Built for agents and the people who build them.
Usign ships a full MCP server, a Stripe-style REST API, and HMAC-signed webhooks. Connect it to Claude or any MCP-capable agent and start sending. Same primitives everywhere: workspaces, templates, merge fields, contracts, signers.
Three steps to your first contract.
Add the Usign MCP server to your agent and authenticate the workspace once.
Your agent reads the published templates and their merge fields automatically.
Draft, preview, then confirm send. The signer gets a clean link by email.
Every tool your agent gets.
The full agent surface, named in mono. Create is always a draft. Send is always explicit.
Create is always a draft. Send is always explicit.
create_contract and create_contracts_bulk never dispatch. Email goes out only on send_contract. An agent literally cannot fire a contract in a single call. Developers look for this guarantee, so we put it in the type system.
Every event chains.
Each lifecycle event fires an HMAC-signed webhook carrying your own external_reference, the ID you set when creating the contract. Match it on your side and route the event anywhere: a CRM, a queue, another agent.