diff --git a/cmd/debug.go b/cmd/debug.go
index 2948edc..d121a10 100644
--- a/cmd/debug.go
+++ b/cmd/debug.go
@@ -132,7 +132,7 @@ func runDebugMetaAds(cmd *cobra.Command, args []string) error {
 		body["ad_account_id"] = debugMetaAdAccountID
 	}
 
-	c := client.NewREST(getWebAPIURL(), token)
+	c := client.NewREST(getWebAPIURL(), token, Version)
 	result, err := c.Post("/api/debug/meta-ads", body)
 	if err != nil {
 		return fmt.Errorf("debug query failed: %w", err)
diff --git a/cmd/dynamic.go b/cmd/dynamic.go
index a21c29d..4317d77 100644
--- a/cmd/dynamic.go
+++ b/cmd/dynamic.go
@@ -79,7 +79,7 @@ func maybeAutoRefresh(cache *ToolsCache) {
 func runAutoRefresh(baseURL, token string) error {
 	cache, _ := loadToolsCache()
 
-	hashResult, err := client.FetchToolsHash(baseURL)
+	hashResult, err := client.FetchToolsHash(baseURL, Version)
 	if err != nil {
 		return err
 	}
diff --git a/cmd/refresh.go b/cmd/refresh.go
index adaffcd..c5701ba 100644
--- a/cmd/refresh.go
+++ b/cmd/refresh.go
@@ -89,7 +89,7 @@ func fetchAndCacheTools(baseURL, token string, verbose bool) (*ToolsCache, error
 	}
 
 	// Fetch and store the current hash
-	if hashResult, err := client.FetchToolsHash(baseURL); err == nil {
+	if hashResult, err := client.FetchToolsHash(baseURL, Version); err == nil {
 		cache.Hash = hashResult.Hash
 	}
 
diff --git a/internal/client/mcp.go b/internal/client/mcp.go
index 7d56677..5da0ad5 100644
--- a/internal/client/mcp.go
+++ b/internal/client/mcp.go
@@ -179,8 +179,14 @@ type ToolsHashResult struct {
 // FetchToolsHash retrieves the combined tools hash from the server.
 // baseURL is the MCP base URL (e.g. https://mcp.pipeboard.co).
 // This endpoint requires no authentication.
-func FetchToolsHash(baseURL string) (*ToolsHashResult, error) {
-	resp, err := http.Get(baseURL + "/api/tools-hash")
+func FetchToolsHash(baseURL, version string) (*ToolsHashResult, error) {
+	req, err := http.NewRequest("GET", baseURL+"/api/tools-hash", nil)
+	if err != nil {
+		return nil, fmt.Errorf("creating request: %w", err)
+	}
+	req.Header.Set("User-Agent", "pipeboard-cli/"+version)
+
+	resp, err := http.DefaultClient.Do(req)
 	if err != nil {
 		return nil, fmt.Errorf("fetching tools hash: %w", err)
 	}
diff --git a/internal/client/rest.go b/internal/client/rest.go
index 1f39625..b23d108 100644
--- a/internal/client/rest.go
+++ b/internal/client/rest.go
@@ -12,14 +12,16 @@ import (
 type RESTClient struct {
 	baseURL    string
 	token      string
+	userAgent  string
 	httpClient *http.Client
 }
 
-// NewREST creates a REST API client.
-func NewREST(baseURL, token string) *RESTClient {
+// NewREST creates a REST API client. version is used in the User-Agent header.
+func NewREST(baseURL, token, version string) *RESTClient {
 	return &RESTClient{
 		baseURL:    baseURL,
 		token:      token,
+		userAgent:  "pipeboard-cli/" + version,
 		httpClient: &http.Client{},
 	}
 }
@@ -39,6 +41,7 @@ func (c *RESTClient) Post(path string, body interface{}) (map[string]interface{}
 
 	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("Authorization", "Bearer "+c.token)
+	req.Header.Set("User-Agent", c.userAgent)
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {