From 6f809bb970cc466d7d8ca2f53b49aca87997c480 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Fri, 25 Sep 2026 17:29:39 +0000
Subject: [PATCH] feat(gateway): recognise Antigravity CLI requests as
 antigravity-cli

Antigravity CLI (agy) has no user agent of its own. Pointed at a custom
Gemini endpoint (GOOGLE_GEMINI_BASE_URL + GEMINI_API_KEY with
modelProvider "gemini"), agy 1.2.11 sends the Go genai SDK default in
both User-Agent and X-Goog-Api-Client:

    google-genai-sdk/1.71.0 gl-go/go1.28-20260721-RC03 cl/951519500 +3ebc191975 X:fieldtrack,...

Matching on `google-genai-sdk` alone would label every Go program built
on the SDK as agy. What sets agy apart is the Google-internal Go
toolchain version after `gl-go/` (it carries `cl/<number>`); a program
built with a public Go release sends `gl-go/go1.25.1`. The hint now maps
that combination to `antigravity-cli`, the client id ThinkWatch Lite
uses for it.

Captured by running agy against a local fake server with a fake key and
all outbound traffic blocked; no account was signed in.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012JfMJSMbfEW5nzkn9vro9A
---
 crates/tw-gateway/src/hint.rs | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/crates/tw-gateway/src/hint.rs b/crates/tw-gateway/src/hint.rs
index ae93fa7d..18d3f0f5 100644
--- a/crates/tw-gateway/src/hint.rs
+++ b/crates/tw-gateway/src/hint.rs
@@ -51,6 +51,14 @@ pub fn client_hint(headers: &HeaderMap) -> Option<String> {
             return Some(id.into());
         }
     }
+    // 四、Antigravity CLI（agy）。它没有自己的 UA，发的是 Go 版 genai SDK 的默认值。
+    // 实测 1.2.11：`google-genai-sdk/1.71.0 gl-go/go1.28-20260721-RC03 cl/951519500 +3ebc191975 X:…`
+    // 只看 `google-genai-sdk` 会把任何用 Go SDK 的程序都算成 agy；能分开的是
+    // `gl-go/` 后面那段 Google 内部 Go 工具链的版本号（带 `cl/`），外面编出来的只有
+    // `gl-go/go1.25.1`。
+    if ua.starts_with("google-genai-sdk/") && ua.contains(" gl-go/") && ua.contains(" cl/") {
+        return Some("antigravity-cli".into());
+    }
     None
 }
 
@@ -120,6 +128,28 @@ mod tests {
         );
     }
 
+    #[test]
+    fn antigravity_cli_is_recognised_by_the_toolchain_in_its_user_agent() {
+        // agy 1.2.11 指向假服务器时抓到的原样；X-Goog-Api-Client 和 UA 相同。
+        let agy = "google-genai-sdk/1.71.0 gl-go/go1.28-20260721-RC03 cl/951519500 +3ebc191975 X:fieldtrack,boringcrypto,simd,mapsplitgroup";
+        assert_eq!(
+            client_hint(&h(&[
+                ("user-agent", agy),
+                ("x-goog-api-client", agy),
+                ("x-goog-api-key", "k"),
+            ])),
+            Some("antigravity-cli".into())
+        );
+        // 外面的人用 Go SDK 写的程序：同一个 UA 前缀，普通的 Go 版本号。不是 agy。
+        assert_eq!(
+            client_hint(&h(&[(
+                "user-agent",
+                "google-genai-sdk/1.71.0 gl-go/go1.25.1"
+            )])),
+            None
+        );
+    }
+
     #[test]
     fn an_unknown_client_is_none_rather_than_a_guess() {
         // 猜错比不猜更糟：观察窗口会因此宣布「已生效」。