README

anthropic.go

@@ -177,9 +177,13 @@ func webSearchTools(cfg *WebSearchConfig) []anthropic.BetaToolUnionParam {
 	tools := []anthropic.BetaToolUnionParam{{OfWebSearchTool20250305: search}}
 
 	if cfg.Fetch {
+		fetchAllowed := cfg.FetchAllowedDomains
+		if len(fetchAllowed) == 0 {
+			fetchAllowed = cfg.AllowedDomains
+		}
 		fetch := &anthropic.BetaWebFetchTool20250910Param{
-			AllowedDomains: cfg.AllowedDomains,
-			BlockedDomains: cfg.BlockedDomains,
+			AllowedDomains: fetchHosts(fetchAllowed),
+			BlockedDomains: fetchHosts(cfg.BlockedDomains),
 			Citations:      anthropic.BetaCitationsConfigParam{Enabled: param.NewOpt(true)},
 		}
 		if cfg.MaxUses > 0 {
@@ -193,6 +197,29 @@ func webSearchTools(cfg *WebSearchConfig) []anthropic.BetaToolUnionParam {
 	return tools
 }
 
+// fetchHosts strips any path from each domain entry. web_fetch matches on host
+// only, so a path-scoped entry (valid for web_search) would otherwise never match
+// any fetch URL. Search keeps the path-scoped entries; fetch gets host-only.
+func fetchHosts(entries []string) []string {
+	if len(entries) == 0 {
+		return nil
+	}
+	seen := make(map[string]bool, len(entries))
+	hosts := make([]string, 0, len(entries))
+	for _, e := range entries {
+		host := e
+		if i := strings.IndexByte(host, '/'); i >= 0 {
+			host = host[:i]
+		}
+		if host == "" || seen[host] {
+			continue
+		}
+		seen[host] = true
+		hosts = append(hosts, host)
+	}
+	return hosts
+}
+
 func buildUserContext(username, firstName, lastName string, isPremium bool, languageCode string, messageTime int) string {
 	name := strings.TrimSpace(firstName + " " + lastName)
 	if name == "" {