Contracts.io

Solutions

Contracts for developers and agents.

The same verbs the app has, over an API and an MCP server. Draft a contract from a sentence or a template, import the documents you already hold, stage decisions, and let webhooks tell you when something moves. A person presses Send, every time.

For developers

What a developer, or an agent, can do here.

One verb set, two hands

Every button in the app is an endpoint, and every endpoint is a button. Draft from a prompt or a template with one call; import Word, PDF, text or Markdown with another. There is no envelope, no recipients list to configure and no routing order. The API is written down in full before it is built, and the docs say so on every page.

The API, from the start

It can never send or sign

A send, a reply or a signature without a person's confirmation comes back 409 confirmation_required, and no key, scope, flag or setting removes it. Over MCP there is no send verb to call, the return type has no success variant, and a runtime guard checks every send-class result.

The MCP server

Words move on unanimity

No call writes clause text. You propose; the words change when every required negotiator has accepted. Every write carries the hash of the words you read, and a contract that moved under you comes back words_changed rather than deciding against words you never saw.

The model underneath

Webhooks, and a question over the corpus

Deliveries are signed, sent at least once and deduplicated on the event id. Ask a question in English across everything the key can open, and the answer is its citations: contract, block, span and the quoted words.

Webhooks

The site is written for machines too

llms.txt lists every public page, llms-full.txt carries each page's own lead paragraph, the sitemap names every route, and robots.txt names the crawlers one by one.

llms.txt

Make one by hand first. The API has the same verbs.

The other side never pays and never makes an account.

Create contract

Last reviewed by the contracts.io editors. How these pages are written.