WebSim MCP Server

Instructions

Implementation Reference

• server.js:629-641 (handler)

  The MCP tool handler for 'get_user_followers' that validates arguments using UserParamsSchema, fetches data via apiClient, and returns a standardized JSON response.

  handler: async (args) => {
    const { user, limit = 20, offset = 0 } = UserParamsSchema.parse(args);
    const result = await apiClient.getUserFollowers(user, limit, offset);
    return {
      content: [{
        type: "text",
        text: JSON.stringify({
          success: true,
          data: result,
          message: `Successfully retrieved ${result.items?.length || 0} followers of ${user}`
        }, null, 2)
      }]
    };

• server.js:609-627 (schema)

  Input schema definition for the 'get_user_followers' tool, specifying parameters user (required), limit, and offset with descriptions and defaults.

  inputSchema: {
    type: "object",
    properties: {
      user: {
        type: "string",
        description: "Username"
      },
      limit: {
        type: "number",
        description: "Number of users to return (default: 20)",
        default: 20
      },
      offset: {
        type: "number",
        description: "Number of users to skip (default: 0)",
        default: 0
      }
    },
    required: ["user"]

• server.js:159-162 (helper)

  Helper method in WebSimAPIClient class that constructs and sends HTTP request to retrieve followers for a given user from the WebSim API.

  async getUserFollowers(user, limit = 20, offset = 0) {
    const params = new URLSearchParams({ limit: limit.toString(), offset: offset.toString() });
    return this.makeRequest(`/api/v1/users/${user}/followers?${params}`);
  }

• server.js:37-39 (schema)

  Zod schema used for input validation in the 'get_user_followers' handler (and other user-related tools), requiring a 'user' string.

  const UserParamsSchema = z.object({
    user: z.string().describe('Username')
  });

• server.js:606-642 (registration)

  Full tool registration object added to the 'tools' array, which is used by the MCP server for tool listing and execution.

  {
    name: "get_user_followers",
    description: "Get followers of a specific WebSim user",
    inputSchema: {
      type: "object",
      properties: {
        user: {
          type: "string",
          description: "Username"
        },
        limit: {
          type: "number",
          description: "Number of users to return (default: 20)",
          default: 20
        },
        offset: {
          type: "number",
          description: "Number of users to skip (default: 0)",
          default: 0
        }
      },
      required: ["user"]
    },
    handler: async (args) => {
      const { user, limit = 20, offset = 0 } = UserParamsSchema.parse(args);
      const result = await apiClient.getUserFollowers(user, limit, offset);
      return {
        content: [{
          type: "text",
          text: JSON.stringify({
            success: true,
            data: result,
            message: `Successfully retrieved ${result.items?.length || 0} followers of ${user}`
          }, null, 2)
        }]
      };
    }