Xdebug MCP Server

Instructions

Implementation Reference

• src/tools/advanced.ts:152-181 (handler)

  The core handler implementation for the 'add_logpoint' MCP tool. Registers the tool, defines input schema with Zod, creates the logpoint via LogpointManager, and returns a JSON-formatted success response with logpoint details.

  server.tool(
    'add_logpoint',
    'Add a logpoint that logs messages without stopping execution. Use {varName} placeholders for variables.',
    {
      file: z.string().describe('File path'),
      line: z.number().int().describe('Line number'),
      message: z.string().describe("Message template with {var} placeholders (e.g., 'User {$userId} logged in')"),
      condition: z.string().optional().describe('Optional condition'),
    },
    async ({ file, line, message, condition }) => {
      const logpoint = ctx.logpointManager.createLogpoint(file, line, message, condition);
      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify({
              success: true,
              logpoint: {
                id: logpoint.id,
                file,
                line,
                message,
                condition,
              },
            }),
          },
        ],
      };
    }
  );

• src/tools/advanced.ts:155-160 (schema)

  Zod schema for input validation of the add_logpoint tool parameters.

  {
    file: z.string().describe('File path'),
    line: z.number().int().describe('Line number'),
    message: z.string().describe("Message template with {var} placeholders (e.g., 'User {$userId} logged in')"),
    condition: z.string().optional().describe('Optional condition'),
  },

• src/session/logpoint-manager.ts:52-73 (helper)

  Helper method in LogpointManager that creates, initializes, and stores a new Logpoint instance. Called by the tool handler.

  createLogpoint(
    file: string,
    line: number,
    message: string,
    condition?: string
  ): Logpoint {
    const id = `logpoint_${++this.logpointIdCounter}`;
    const logpoint: Logpoint = {
      id,
      file,
      line,
      message,
      condition,
      hitCount: 0,
      createdAt: new Date(),
      enabled: true,
      logHistory: [],
    };
    this.logpoints.set(id, logpoint);
    logger.debug(`Logpoint created: ${id} at ${file}:${line}`);
    return logpoint;
  }

• src/session/logpoint-manager.ts:10-22 (schema)

  TypeScript interface defining the Logpoint data structure used by the manager and tool.

  export interface Logpoint {
    id: string;
    breakpointId?: string;
    file: string;
    line: number;
    message: string;
    condition?: string;
    hitCount: number;
    lastHitAt?: Date;
    createdAt: Date;
    enabled: boolean;
    logHistory: LogEntry[];
  }

• src/tools/index.ts:61-61 (registration)

  Registration call to registerAdvancedTools function, which includes the add_logpoint tool registration, invoked from the main registerAllTools.

  registerAdvancedTools(server, ctx as AdvancedToolsContext);