> ## Documentation Index
> Fetch the complete documentation index at: https://docs.atlaswork.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# MCP server

> The signing lifecycle as a tool set for AI agents.

Atlas exposes a Model Context Protocol (MCP) server so AI agents can run the
entire signing lifecycle through tool calls. This is the **defining Atlas
workflow**: a user tells their assistant "send this NDA to Alice for signature,"
and the agent handles it end to end — agents prepare, humans approve.

<Note>
  Atlas MCP is a hosted Streamable HTTP server built with `mcp-use` on Manufact. Signing domain
  logic remains in the Atlas REST API.
</Note>

## Why MCP

The MCP server turns signing into a small, carefully designed tool set with the
properties agents need:

* **Review-first by default** — the agent prepares an envelope and returns a
  review URL; a human clicks Send. (Trusted template sends may auto-send.)
* **Idempotent writes** — a retried tool call cannot double-create or
  double-send. See [Idempotency](/guides/idempotency).
* **One-call sends** — provide the document and the parties in a single call.
* **Upload sessions** — when the agent's host can't transmit files, Atlas returns
  a short-lived upload link; the user drops the file there and the agent
  completes the session.

## Endpoint & auth

|              |                                                     |
| ------------ | --------------------------------------------------- |
| **Endpoint** | `https://mcp.atlaswork.ai/mcp`                      |
| **Protocol** | MCP Streamable HTTP                                 |
| **Auth**     | OAuth 2.1 with PKCE and dynamic client registration |

MCP clients authenticate with an **OAuth 2.1 access token** issued by Atlas.
API keys remain available for the [REST API](/guides/authentication#api-keys),
but are not entered into the hosted MCP connector.

Manufact handles initialization, protocol discovery, sessions, and the
authentication challenge. Every Atlas tool call requires a valid token.

## Connecting via OAuth

MCP clients that support OAuth discover and connect automatically — point the
client at the MCP endpoint and it walks the standard flow:

1. **Discover** — the 401 `WWW-Authenticate` points at
   `/.well-known/oauth-protected-resource`, which names the authorization server
   (`/.well-known/oauth-authorization-server`).
2. **Register** — dynamic client registration (RFC 7591) at
   `POST /api/auth/oauth2/register`.
3. **Authorize** — the user signs in and approves scopes (authorization code +
   PKCE); confidential clients may also use `client_credentials`.
4. **Call tools** — the client sends the access token to
   `https://mcp.atlaswork.ai/mcp`; Manufact verifies it and calls Atlas's scoped
   agent API.

Scopes: `envelopes:read`, `envelopes:write`, `documents:write`, `extract:read`.
Read tools require `envelopes:read`; write tools require `envelopes:write`.

The MCP server publishes protected-resource discovery at its hosted origin.
Atlas publishes authorization-server metadata from `app.atlaswork.ai`.

<Card title="Transport details" icon="plug" href="/mcp/transport">
  Request and response envelopes, error codes, and a working example.
</Card>

<Card title="Tool suite" icon="wrench" href="/mcp/tools">
  The tools available today and the full signing tool set being built out.
</Card>