Detox MCP

Instructions

Implementation Reference

• src/tools/index.ts:153-176 (handler)

  Complete definition of the detox_init tool, including its handler function that executes the Detox 'init' CLI command with optional testRunner argument.

  export const initTool: Tool = {
    name: "detox_init",
    description: "Initialize Detox in a React Native project. Creates e2e folder structure and configuration.",
    inputSchema: zodToJsonSchema(InitArgsSchema),
    handler: async (args: z.infer<typeof InitArgsSchema>) => {
      const parsed = InitArgsSchema.parse(args);
      const cliArgs: string[] = ["init"];
  
      if (parsed.testRunner) {
        cliArgs.push("-r", parsed.testRunner);
      }
  
      const result = await executeDetoxCommand(cliArgs, { cwd: parsed.projectPath });
  
      return {
        success: result.success,
        output: result.stdout,
        errors: result.stderr,
        message: result.success
          ? "Detox initialized successfully. Check the e2e folder for test files."
          : "Failed to initialize Detox.",
      };
    },
  };

• src/utils/validators.ts:38-43 (schema)

  Zod input schema for detox_init tool defining projectPath (required) and testRunner (optional, defaults to 'jest').

  export const InitArgsSchema = z.object({
    projectPath: z.string().describe("Path to React Native project root"),
    testRunner: z.enum(["jest", "mocha"]).optional().default("jest"),
  });
  
  export type InitArgs = z.infer<typeof InitArgsSchema>;

• src/tools/index.ts:432-432 (registration)

  The detox_init tool (initTool) is registered by inclusion in the allTools export array used by the MCP server.

  initTool,

• src/index.ts:40-48 (registration)

  MCP ListTools handler that registers all tools including detox_init by mapping from allTools.

  server.setRequestHandler(ListToolsRequestSchema, async () => {
    return {
      tools: allTools.map((tool) => ({
        name: tool.name,
        description: tool.description,
        inputSchema: tool.inputSchema,
      })),
    };
  });

• src/index.ts:50-94 (registration)

  MCP CallTool handler that dispatches to the specific tool handler (including detox_init) found by name in allTools.

  server.setRequestHandler(CallToolRequestSchema, async (request) => {
    const { name, arguments: args } = request.params;
  
    const tool = allTools.find((t) => t.name === name);
    if (!tool) {
      throw new McpError(ErrorCode.MethodNotFound, `Unknown tool: ${name}`);
    }
  
    try {
      // Add project path to args if not specified
      const argsWithPath = {
        ...args,
        cwd: (args as any)?.cwd || PROJECT_PATH,
        projectPath: (args as any)?.projectPath || PROJECT_PATH,
      };
  
      const result = await tool.handler(argsWithPath);
  
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(result, null, 2),
          },
        ],
      };
    } catch (error: any) {
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(
              {
                success: false,
                error: error.message,
              },
              null,
              2
            ),
          },
        ],
        isError: true,
      };
    }
  });