Test it live

Run this flow in ZapSign Builders — the interactive REST API playground. Open in Builders →

Prerequisites

Why a URL? Unlike Claude Desktop and Cursor, ChatGPT does not run local MCP servers via stdio — it consumes connectors by URL. ZapSign’s MCP server is already hosted at mcp.zapsign.com.br.

Path 1 — MCP connector via URL (recommended)

Generate your ZapSign API token

Open Settings → Integrations → API and copy the api_token.

Add the connector in ChatGPT

In ChatGPT: Settings → Apps & Connectors → Advanced → Developer mode (enable). Then Connectors → Create:

  • Name: ZapSign
  • MCP server URL:
ZapSign MCP server URLURL
https://mcp.zapsign.com.br/mcp

ChatGPT redirects to ZapSign’s authorization screen. Paste your api_token to finish.

Test in chat

Sample promptchat
Using the ZapSign connector, list my document templates
and create a test document named "ChatGPT test" from
PDF https://zapsign.s3.amazonaws.com/exemplo.pdf with
signer Your Name <you@company.com>.

Path 2 — Custom GPT with Actions

If you prefer not to use developer mode, create a custom GPT that calls the ZapSign API directly:

  1. In chatgpt.com → GPTs → Create, open Configure → Actions.
  2. Import/describe an OpenAPI schema — start with POST /api/v1/docs/ and GET /api/v1/docs/. See the official docs.
  3. In Authentication, choose API Key → Bearer and paste your api_token.
  4. Instruct the GPT: "You manage e-signature documents in ZapSign. Always confirm signer name and email before creating a document."

Careful when sharing the GPT: the token embedded in Actions grants access to your account. Keep the GPT private or use a dedicated workspace with minimal permissions.

Common issues

SymptomLikely cause and fix
Connector will not connectURL must be exactly https://mcp.zapsign.com.br/mcp — no trailing slash.
401 on toolsInvalid or expired token. Reconnect and enter a new token.
Timeout creating a documentSlow/inaccessible source PDF. Use a fast public URL or base64.

Next steps