APISign MCP Server

Name: APISign
Author: wes

Send documents out for legally binding e-signature, and manage the templates they come from, directly from an AI agent.

APISign runs a hosted Model Context Protocol server at https://apisign.io/mcp. There is nothing to install and nothing to self-host — point your client at the URL, give it an API key, and your agent can draft a contract from a template, fill its variables, send it to signers, and watch the signatures come in.

This repository holds the connection metadata and client configuration. The service itself lives at apisign.io.

Connect

1. Get an API key. Sign in at apisign.io, then go to Account → API Keys and create one. Copy it — it is shown once.

Pick the permission deliberately:

Permission	What the agent can do
Read Only	List and read templates and contracts. Nothing else.
Read & Write	Everything, including sending contracts, which charges your balance.

A Read Only key does not merely refuse the write tools — they are left out of the tools/list response entirely, so the agent never learns they exist. If your agent only needs to look things up, use one.

2. Add the server. The quickest route, which works for Claude, Cursor, ChatGPT and most other clients:

npx add-mcp https://apisign.io/mcp --header '{"x-api-key": "your-api-key-here"}'

Or configure it by hand:

{
  "mcpServers": {
    "apisign": {
      "url": "https://apisign.io/mcp",
      "headers": {
        "x-api-key": "your-api-key-here"
      }
    }
  }
}

Client	Config file
Claude Desktop (macOS)	`~/Library/Application Support/Claude/claude_desktop_config.json`
Claude Desktop (Windows)	`%APPDATA%\Claude\claude_desktop_config.json`
Cursor	`~/.cursor/mcp.json`, or `%USERPROFILE%\.cursor\mcp.json`
ChatGPT	Settings → Features → MCP servers → Add MCP server

Transport is Streamable HTTP. Authentication is the x-api-key header.

Tools

Twelve tools, in two families. Everything is scoped to the organization the API key belongs to.

Templates

Tool	Access	What it does
`template_list`	read	List all templates in the organization.
`template_get`	read	Fetch one template by ID, with its content and field definitions.
`template_create`	write	Create a blank template from a name and optional Markdown.
`template_update`	write	Change a template's name, content, or fields.
`template_upload`	write	Convert a base64-encoded DOCX/DOC into a template.
`template_archive`	write	Soft-delete a template.

Contracts

Tool	Access	What it does
`contract_list`	read	List contracts, optionally filtered by status.
`contract_get`	read	Fetch one contract, including every signer and their status.
`contract_create`	write	Create a contract from a template or from raw content, with signers.
`contract_update`	write	Edit a draft contract's details or signers. Drafts only.
`contract_send`	write	Send a contract for signing. Charges your balance and emails the signers.
`contract_cancel`	write	Cancel a draft or sent contract.

Templates are Markdown with Handlebars-style variables — {{client_name}}, {{effective_date}} — that contract_create fills in. Signature placeholders work the same way: a one-signer document needs a {{signature}}, and a multi-signer document gives each party their own, assigned through signer_fields.

A worked example

Draft an NDA for Acme Corp from our standard mutual NDA template, effective the first of next month, and send it to legal@acme.example and to me.

The agent calls template_list to find the template, template_get to read its variables, contract_create to fill them and attach both signers, then contract_send. You get back a contract ID you can follow with contract_get.

Discovery metadata

File	Consumed by
`server.json`	The official MCP registry — published as `io.apisign/apisign`.
`plugins/apisign/mcp.json`	Cursor and other Agent Plugins clients.
`glama.json`	Glama's indexer.

The server also serves its own card, without authentication, so directories can describe it without an API key:

https://apisign.io/.well-known/mcp.json
https://apisign.io/.well-known/mcp/server-card.json

Docs and support

MCP server documentation
API reference
Pricing — contracts are billed per document sent

Issues with the MCP integration are welcome here. Questions about your account belong at apisign.io.

License

MIT