Holder Concentration

Instructions

Implementation Reference

• src/tools/holders.ts:108-132 (handler)

  Handler function for holder_concentration tool. Calls GET /api/v1/holders/{token}/concentration and returns the distribution metrics JSON.

  async ({ token, chain }) => {
    const res = await apiGet<{ dataset: string; data: Record<string, unknown> }>(
      `/api/v1/holders/${encodeURIComponent(token)}/concentration`,
      { chain },
    );
  
    if (!res.ok) {
      return {
        content: [
          {
            type: "text" as const,
            text: `API error (${res.status}): ${JSON.stringify(res.data)}`,
          },
        ],
        isError: true,
      };
    }
  
    const warn = stalenessWarning(res);
    return {
      content: [
        { type: "text" as const, text: `${warn}${JSON.stringify(res.data.data, null, 2)}` },
      ],
    };
  },

• src/tools/holders.ts:98-106 (schema)

  Input schema for holder_concentration: token (string, required) and chain (enum, optional, defaults to ethereum).

  inputSchema: {
    token: z
      .string()
      .describe("Token contract address"),
    chain: z
      .enum(["ethereum", "arbitrum", "polygon", "base", "bsc"])
      .optional()
      .describe("Blockchain network (default: ethereum)"),
  },

• src/tools/holders.ts:90-133 (registration)

  Registration of holder_concentration tool on the MCP server via server.registerTool().

  server.registerTool(
    "holder_concentration",
    {
      title: "Holder Concentration",
      description:
        "Get Gini coefficient and distribution metrics for a token. Shows concentration " +
        "risk, top-10/top-50 holder percentages, and supply distribution buckets. " +
        "Cost: $0.02 per query. Source: On-chain token analytics.",
      inputSchema: {
        token: z
          .string()
          .describe("Token contract address"),
        chain: z
          .enum(["ethereum", "arbitrum", "polygon", "base", "bsc"])
          .optional()
          .describe("Blockchain network (default: ethereum)"),
      },
    },
    async ({ token, chain }) => {
      const res = await apiGet<{ dataset: string; data: Record<string, unknown> }>(
        `/api/v1/holders/${encodeURIComponent(token)}/concentration`,
        { chain },
      );
  
      if (!res.ok) {
        return {
          content: [
            {
              type: "text" as const,
              text: `API error (${res.status}): ${JSON.stringify(res.data)}`,
            },
          ],
          isError: true,
        };
      }
  
      const warn = stalenessWarning(res);
      return {
        content: [
          { type: "text" as const, text: `${warn}${JSON.stringify(res.data.data, null, 2)}` },
        ],
      };
    },
  );

• src/index.ts:51-51 (registration)

  Top-level registration call that wires registerHolderTools into the MCP server.

  registerHolderTools(server);

• src/client.ts:44-76 (helper)

  Helper HTTP client function used by the handler to fetch concentration data from 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,
    };
  }