claude-agent-contracts

A contract-signing agent in ~80 lines, built with the Claude Agent SDK and the eContract MCP server. Tell it in plain words what to send, to whom and where each person signs; it sends the contract, waits until the document is ready and hands you the signing links.

$ node agent.mjs "Send <PDF URL> to Alice <alice@example.com> (signs under PARTY A) and then Bob <bob@example.com> (signs under PARTY B). Give me their links."
→ send_contract {"title":"Service Agreement","fileUrl":"https://raw.githubusercontent.com/…","signers":[…]}
→ get_contract {"contractId":"0ed49013-…"}
→ get_signing_links {"contractId":"0ed49013-…"}
I sent the Service Agreement (contract CTR-20261017-27SPFE) for signature. No emails went out.
- Alice (alice@example.com), signs first under "PARTY A": https://econtract.online/sign/93700b…
- Bob (bob@example.com), signs second under "PARTY B": https://econtract.online/sign/f165aa…
Bob can sign only after Alice has signed.
(4 turns, 10.0 s)

Run it

Requirements: Node.js 18+, and Claude access for the Agent SDK (an ANTHROPIC_API_KEY, or a signed-in Claude Code on the same machine).

git clone https://github.com/contractlayer/claude-agent-contracts && cd claude-agent-contracts
npm install
export ECONTRACT_API_KEY=cl_live_...   # free account: econtract.online → Dashboard → API keys
npm start                              # sends the sample agreement to two example addresses (links only)
node agent.mjs "Which of my contracts are still waiting for signatures?"

How it is built

agent.mjs calls query() with:

• The eContract MCP server as a remote HTTP server: https://api.econtract.online/mcp with Authorization: Bearer <ECONTRACT_API_KEY>.
• Only eContract tools. tools: [] removes the built-in tools (shell, files, web); allowedTools lists the eContract tools the agent may call, and permissionMode: 'dontAsk' denies everything else instead of prompting.
• No cancelling by default. void_contract is added only with --allow-void. Without it the agent explains that it cannot cancel and links the contract in the app.
• A short system prompt: send with delivery: "link" unless asked for emails, pass "signs under …" as each signer's signatureAnchor, poll get_contract until the document is ready.

Signing always stays with people: no eContract tool can sign or decline, each signer signs through their own link after confirming a code sent to their email.

What the eContract tools do here

Tool	Used for
send_contract	Create the contract from a PDF/DOCX (base64, public URL or template) and send it; signatureAnchor places each signature below a text in the document
get_contract, list_contracts	Readiness, status, who signed
get_signing_links, send_reminder	Personal links (no email), reminders to pending signers
download_signed_document, get_audit_trail	The signed PDF and the signing evidence
void_contract	Cancel (only with --allow-void)

More

• Connect the same server to Claude, ChatGPT, Cursor and other clients: contractlayer/contractlayer → mcp
• The same operations over REST (Node.js, Python): contractlayer/contract-manager
• MCP reference: developers.econtract.online/docs/mcp

License

MIT