From 6ae2bcc75078693bd7814b441fec59e407516913 Mon Sep 17 00:00:00 2001
From: Wooseong Kim <innocarpe@gmail.com>
Date: Thu, 6 Aug 2026 17:46:33 +0900
Subject: [PATCH 1/2] fix: add User-Agent header to OpenAI client fetch (#177)

Some CDNs and WAFs (e.g. Cloudflare) block requests that arrive without a User-Agent. Inject a default one into the undici fetch wrapper, preserving any caller-provided headers.

(cherry picked from commit 67a33160c870c301342eb6b3a70ae01609976c7e)
---
 packages/core/src/common/openai-client.ts     | 17 ++++++++++++++-
 packages/core/src/tests/openai-client.test.ts | 21 +++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)
 create mode 100644 packages/core/src/tests/openai-client.test.ts

diff --git a/packages/core/src/common/openai-client.ts b/packages/core/src/common/openai-client.ts
index d3b56c08..f80a780a 100644
--- a/packages/core/src/common/openai-client.ts
+++ b/packages/core/src/common/openai-client.ts
@@ -3,6 +3,7 @@ import * as os from "os";
 import * as path from "path";
 import OpenAI from "openai";
 import { Agent, fetch as undiciFetch } from "undici";
+import type { HeadersInit } from "undici";
 import { resolveCurrentSettings } from "../settings";
 
 // Custom undici Agent with a 180-second keepAlive timeout.  The default
@@ -12,6 +13,19 @@ import { resolveCurrentSettings } from "../settings";
 // keep connections reusable for three minutes after the last request.
 const keepAliveAgent = new Agent({ keepAliveTimeout: 180_000 });
 
+const DEFAULT_USER_AGENT = `deepcode-cli (Node.js ${process.version})`;
+
+// Inject a default User-Agent header into outgoing requests. Some CDNs and
+// WAFs (e.g. Cloudflare) block requests that arrive without a User-Agent as a
+// basic anti-bot measure. (#177)
+export function buildClientHeaders(initHeaders?: HeadersInit): Headers {
+  const headers = new Headers(initHeaders);
+  if (!headers.has("User-Agent")) {
+    headers.set("User-Agent", DEFAULT_USER_AGENT);
+  }
+  return headers;
+}
+
 // Module-level cache for the OpenAI client instance.  The client itself is
 // a stateless fetch wrapper, so it is safe to share across calls as long as
 // the apiKey + baseURL stay the same.  Model, thinking-mode and other
@@ -73,7 +87,8 @@ export function createOpenAIClient(projectRoot: string = process.cwd()): {
     apiKey: settings.apiKey,
     baseURL: settings.baseURL || undefined,
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    fetch: (url: any, init: any) => undiciFetch(url, { ...init, dispatcher: keepAliveAgent }),
+    fetch: (url: any, init: any) =>
+      undiciFetch(url, { ...init, headers: buildClientHeaders(init?.headers), dispatcher: keepAliveAgent }),
   });
   cachedOpenAIKey = cacheKey;
 
diff --git a/packages/core/src/tests/openai-client.test.ts b/packages/core/src/tests/openai-client.test.ts
new file mode 100644
index 00000000..9f9be693
--- /dev/null
+++ b/packages/core/src/tests/openai-client.test.ts
@@ -0,0 +1,21 @@
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { buildClientHeaders } from "../common/openai-client";
+
+test("buildClientHeaders injects a default User-Agent when none is set", () => {
+  const headers = buildClientHeaders(undefined);
+  assert.match(headers.get("User-Agent") ?? "", /^deepcode-cli \(Node\.js v\d+\.\d+\.\d+\)$/);
+});
+
+test("buildClientHeaders preserves existing headers and a custom User-Agent", () => {
+  const headers = buildClientHeaders({ Authorization: "Bearer sk-test", "User-Agent": "custom-agent" });
+  assert.equal(headers.get("Authorization"), "Bearer sk-test");
+  assert.equal(headers.get("User-Agent"), "custom-agent");
+});
+
+test("buildClientHeaders accepts a Headers instance and keeps its entries", () => {
+  const source = new Headers({ "Content-Type": "application/json" });
+  const headers = buildClientHeaders(source);
+  assert.equal(headers.get("Content-Type"), "application/json");
+  assert.match(headers.get("User-Agent") ?? "", /^deepcode-cli /);
+});

From b12ae48c2f0d120da0aaeb06bf02c10a757ed584 Mon Sep 17 00:00:00 2001
From: Wooseong Kim <innocarpe@gmail.com>
Date: Thu, 6 Aug 2026 18:20:53 +0900
Subject: [PATCH 2/2] test: use tuple-array HeadersInit in openai-client header
 test

The undici HeadersInit type used by buildClientHeaders does not accept the global Headers instance in this project's TS config, so switch the test to a tuple-array input.

(cherry picked from commit 8ee5241e83e602a87fd64151997dad06b79708f6)
---
 packages/core/src/tests/openai-client.test.ts | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/packages/core/src/tests/openai-client.test.ts b/packages/core/src/tests/openai-client.test.ts
index 9f9be693..6bb57d7a 100644
--- a/packages/core/src/tests/openai-client.test.ts
+++ b/packages/core/src/tests/openai-client.test.ts
@@ -13,9 +13,8 @@ test("buildClientHeaders preserves existing headers and a custom User-Agent", ()
   assert.equal(headers.get("User-Agent"), "custom-agent");
 });
 
-test("buildClientHeaders accepts a Headers instance and keeps its entries", () => {
-  const source = new Headers({ "Content-Type": "application/json" });
-  const headers = buildClientHeaders(source);
+test("buildClientHeaders accepts tuple-array headers and keeps its entries", () => {
+  const headers = buildClientHeaders([["Content-Type", "application/json"]]);
   assert.equal(headers.get("Content-Type"), "application/json");
   assert.match(headers.get("User-Agent") ?? "", /^deepcode-cli /);
 });