diff --git a/src/api/http.zig b/src/api/http.zig
index d4377633..68311d08 100644
--- a/src/api/http.zig
+++ b/src/api/http.zig
@@ -11,7 +11,7 @@ pub const request_timeout_ms = types.request_timeout_ms;
 pub const request_timeout_ms_value = types.request_timeout_ms_value;
 pub const child_process_timeout_ms = types.child_process_timeout_ms;
 pub const child_process_timeout_ms_value = types.child_process_timeout_ms_value;
-pub const browser_user_agent = types.browser_user_agent;
+pub const user_agent = types.user_agent;
 pub const node_executable_env = types.node_executable_env;
 pub const node_use_env_proxy_env = types.node_use_env_proxy_env;
 pub const node_requirement_hint = types.node_requirement_hint;
diff --git a/src/api/http_node.zig b/src/api/http_node.zig
index db3f9eda..9c042fef 100644
--- a/src/api/http_node.zig
+++ b/src/api/http_node.zig
@@ -13,7 +13,7 @@ const BatchItemResult = types.BatchItemResult;
 const request_timeout_ms = types.request_timeout_ms;
 const request_timeout_ms_value = types.request_timeout_ms_value;
 const child_process_timeout_ms_value = types.child_process_timeout_ms_value;
-const browser_user_agent = types.browser_user_agent;
+const user_agent = types.user_agent;
 const getEnvMap = env.getEnvMap;
 const resolveNodeExecutable = executable.resolveNodeExecutable;
 const resolveNodeExecutableForLaunchAlloc = executable.resolveNodeExecutableForLaunchAlloc;
@@ -266,7 +266,7 @@ fn runNodeBearerGetJsonCommand(
         endpoint,
         access_token,
         request_timeout_ms,
-        browser_user_agent,
+        user_agent,
     }, child_process_timeout_ms_value, &env_map) catch |err| switch (err) {
         error.OutOfMemory => return err,
         error.FileNotFound => {
@@ -334,7 +334,7 @@ fn runNodeGetJsonCommand(
         access_token,
         account_id,
         request_timeout_ms,
-        browser_user_agent,
+        user_agent,
     }, child_process_timeout_ms_value, &env_map) catch |err| switch (err) {
         error.OutOfMemory => return err,
         error.FileNotFound => {
@@ -411,7 +411,7 @@ fn runNodeGetJsonBatchCommand(
         .endpoint = endpoint,
         .timeout_ms = request_timeout_ms_value,
         .concurrency = @max(@as(usize, 1), max_concurrency),
-        .user_agent = browser_user_agent,
+        .user_agent = user_agent,
         .requests = requests,
     }, .{}, &payload_writer.writer);
 
diff --git a/src/api/http_types.zig b/src/api/http_types.zig
index c664e38c..34f356ff 100644
--- a/src/api/http_types.zig
+++ b/src/api/http_types.zig
@@ -1,11 +1,12 @@
 const std = @import("std");
+const version = @import("../version.zig");
 
 pub const request_timeout_secs: []const u8 = "5";
 pub const request_timeout_ms: []const u8 = "5000";
 pub const request_timeout_ms_value: u64 = 5000;
 pub const child_process_timeout_ms: []const u8 = "7000";
 pub const child_process_timeout_ms_value: u64 = 7000;
-pub const browser_user_agent: []const u8 = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36";
+pub const user_agent: []const u8 = "codex-auth/" ++ version.app_version;
 pub const node_executable_env = "CODEX_AUTH_NODE_EXECUTABLE";
 pub const node_use_env_proxy_env = "NODE_USE_ENV_PROXY";
 pub const node_requirement_hint = "Node.js 22+ is required for ChatGPT API refresh. Install Node.js 22+ or use the npm package.";