BA | Stamp MCP server
Give an AI agent the ability to prove a document existed at a point in time. The agent hashes the file locally and talks to BA | Stamp over the Model Context Protocol — the file itself never leaves the agent, only the SHA-256 hash.
Endpoint
Streamable-HTTP MCP endpoint (spec 2026-07-28):
https://bastamp.com/api/mcpPoint any MCP-capable client at this URL. Every tool acts on your account, so the endpoint requires authentication — see below.
Authentication
The endpoint requires a connected account; there are two ways to authenticate, and the server advertises OAuth so clients that support it offer a sign-in button automatically.
OAuth (recommended for connectors). When you add BA | Stamp as a custom connector in Claude.ai or ChatGPT, the client discovers our authorization server and opens a browser sign-in — no key to paste. Approve once and the connector stays linked; review and revoke linked apps at /account/connections.
API key (for scripts, CI and programmatic clients). Send your key as a bearer token:
Authorization: Bearer ba_live_<your key>Mint one at /account/api-keys (format ba_live_<32 hex>; shown once, store it safely). Each stamp_document call spends one credit — top up at /#pricing.
Tools
| Tool | Access | What it does |
|---|---|---|
| verify_document | read-only | Check whether a SHA-256 hash is timestamped and read its on-chain anchors (Polygon, Bitcoin, Ethereum when present). |
| stamp_document | 1 credit | Anchor a document hash on-chain. Consumes one stamp credit. The file never leaves the caller — pass only the SHA-256. |
| get_stamp | read-only | Your account's record for a hash: file label plus anchor status. |
| list_stamps | read-only | Your recent stamps, newest first, with status and anchor summary. |
| get_account | read-only | Your account id, email and remaining stamp-credit balance. |
Anchoring is asynchronous
stamp_document returns pending: the on-chain anchor lands at the next batch (Polygon within minutes, Bitcoin via OpenTimestamps later). Call verify_document or get_stamp afterwards to read the anchor, or subscribe to the stamp.anchored webhook. See the REST API reference for webhooks, batch stamping and the certificate/forensic-packet endpoints.
Operated by Aletheia Tech Ltd, London, UK. · API reference