| 1 | package tools |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "errors" |
| 6 | "fmt" |
| 7 | |
| 8 | mcplib "github.com/mark3labs/mcp-go/mcp" |
| 9 | "github.com/mark3labs/mcp-go/server" |
| 10 | |
| 11 | "github.com/mvanhorn/last30days-skill/mcp/internal/engine" |
| 12 | ) |
| 13 | |
| 14 | func registerPreflightTool(s *server.MCPServer, cfg Config) { |
| 15 | s.AddTool( |
| 16 | mcplib.NewTool("preflight", |
| 17 | mcplib.WithDescription( |
| 18 | "Safely summarize what last30days would read, write, execute, and contact "+ |
| 19 | "without running research, saving files, or reading browser cookies.", |
| 20 | ), |
| 21 | mcplib.WithString("format", mcplib.Description("Output shape: 'text' (default) for a concise summary or 'json' for structured details.")), |
| 22 | mcplib.WithReadOnlyHintAnnotation(true), |
| 23 | mcplib.WithDestructiveHintAnnotation(false), |
| 24 | mcplib.WithOpenWorldHintAnnotation(false), |
| 25 | ), |
| 26 | makePreflightHandler(cfg), |
| 27 | ) |
| 28 | } |
| 29 | |
| 30 | func makePreflightHandler(cfg Config) server.ToolHandlerFunc { |
| 31 | return func(ctx context.Context, req mcplib.CallToolRequest) (*mcplib.CallToolResult, error) { |
| 32 | format, err := preflightFormatArgument(req.GetArguments()) |
| 33 | if err != nil { |
| 34 | return mcplib.NewToolResultError(err.Error()), nil |
| 35 | } |
| 36 | |
| 37 | src, err := engine.EngineFS() |
| 38 | if err != nil { |
| 39 | return mcplib.NewToolResultError(fmt.Sprintf("engine source unavailable: %v", err)), nil |
| 40 | } |
| 41 | cacheDir, err := engine.EnsureUserCache(src, cfg.Version) |
| 42 | if err != nil { |
| 43 | return mcplib.NewToolResultError(fmt.Sprintf( |
| 44 | "engine extract failed: %v\nhint: set %s to a writable directory if the default cache location is locked down", |
| 45 | err, engine.CacheEnvOverride, |
| 46 | )), nil |
| 47 | } |
| 48 | |
| 49 | res, runErr := engine.Run(ctx, engine.RunOptions{ |
| 50 | CacheDir: cacheDir, |
| 51 | Args: preflightRunArgs(format), |
| 52 | }) |
| 53 | if runErr != nil { |
| 54 | return mcplib.NewToolResultError(formatRunError(runErr, res)), nil |
| 55 | } |
| 56 | return mcplib.NewToolResultText(string(res.Stdout)), nil |
| 57 | } |
| 58 | } |
| 59 | |
| 60 | func preflightRunArgs(format string) []string { |
| 61 | runArgs := []string{"--preflight", "--preflight-report-on-save-dir", mcpSaveDir()} |
| 62 | if format == "json" { |
| 63 | runArgs = append(runArgs, "--emit=json") |
| 64 | } |
| 65 | return runArgs |
| 66 | } |
| 67 | |
| 68 | func preflightFormatArgument(args map[string]any) (string, error) { |
| 69 | raw, ok := args["format"] |
| 70 | if !ok { |
| 71 | return "text", nil |
| 72 | } |
| 73 | value, ok := raw.(string) |
| 74 | if !ok { |
| 75 | return "", errors.New("format must be a string") |
| 76 | } |
| 77 | switch value { |
| 78 | case "", "text": |
| 79 | return "text", nil |
| 80 | case "json": |
| 81 | return "json", nil |
| 82 | default: |
| 83 | return "", fmt.Errorf("format must be 'text' or 'json', got %q", value) |
| 84 | } |
| 85 | } |
| 86 |