Polymarket MCP Server

Instructions

Implementation Reference

• src/tools/gamma/markets.ts:50-67 (handler)

  Tool handler for "get_market", which delegates to GammaApi.getMarket.

    async (args) => {
      if (!args.id && !args.slug) {
        return {
          content: [{ type: "text", text: "Error: Either id or slug is required" }],
          isError: true,
        };
      }
      try {
        const data = await gamma.getMarket(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/tools/gamma/markets.ts:44-48 (registration)

  Registration of the "get_market" tool in the Gamma markets toolset.

  "get_market",
  "Get a single Polymarket market by ID or slug. Returns full market details including outcomes, prices, volume, and liquidity.",
  {
    id: z.string().optional().describe("Market ID"),
    slug: z.string().optional().describe("Market slug"),

• src/api/gamma.ts:99-114 (handler)

  API method that fetches a single market by ID or slug from the Gamma API.

  async getMarket(params: { id?: string; slug?: string }): Promise<GammaMarket> {
    if (params.id) {
      return this.client.gamma<GammaMarket>(
        `/markets/${params.id}`,
        undefined,
        CACHE_TTLS.marketById,
      );
    }
    const results = await this.client.gamma<GammaMarket[]>("/markets", {
      slug: params.slug,
    });
    if (!results || results.length === 0) {
      throw new Error(`Market not found: ${params.slug}`);
    }
    return results[0];
  }