How to Give a Vercel AI SDK Agent B2B Data (REST Tools and MCP)

npm install ai zod @ai-sdk/mcp
npm install -D tsx typescript
export LEADOCEAN_API_KEY="..."   # from app.leadocean.io
export AI_GATEWAY_API_KEY="..."  # or your provider's key

const BASE_URL = "https://api.leadocean.io";

export const budget = { limit: 25, spent: 0 };

export class LeadOceanError extends Error {}

const sleep = (s: number) => new Promise((r) => setTimeout(r, s * 1000));

export async function call(
  method: "GET" | "POST",
  path: string,
  opts: { query?: Record<string, string>; body?: unknown } = {},
) {
  const url = new URL(path, BASE_URL);
  for (const [k, v] of Object.entries(opts.query ?? {})) url.searchParams.set(k, v);

  let res: Response | undefined;
  for (let attempt = 0; attempt < 3; attempt++) {
    res = await fetch(url, {
      method,
      headers: {
        "x-api-key": process.env.LEADOCEAN_API_KEY!,
        "content-type": "application/json",
      },
      body: opts.body ? JSON.stringify(opts.body) : undefined,
    });
    const wait = Number(res.headers.get("Retry-After") ?? "1");
    if (res.status === 429 && wait <= 5) { await sleep(wait); continue; }
    if (res.status === 503) { await sleep(2 ** attempt); continue; }
    break;
  }
  const r = res!;

  if (r.status === 200) {
    const body = await r.json();
    budget.spent += body?.meta?.credits ?? 0;
    return body;
  }
  if (r.status === 404) return { found: false }; // nobody matched, costs nothing

  const text = await r.text();
  if (r.status === 400)
    throw new LeadOceanError(`Rejected: ${text}. Check enum values with listValues.`);
  if (r.status === 402)
    throw new LeadOceanError("Out of records on the Free plan. Stop and tell the user.");
  if (r.status === 429)
    throw new LeadOceanError("Rate limited. Do not retry now. Tell the user.");
  throw new LeadOceanError(`LeadOcean returned ${r.status}: ${text}`);
}

import { ToolLoopAgent, isStepCount, tool } from "ai";
import { z } from "zod";
import { budget, call } from "./leadocean";

const left = () => budget.limit - budget.spent;

const listValues = tool({
  description:
    "Free. Exact values for a filter: job_level, job_function, country, seniority, industry.",
  inputSchema: z.object({ name: z.string(), q: z.string().optional() }),
  execute: async ({ name, q }) => {
    const body = await call("GET", `/v1/enums/${name}`, {
      query: { limit: "50", ...(q ? { q } : {}) },
    });
    return body.data;
  },
});

const countPeople = tool({
  description:
    'Free. Size a segment. Values are comma-separated, e.g. {"jobLevel": "VP", "country": "CA"}.',
  inputSchema: z.object({ filters: z.record(z.string(), z.string()) }),
  execute: async ({ filters }) => {
    const body = await call("GET", "/v1/people/search", {
      query: { ...filters, count: "true", limit: "1" },
    });
    return body.meta.total as number;
  },
});

const trim = (row: any) => {
  const contact = row.contact_data ?? {};
  const job = contact.contact_current_experiences?.[0] ?? {};
  return {
    person_id: row.meta?.source_ids?.person_id,
    name: row.profile_data?.profile_full_name,
    title: job.job_title,
    company: job.company_name,
    domain: job.company_domain,
    email_status: contact.email_status,
  };
};

const searchPeople = tool({
  description:
    "Costs 1 record per person returned. Returns thin rows: name, title, company, person_id.",
  inputSchema: z.object({
    filters: z.record(z.string(), z.array(z.string())),
    limit: z.number().int().min(1).max(25).default(5),
  }),
  execute: async ({ filters, limit }) => {
    if (left() <= 0) throw new Error("Record budget for this run is spent. Stop.");
    const body = await call("POST", "/v1/people/search", {
      body: { ...filters, limit: Math.min(limit, left()) },
    });
    return body.data.map(trim);
  },
});

const enrichPerson = tool({
  description:
    "Costs 1 record. Returns the profile and revealed emails for one person_id.",
  inputSchema: z.object({ personId: z.string() }),
  execute: async ({ personId }) => {
    if (left() < 1) throw new Error("Record budget for this run is spent. Stop.");
    const body = await call("POST", "/v1/people/enrich", {
      body: { person_id: personId, reveal_email: true },
    });
    return body.data ?? body;
  },
});

const agent = new ToolLoopAgent({
  model: "anthropic/claude-sonnet-5.5",
  instructions:
    "You build small B2B prospect lists with LeadOcean. Always call countPeople first. " +
    "Search only when the count is under 100,000. Enrich at most 3 people, and only when " +
    "asked for contact details. Look up enum values with listValues instead of guessing.",
  tools: { listValues, countPeople, searchPeople, enrichPerson },
  stopWhen: isStepCount(12),
});

const result = await agent.generate({
  prompt: "Find 5 VPs of Sales in Canada and tell me how many exist in total.",
});
console.log(result.text);
console.log(`LeadOcean records spent: ${budget.spent}`);

npx tsx agent.ts

import { ToolLoopAgent } from "ai";
import { createMCPClient } from "@ai-sdk/mcp";

const mcpClient = await createMCPClient({
  transport: {
    type: "http",
    url: "https://api.leadocean.io/mcp",
    authProvider: myOAuthClientProvider, // your OAuthClientProvider implementation
  },
});

try {
  const agent = new ToolLoopAgent({
    model: "anthropic/claude-sonnet-5.5",
    tools: await mcpClient.tools(),
  });
  const result = await agent.generate({
    prompt: "Count VPs of Sales in Canada. Do not search.",
  });
  console.log(result.text);
} finally {
  await mcpClient.close();
}

{"name":"job_level","total":6,"values":["C-Team","Director","Manager","Other","Staff","VP"]}

{
  "success": true,
  "data": [
    {
      "profile_data": { "profile_full_name": "Jane Doe" },
      "contact_data": {
        "has_email": true,
        "email_status": "verified",
        "contact_current_experiences": [
          { "job_title": "VP Sales", "company_name": "Acme", "company_domain": "acme.com" }
        ]
      },
      "meta": { "source_ids": { "person_id": "12345678" } }
    }
  ],
  "meta": { "count": 1, "limit": 5, "credits": 1, "nextCursor": "..." }
}