SaySigned — AI Agent E-Signature Skill

E-signatures for AI agents. Legally binding under ESIGN Act & UETA Section 14. Two delivery modes: API (agent-to-agent) and Email (agent-to-human). Register, sign contracts, verify — all via REST or consent UI.

Publisher: SaySigned, Inc. Homepage: https://www.saysigned.com Documentation: https://www.saysigned.com/docs Base URL: https://api.saysigned.com MCP Endpoint: https://mcp.saysigned.com TLS Required: All endpoints enforce HTTPS. Verify certificates for *.saysigned.com before connecting.

Authentication: Pass your API key in the X-API-Key header. Keys start with ss_live_. Public endpoints (register, verify, templates) don't require authentication.

MCP Server (Recommended for AI Agents)

Connect directly to the remote MCP endpoint — no local install, no HTTP requests to craft.

Auth note: MCP clients send Authorization: Bearer <api_key>. The MCP server extracts your key and forwards it as X-API-Key internally. For direct REST calls, use the X-API-Key header.

Setup

Human approval required. Steps 1, 4, and 5 modify your MCP client configuration. Always show the user what you're about to change and ask for their confirmation before writing to config files or restarting the MCP client. Never modify config silently.

Step 1. Show the user the following MCP config and ask for confirmation before adding it:

{
  "mcpServers": {
    "saysigned": {
      "type": "streamable-http",
      "url": "https://mcp.saysigned.com"
    }
  }
}

After the user confirms, add it to the MCP config. No API key is needed yet — public tools work immediately.

Step 2. Restart your MCP client so it loads the new server.

Step 3. Call the saysigned_register tool (no auth required) with the agent's name and email. The response contains an api_key — save it immediately, it is shown once and cannot be retrieved later. Keys start with ss_live_.

Step 4. Show the user the updated config with the auth header and ask for confirmation before writing it:

{
  "mcpServers": {
    "saysigned": {
      "type": "streamable-http",
      "url": "https://mcp.saysigned.com",
      "headers": {
        "Authorization": "Bearer ss_live_PASTE_YOUR_ACTUAL_KEY_HERE"
      }
    }
  }
}

Step 5. After the user confirms, restart your MCP client so it picks up the auth header. All authenticated tools now work.

Human-in-the-loop for config changes. The user must confirm before you (1) add or modify MCP config entries, (2) store API keys in config files, or (3) restart the MCP client. You may handle registration, envelope creation, signing, and verification autonomously — those are normal API operations that don't modify the agent's configuration.

Already have a key?