Test it live
Run this flow in ZapSign Builders — the interactive REST API playground. Open in Builders →
Quick summary
| Criterion | MCP server | REST API |
|---|---|---|
| Who uses it | AI agents (Claude, ChatGPT, Cursor…) | Your app, backend, automations |
| Interface | Typed tools + natural language | HTTP (POST /api/v1/docs/, etc.) |
| Auth | ZAPSIGN_API_KEY on the MCP server | Authorization: Bearer <api_token> |
| Deploy | Remote URL (mcp.zapsign.com.br) or local stdio | Direct calls to api.zapsign.com.br |
| Best for | AI prototyping, conversational flows, assisted dev | Production product, webhooks, fine control |
When to use MCP
- You want an AI assistant to create documents, signers, and webhooks by conversation.
- You are exploring the API without writing code — the agent discovers tools automatically.
- You use Claude Desktop, ChatGPT (connector), Cursor, Codex, or Gemini CLI with
mcp-server-zapsign.
When to use REST API
- You embed e-signature into your product (SaaS, CRM, ERP).
- You need reliable webhooks (
POST /api/v1/user/company/webhook/) and retry control. - You want official SDKs (TypeScript, Java, Go) documented at docs.zapsign.com.br.
Using both
Teams often start with MCP to validate AI flows and move critical endpoints to REST in the backend. The MCP server calls the same API — nothing stops you from using both on the same ZapSign account (with separate workspace tokens).