.fn();
+  proxyReq.destroy = jest.fn();
+  return proxyReq;
+}
+
+function makeProxyRes(statusCode, headers = { 'content-type': 'application/json' }) {
+  const proxyRes = new EventEmitter();
+  proxyRes.statusCode = statusCode;
+  proxyRes.headers = headers;
+  proxyRes.pipe = jest.fn();
+  return proxyRes;
+}
+
+function getStructuredLogs(writeSpy, eventName) {
+  return writeSpy.mock.calls
+    .map(([line]) => {
+      try {
+        return JSON.parse(line);
+      } catch {
+        return null;
+      }
+    })
+    .filter(entry => entry && entry.event === eventName);
+}
+
+module.exports = { makeReq, makeRes, makeProxyReq, makeProxyRes, getStructuredLogs };