feat: implement parallel_fetch tool for concurrent web page retrieval

pkg/agent/loop.go

@@ -52,7 +52,9 @@ func NewAgentLoop(cfg *config.Config, msgBus *bus.MessageBus, provider providers
 
 	braveAPIKey := cfg.Tools.Web.Search.APIKey
 	toolsRegistry.Register(tools.NewWebSearchTool(braveAPIKey, cfg.Tools.Web.Search.MaxResults))
-	toolsRegistry.Register(tools.NewWebFetchTool(50000))
+	webFetchTool := tools.NewWebFetchTool(50000)
+	toolsRegistry.Register(webFetchTool)
+	toolsRegistry.Register(tools.NewParallelFetchTool(webFetchTool))
 
 	// Register message tool
 	messageTool := tools.NewMessageTool()

pkg/tools/parallel_fetch.go

@@ -0,0 +1,76 @@
+package tools
+
+import (
+	"context"
+	"fmt"
+	"sync"
+)
+
+type ParallelFetchTool struct {
+	fetcher *WebFetchTool
+}
+
+func NewParallelFetchTool(fetcher *WebFetchTool) *ParallelFetchTool {
+	return &ParallelFetchTool{fetcher: fetcher}
+}
+
+func (t *ParallelFetchTool) Name() string {
+	return "parallel_fetch"
+}
+
+func (t *ParallelFetchTool) Description() string {
+	return "Fetch multiple URLs concurrently. Useful for comparing information across different sites or gathering diverse sources quickly."
+}
+
+func (t *ParallelFetchTool) Parameters() map[string]interface{} {
+	return map[string]interface{}{
+		"type": "object",
+		"properties": map[string]interface{}{
+			"urls": map[string]interface{}{
+				"type": "array",
+				"items": map[string]interface{}{
+					"type": "string",
+				},
+				"description": "List of URLs to fetch",
+			},
+		},
+		"required": []string{"urls"},
+	}
+}
+
+func (t *ParallelFetchTool) Execute(ctx context.Context, args map[string]interface{}) (string, error) {
+	urlsRaw, ok := args["urls"].([]interface{})
+	if !ok {
+		return "", fmt.Errorf("urls must be an array")
+	}
+
+	results := make([]string, len(urlsRaw))
+	var wg sync.WaitGroup
+
+	for i, u := range urlsRaw {
+		urlStr, ok := u.(string)
+		if !ok {
+			continue
+		}
+
+		wg.Add(1)
+		go func(index int, url string) {
+			defer wg.Done()
+			res, err := t.fetcher.Execute(ctx, map[string]interface{}{"url": url})
+			if err != nil {
+				results[index] = fmt.Sprintf("Error fetching %s: %v", url, err)
+			} else {
+				results[index] = res
+			}
+		}(i, urlStr)
+	}
+
+	wg.Wait()
+
+	var output string
+	for i, res := range results {
+		output += fmt.Sprintf("=== Result %d ===\n%s\n\n", i+1, res)
+	}
+
+	return output, nil
+}