Query DEX Pairs

Instructions

Implementation Reference

• src/tools/dex.ts:131-160 (handler)

  The async handler function that executes the 'query_dex_pairs' tool logic. Calls apiGet('/api/v1/dex/pairs') with optional chain, base_token, quote_token, and limit parameters, then formats the response.

    async ({ chain, base_token, quote_token, limit }) => {
      const res = await apiGet<DexQueryResponse>("/api/v1/dex/pairs", {
        chain,
        base_token,
        quote_token,
        limit: limit ?? 25,
      });
  
      if (!res.ok) {
        return {
          content: [
            {
              type: "text" as const,
              text: `API error (${res.status}): ${JSON.stringify(res.data)}`,
            },
          ],
          isError: true,
        };
      }
  
      const { count, data } = res.data;
      const warn = stalenessWarning(res);
      const summary = `${warn}Found ${count} DEX pair(s).`;
      const json = JSON.stringify(data, null, 2);
  
      return {
        content: [{ type: "text" as const, text: `${summary}\n\n${json}` }],
      };
    },
  );

• src/tools/dex.ts:103-130 (schema)

  Input schema for 'query_dex_pairs' using Zod. Defines optional parameters: chain (enum of chains), base_token, quote_token, and limit (1-100, default 25).

  {
    title: "Query DEX Pairs",
    description:
      "List available trading pairs on decentralized exchanges. Filter by chain, " +
      "base token, or quote token. Returns pair details with liquidity and volume. " +
      "Cost: $0.001 per query. Source: On-chain DEX analytics.",
    inputSchema: {
      chain: z
        .enum(["ethereum", "arbitrum", "polygon", "base", "bsc"])
        .optional()
        .describe("Filter by blockchain network"),
      base_token: z
        .string()
        .optional()
        .describe("Filter by base token symbol (e.g. WETH)"),
      quote_token: z
        .string()
        .optional()
        .describe("Filter by quote token symbol (e.g. USDC)"),
      limit: z
        .number()
        .int()
        .min(1)
        .max(100)
        .optional()
        .describe("Maximum results (default 25)"),
    },
  },

• src/tools/dex.ts:101-160 (registration)

  Registration of 'query_dex_pairs' tool via server.registerTool() with the tool name string 'query_dex_pairs', schema, and handler.

  server.registerTool(
    "query_dex_pairs",
    {
      title: "Query DEX Pairs",
      description:
        "List available trading pairs on decentralized exchanges. Filter by chain, " +
        "base token, or quote token. Returns pair details with liquidity and volume. " +
        "Cost: $0.001 per query. Source: On-chain DEX analytics.",
      inputSchema: {
        chain: z
          .enum(["ethereum", "arbitrum", "polygon", "base", "bsc"])
          .optional()
          .describe("Filter by blockchain network"),
        base_token: z
          .string()
          .optional()
          .describe("Filter by base token symbol (e.g. WETH)"),
        quote_token: z
          .string()
          .optional()
          .describe("Filter by quote token symbol (e.g. USDC)"),
        limit: z
          .number()
          .int()
          .min(1)
          .max(100)
          .optional()
          .describe("Maximum results (default 25)"),
      },
    },
    async ({ chain, base_token, quote_token, limit }) => {
      const res = await apiGet<DexQueryResponse>("/api/v1/dex/pairs", {
        chain,
        base_token,
        quote_token,
        limit: limit ?? 25,
      });
  
      if (!res.ok) {
        return {
          content: [
            {
              type: "text" as const,
              text: `API error (${res.status}): ${JSON.stringify(res.data)}`,
            },
          ],
          isError: true,
        };
      }
  
      const { count, data } = res.data;
      const warn = stalenessWarning(res);
      const summary = `${warn}Found ${count} DEX pair(s).`;
      const json = JSON.stringify(data, null, 2);
  
      return {
        content: [{ type: "text" as const, text: `${summary}\n\n${json}` }],
      };
    },
  );

• src/client.ts:35-41 (helper)

  stalenessWarning helper used by the handler to check for stale data headers.

  export function stalenessWarning(res: ApiResponse): string {
    if (!res.stale) return "";
    const parts = ["[STALE DATA]"];
    if (res.lastUpdated) parts.push(`Last updated: ${res.lastUpdated}`);
    if (res.ageSeconds != null) parts.push(`Age: ${res.ageSeconds}s`);
    return parts.join(" ") + "\n\n";
  }

• src/client.ts:44-76 (helper)

  apiGet helper used by the handler to make HTTP GET requests to the Verilex API.

  export async function apiGet<T = unknown>(
    path: string,
    params?: Record<string, string | number | undefined>,
  ): Promise<ApiResponse<T>> {
    const url = buildUrl(path, params);
  
    const headers: Record<string, string> = {
      Accept: "application/json",
      "User-Agent": "verilex-mcp-server/0.1.0",
    };
  
    // Forward x402 payment token if present in env (for paid endpoints)
    const paymentToken = process.env.VERILEX_PAYMENT_TOKEN;
    if (paymentToken) {
      headers["X-Payment-Token"] = paymentToken;
    }
  
    const res = await fetch(url, { headers });
    const data = (await res.json()) as T;
  
    const stale = res.headers.get("X-Data-Stale");
    const lastUpdated = res.headers.get("X-Data-Last-Updated");
    const ageSeconds = res.headers.get("X-Data-Age-Seconds");
  
    return {
      ok: res.ok,
      status: res.status,
      data,
      stale: stale === "true",
      lastUpdated: lastUpdated ?? undefined,
      ageSeconds: ageSeconds ? Number(ageSeconds) : undefined,
    };
  }