feat: implement tool registry and add various tools for HTTP, file operations, SSH, and Matrix messaging

tools/file.go

@@ -0,0 +1,69 @@
+package tools
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/enmanuel/agents/internal/config"
+)
+
+// NewReadFile creates a read_file tool that reads local files.
+// Validates paths against cfg.AllowedPaths when non-empty.
+func NewReadFile(cfg config.FileOpsCfg) Tool {
+	return Tool{
+		Def: Def{
+			Name:        "read_file",
+			Description: "Read the contents of a local file.",
+			Parameters: []Param{
+				{Name: "path", Type: "string", Description: "Absolute path to the file to read", Required: true},
+			},
+		},
+		Exec: func(ctx context.Context, args map[string]any) Result {
+			path := getString(args, "path")
+			if path == "" {
+				return Result{Err: fmt.Errorf("read_file: path is required")}
+			}
+
+			absPath, err := filepath.Abs(path)
+			if err != nil {
+				return Result{Err: fmt.Errorf("read_file: %w", err)}
+			}
+
+			if err := validatePath(absPath, cfg.AllowedPaths); err != nil {
+				return Result{Err: err}
+			}
+
+			data, err := os.ReadFile(absPath)
+			if err != nil {
+				return Result{Err: fmt.Errorf("read_file: %w", err)}
+			}
+
+			// Limit output to 64 KB
+			content := string(data)
+			if len(content) > 64*1024 {
+				content = content[:64*1024] + "\n... (truncated)"
+			}
+
+			return Result{Output: content}
+		},
+	}
+}
+
+func validatePath(absPath string, allowedPaths []string) error {
+	if len(allowedPaths) == 0 {
+		return nil
+	}
+	for _, allowed := range allowedPaths {
+		a, err := filepath.Abs(allowed)
+		if err != nil {
+			continue
+		}
+		if strings.HasPrefix(absPath, a) {
+			return nil
+		}
+	}
+	return fmt.Errorf("path %q not under any allowed path", absPath)
+}