Macroforge MCP Server

Instructions

Implementation Reference

• src/tools/index.ts:393-462 (handler)

  Implements the core logic for the macroforge-autofixer tool by invoking the native Macroforge expander synchronously, processing diagnostics, and returning structured JSON output.
  async function handleAutofixer(args: { code: string; filename?: string }) { const filename = args.filename || 'input.ts'; try { const macroforge = await importMacroforge(); if (!macroforge) { return { content: [ { type: 'text' as const, text: JSON.stringify({ diagnostics: [{ level: 'error', message: 'Native Macroforge bindings not available. Install @macroforge/core.', }], summary: { errors: 1, warnings: 0, info: 0 }, require_another_tool_call_after_fixing: false, }, null, 2), }, ], }; } const result = macroforge.expandSync(args.code, filename, {}); const diagnostics = result.diagnostics || []; const output: AutofixerResult = { diagnostics: diagnostics.map((d) => ({ level: normalizeLevel(d.level), message: d.message, location: d.span ? { line: d.span.start.line, column: d.span.start.column } : undefined, help: d.help || undefined, notes: d.notes && d.notes.length > 0 ? d.notes : undefined, })), summary: { errors: diagnostics.filter((d) => d.level === 'Error').length, warnings: diagnostics.filter((d) => d.level === 'Warning').length, info: diagnostics.filter((d) => d.level === 'Info').length, }, require_another_tool_call_after_fixing: diagnostics.some((d) => d.level === 'Error'), }; return { content: [ { type: 'text' as const, text: JSON.stringify(output, null, 2), }, ], }; } catch (error) { const message = error instanceof Error ? error.message : String(error); return { content: [ { type: 'text' as const, text: JSON.stringify({ diagnostics: [{ level: 'error', message: `Error during analysis: ${message}`, }], summary: { errors: 1, warnings: 0, info: 0 }, require_another_tool_call_after_fixing: false, }, null, 2), }, ], }; } }
• src/tools/index.ts:119-154 (registration)

  Registers the macroforge-autofixer tool with the MCP server in the listTools response, providing name, description, and input schema.
  { name: 'macroforge-autofixer', description: `Validates TypeScript code with @derive decorators using Macroforge's native validation. Returns structured JSON diagnostics with: - level: error | warning | info - message: What's wrong - location: Line and column number (when available) - help: Suggested fix (when available) - notes: Additional context (when available) - summary: Count of errors, warnings, and info messages This tool MUST be used before sending Macroforge code to the user. If require_another_tool_call_after_fixing is true, fix the issues and validate again. Detects: - Invalid/unknown macro names - Malformed @derive decorators - @serde validator issues (email, url, length, etc.) - Macro expansion failures - Syntax errors in generated code`, inputSchema: { type: 'object', properties: { code: { type: 'string', description: 'TypeScript code with @derive decorators to validate', }, filename: { type: 'string', description: 'Filename for the code (default: input.ts)', }, }, required: ['code'], }, },
• src/tools/index.ts:219-220 (registration)

  Dispatches incoming tool calls for macroforge-autofixer to the handleAutofixer function within the main tools/call handler switch statement.
  case 'macroforge-autofixer': return handleAutofixer(args as { code: string; filename?: string });
• src/tools/index.ts:797-819 (schema)

  Defines the TypeScript interface for the structured JSON output returned by the macroforge-autofixer handler.
  interface AutofixerResult { diagnostics: Array<{ /** Severity level: "error", "warning", or "info" */ level: string; /** Human-readable description of the issue */ message: string; /** Source location (line and column) if available */ location?: { line: number; column: number }; /** Suggested fix for the issue */ help?: string; /** Additional context or explanatory notes */ notes?: string[]; }>; /** Summary counts for quick overview */ summary: { errors: number; warnings: number; info: number; }; /** If true, client should fix issues and call autofixer again */ require_another_tool_call_after_fixing: boolean; }
• src/tools/index.ts:869-879 (helper)

  Helper function that dynamically loads the optional @macroforge/core native module used for code validation and expansion in the handler.
  async function importMacroforge(): Promise<MacroforgeModule | null> { try { // Dynamic import to avoid build-time errors when @macroforge/core is not installed // @ts-expect-error - dynamic import of optional dependency const mod = await import('@macroforge/core'); return mod as MacroforgeModule; } catch { // Package not installed - return null to indicate unavailability return null; } }