Polymarket MCP Server

Instructions

Implementation Reference

• src/tools/gamma/markets.ts:30-40 (handler)

  The handler for the 'get_markets' tool which calls the Gamma API.

  async (args) => {
    try {
      const data = await gamma.getMarkets(args);
      return { content: [{ type: "text", text: JSON.stringify(data, null, 2) }] };
    } catch (error) {
      return {
        content: [{ type: "text", text: `Error: ${(error as Error).message}` }],
        isError: true,
      };
    }
  },

• src/api/gamma.ts:57-97 (handler)

  The actual implementation of the getMarkets API method.

  async getMarkets(params?: {
    limit?: number;
    offset?: number;
    order?: string;
    ascending?: boolean;
    slug?: string;
    tag?: string;
    closed?: boolean;
    active?: boolean;
    liquidity_min?: number;
    liquidity_max?: number;
    volume_min?: number;
    volume_max?: number;
    start_date_min?: string;
    start_date_max?: string;
    end_date_min?: string;
    end_date_max?: string;
  }): Promise<GammaMarket[]> {
    const query: Record<string, string | undefined> = {};
    if (params?.limit !== undefined) query.limit = String(params.limit);
    if (params?.offset !== undefined) query.offset = String(params.offset);
    if (params?.order) query.order = params.order;
    if (params?.ascending !== undefined) query.ascending = String(params.ascending);
    if (params?.slug) query.slug = params.slug;
    if (params?.tag) query.tag = params.tag;
    if (params?.closed !== undefined) query.closed = String(params.closed);
    if (params?.active !== undefined) query.active = String(params.active);
    if (params?.liquidity_min !== undefined)
      query.liquidity_num_min = String(params.liquidity_min);
    if (params?.liquidity_max !== undefined)
      query.liquidity_num_max = String(params.liquidity_max);
    if (params?.volume_min !== undefined)
      query.volume_num_min = String(params.volume_min);
    if (params?.volume_max !== undefined)
      query.volume_num_max = String(params.volume_max);
    if (params?.start_date_min) query.start_date_min = params.start_date_min;
    if (params?.start_date_max) query.start_date_max = params.start_date_max;
    if (params?.end_date_min) query.end_date_min = params.end_date_min;
    if (params?.end_date_max) query.end_date_max = params.end_date_max;
    return this.client.gamma<GammaMarket[]>("/markets", query);
  }

• src/tools/gamma/markets.ts:6-41 (registration)

  The MCP tool registration for 'get_markets'.

  server.tool(
    "get_markets",
    "List and filter Polymarket prediction markets. Supports rich filtering by volume, liquidity, dates, tags, and status. Sort by volume descending to find the most active markets.",
    {
      limit: z.number().min(1).max(100).default(20).describe("Number of results"),
      offset: z.number().min(0).default(0).describe("Pagination offset"),
      order: z
        .string()
        .optional()
        .describe("Sort field: volume, liquidity, startDate, endDate, createdAt"),
      ascending: z.boolean().optional().describe("Sort ascending (default: false)"),
      slug: z.string().optional().describe("Filter by market slug"),
      tag: z.string().optional().describe("Filter by tag label (e.g. 'politics', 'crypto')"),
      closed: z.boolean().optional().describe("Filter by closed status"),
      active: z.boolean().optional().describe("Filter by active status"),
      liquidity_min: z.number().optional().describe("Minimum liquidity (USD)"),
      liquidity_max: z.number().optional().describe("Maximum liquidity (USD)"),
      volume_min: z.number().optional().describe("Minimum volume (USD)"),
      volume_max: z.number().optional().describe("Maximum volume (USD)"),
      start_date_min: z.string().optional().describe("Minimum start date (ISO format)"),
      start_date_max: z.string().optional().describe("Maximum start date (ISO format)"),
      end_date_min: z.string().optional().describe("Minimum end date (ISO format)"),
      end_date_max: z.string().optional().describe("Maximum end date (ISO format)"),
    },
    async (args) => {
      try {
        const data = await gamma.getMarkets(args);
        return { content: [{ type: "text", text: JSON.stringify(data, null, 2) }] };
      } catch (error) {
        return {
          content: [{ type: "text", text: `Error: ${(error as Error).message}` }],
          isError: true,
        };
      }
    },
  );