Let an AI agent send faxes on behalf of your users

const sendFaxTool = {
  name: "send_fax",
  description: "Send a fax via the mintfax API. Returns a fax ID for status tracking.",
  input_schema: {
    type: "object",
    properties: {
      to: {
        type: "string",
        description: "Recipient fax number in E.164 format, e.g. +12015550100"
      },
      file_url: {
        type: "string",
        description: "URL of the document to fax (PDF or TIFF)"
      },
      idempotency_key: {
        type: "string",
        description: "UUID to prevent duplicate submissions on retry"
      }
    },
    required: ["to", "file_url", "idempotency_key"]
  }
};

async function handleSendFax({ to, file_url, idempotency_key }) {
  const res = await fetch("https://api.mintfax.com/v1/fax", {
    method: "POST",
    headers: {
      Authorization: `Bearer ${process.env.MINTFAX_API_KEY}`,
      "Content-Type": "application/json",
      "Idempotency-Key": idempotency_key,
    },
    body: JSON.stringify({ to, file_url }),
  });

  const data = await res.json();

  if (!res.ok) {
    return {
      success: false,
      error: data.error,
      message: data.message,
      action: data.action,
      docs: data.docs,
      retryable: res.status === 503 || res.status === 429,
    };
  }

  return {
    success: true,
    fax_id: data.id,
    status: data.status,
  };
}

async function pollFaxStatus(faxId, maxAttempts = 10) {
  for (let i = 0; i < maxAttempts; i++) {
    const res = await fetch(
      `https://api.mintfax.com/v1/fax/${faxId}`,
      {
        headers: {
          Authorization: `Bearer ${process.env.MINTFAX_API_KEY}`,
        },
      }
    );
    const data = await res.json();

    if (data.status === "delivered" || data.status === "failed") {
      return data;
    }

    await new Promise((r) => setTimeout(r, 5000));
  }

  return { status: "polling_timeout" };
}