diff --git a/internal/auth/antigravity/auth.go b/internal/auth/antigravity/auth.go
index 12d112c4..8d3b216f 100644
--- a/internal/auth/antigravity/auth.go
+++ b/internal/auth/antigravity/auth.go
@@ -123,6 +123,7 @@ func (o *AntigravityAuth) FetchUserInfo(ctx context.Context, accessToken string)
 		return "", fmt.Errorf("antigravity userinfo: create request: %w", err)
 	}
 	req.Header.Set("Authorization", "Bearer "+accessToken)
+	req.Header.Set("User-Agent", o.loadCodeAssistUserAgent())
 
 	resp, errDo := o.httpClient.Do(req)
 	if errDo != nil {
@@ -180,7 +181,7 @@ func (o *AntigravityAuth) FetchProjectID(ctx context.Context, accessToken string
 	req.Header.Set("Authorization", "Bearer "+accessToken)
 	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("User-Agent", userAgent)
-	req.Header.Set("X-Goog-Api-Client", "gl-node/22.21.1")
+	req.Header.Set("X-Goog-Api-Client", misc.AntigravityGoogAPIClientUA)
 
 	resp, errDo := o.httpClient.Do(req)
 	if errDo != nil {
@@ -249,12 +250,13 @@ func (o *AntigravityAuth) FetchProjectID(ctx context.Context, accessToken string
 // OnboardUser attempts to fetch the project ID via onboardUser by polling for completion
 func (o *AntigravityAuth) OnboardUser(ctx context.Context, accessToken, tierID string) (string, error) {
 	log.Infof("Antigravity: onboarding user with tier: %s", tierID)
+	userAgent := o.loadCodeAssistUserAgent()
 	requestBody := map[string]any{
 		"tierId": tierID,
 		"metadata": map[string]string{
-			"ideType":    "ANTIGRAVITY",
-			"platform":   "PLATFORM_UNSPECIFIED",
-			"pluginType": "GEMINI",
+			"ide_type":    "ANTIGRAVITY",
+			"ide_version": misc.AntigravityVersionFromUserAgent(userAgent),
+			"ide_name":    "antigravity",
 		},
 	}
 
@@ -282,9 +284,8 @@ func (o *AntigravityAuth) OnboardUser(ctx context.Context, accessToken, tierID s
 		}
 		req.Header.Set("Authorization", "Bearer "+accessToken)
 		req.Header.Set("Content-Type", "application/json")
-		req.Header.Set("User-Agent", o.loadCodeAssistUserAgent())
-		req.Header.Set("X-Goog-Api-Client", APIClient)
-		req.Header.Set("Client-Metadata", ClientMetadata)
+		req.Header.Set("User-Agent", userAgent)
+		req.Header.Set("X-Goog-Api-Client", misc.AntigravityGoogAPIClientUA)
 
 		resp, errDo := o.httpClient.Do(req)
 		if errDo != nil {
diff --git a/internal/auth/antigravity/constants.go b/internal/auth/antigravity/constants.go
index 680c8e3c..61e73697 100644
--- a/internal/auth/antigravity/constants.go
+++ b/internal/auth/antigravity/constants.go
@@ -21,14 +21,11 @@ var Scopes = []string{
 const (
 	TokenEndpoint    = "https://oauth2.googleapis.com/token"
 	AuthEndpoint     = "https://accounts.google.com/o/oauth2/v2/auth"
-	UserInfoEndpoint = "https://www.googleapis.com/oauth2/v1/userinfo?alt=json"
+	UserInfoEndpoint = "https://www.googleapis.com/oauth2/v2/userinfo?alt=json"
 )
 
 // Antigravity API configuration
 const (
-	APIEndpoint    = "https://cloudcode-pa.googleapis.com"
-	APIVersion     = "v1internal"
-	APIUserAgent   = "google-api-nodejs-client/9.15.1"
-	APIClient      = "google-cloud-sdk vscode_cloudshelleditor/0.1"
-	ClientMetadata = `{"ideType":"IDE_UNSPECIFIED","platform":"PLATFORM_UNSPECIFIED","pluginType":"GEMINI"}`
+	APIEndpoint = "https://cloudcode-pa.googleapis.com"
+	APIVersion  = "v1internal"
 )
diff --git a/internal/misc/antigravity_version.go b/internal/misc/antigravity_version.go
index 1f05073e..0d187c25 100644
--- a/internal/misc/antigravity_version.go
+++ b/internal/misc/antigravity_version.go
@@ -20,6 +20,7 @@ const (
 	antigravityVersionCacheTTL = 6 * time.Hour
 	antigravityFetchTimeout    = 10 * time.Second
 	AntigravityNodeAPIClientUA = "google-api-nodejs-client/10.3.0"
+	AntigravityGoogAPIClientUA = "gl-node/22.21.1"
 )
 
 type antigravityRelease struct {
diff --git a/internal/runtime/executor/antigravity_executor.go b/internal/runtime/executor/antigravity_executor.go
index 3b3943b8..15d05a46 100644
--- a/internal/runtime/executor/antigravity_executor.go
+++ b/internal/runtime/executor/antigravity_executor.go
@@ -1785,7 +1785,7 @@ func (e *AntigravityExecutor) updateAntigravityCreditsBalance(ctx context.Contex
 	httpReq.Header.Set("Authorization", "Bearer "+token)
 	httpReq.Header.Set("Content-Type", "application/json")
 	httpReq.Header.Set("User-Agent", userAgent)
-	httpReq.Header.Set("X-Goog-Api-Client", "gl-node/22.21.1")
+	httpReq.Header.Set("X-Goog-Api-Client", misc.AntigravityGoogAPIClientUA)
 
 	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)
 	httpResp, errDo := httpClient.Do(httpReq)