Package Exports

@proofslip/mcp-server

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@proofslip/mcp-server

MCP server for ProofSlip — receipt-based verification for AI agent workflows. Create, verify, and poll ephemeral receipts that let agents prove what happened before deciding what happens next.

Tools

`create_receipt`

Create a receipt to record that something happened. Receipts expire after 24 hours by default.

Parameter	Type	Required	Description
`type`	enum	Yes	`action`, `approval`, `handshake`, `resume`, `failure`
`status`	string	Yes	Freeform status (e.g. "success", "pending", "failed")
`summary`	string	Yes	What happened — max 280 chars
`payload`	object	No	Structured JSON data (max 4KB)
`ref`	object	No	Workflow references (run_id, agent_id, workflow_id, etc.)
`expires_in`	number	No	TTL in seconds (60–86400, default 24h)
`idempotency_key`	string	No	Prevents duplicate receipts on retry
`audience`	"human"	No	Enrich verify page with social cards

Requires: PROOFSLIP_API_KEY environment variable.

`verify_receipt`

Verify a receipt and retrieve its full data before deciding what to do next.

Parameter	Type	Required	Description
`receipt_id`	string	Yes	The receipt ID (starts with `rct_`)

No API key required.

`check_receipt_status`

Lightweight status poll — returns only status and polling guidance, no payload.

Parameter	Type	Required	Description
`receipt_id`	string	Yes	The receipt ID (starts with `rct_`)

No API key required. Use this instead of verify_receipt when you only need to know if state has changed.

`signup`

Get a free API key (500 receipts/month).

Parameter	Type	Required	Description
`email`	string	Yes	Your email address

No API key required.

Usage Example

You: "Create a receipt proving we sent the welcome email"

Agent calls create_receipt:
  type: "action"
  status: "success"
  summary: "Sent welcome email to user@example.com"
  ref: { workflow_id: "onboarding-123", agent_id: "email-agent" }

→ Returns receipt_id, verify_url, is_terminal: true

You: "Verify receipt rct_abc123 before sending the follow-up"

Agent calls verify_receipt:
  receipt_id: "rct_abc123"

→ Returns full receipt: type, status, summary, payload, ref
→ Agent confirms the action happened before proceeding

You: "Check if the approval is still pending"

Agent calls check_receipt_status:
  receipt_id: "rct_def456"

→ Returns: status: "pending", is_terminal: false, next_poll_after_seconds: 30
→ Agent waits 30s then checks again

Setup

Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "proofslip": {
      "command": "npx",
      "args": ["-y", "@proofslip/mcp-server"],
      "env": {
        "PROOFSLIP_API_KEY": "ak_your_key_here"
      }
    }
  }
}

Cursor / Windsurf

Add to MCP settings:

{
  "mcpServers": {
    "proofslip": {
      "command": "npx",
      "args": ["-y", "@proofslip/mcp-server"],
      "env": {
        "PROOFSLIP_API_KEY": "ak_your_key_here"
      }
    }
  }
}

Claude Code

claude mcp add proofslip -- npx -y @proofslip/mcp-server

Then set your API key in your environment or .env file.

Configuration

Variable	Required	Description
`PROOFSLIP_API_KEY`	For creating receipts	Your API key (starts with `ak_`)
`PROOFSLIP_BASE_URL`	No	API base URL (default: `https://proofslip.ai`)

Get an API Key

Use the signup tool from any MCP client, or:

curl -X POST https://proofslip.ai/v1/auth/signup \
  -H "Content-Type: application/json" \
  -d '{"email": "you@example.com", "source": "api"}'

License

MIT

JSPM