io.github.neubuotPublished by GitHub account neubuotv1.5.0Updated Oct 24, 2026
Proof of existence, names and chain data of the Doichain blockchain for AI agents
Remote MCP server for the Doichain blockchain: anchor SHA-256 hashes as tamper-evident timestamps and read names, blocks, transactions and addresses.
Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.
Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.
Read https://sourceweft.com/mcp/io.github.neubuot%2Fdoichain/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.Add this to your client's mcpServers config.
{
"mcpServers": {
"doichain": {
"type": "http",
"url": "https://doi-api.sendlabs.de/mcp"
}
}
}
Tamper-evident timestamps for your AI agent.
Prove that a document already existed at a given time: anchor its hash on the Doichain (proof of existence), verify proofs and read names, blocks and addresses.
One URL, no account, no API key, no installation.
[MCP Registry] [Endpoint] [CI] [License: MIT] [Python 3.11+] [MCP 2024-11-05 to 2026-07-28]
Quick start · Tools · How it works · Limits · Security · Tool reference · Self-hosting · Deutsch
Endpoint: https://doi-api.sendlabs.de/mcp · Streamable HTTP · stateless · no authentication required
The Doichain is a public blockchain with a built-in name-value store (a Namecoin descendant, merge-mined with Bitcoin). This server makes it usable for any agent that speaks the Model Context Protocol: Claude, ChatGPT, Cursor, VS Code Copilot and many more. Ask your agent in plain language, it picks the right tool itself:
"Anchor the hash of offer-2026.pdf on the Doichain." "Did this contract already exist before October 1?" "Are d/example or id/alice about to expire?" "How is the Doichain doing right now?"
Opening the endpoint in a browser shows the landing page with setup instructions.
Check with claude mcp list. Without --scope user the server only applies to the current project.
Doichain and paste https://doi-api.sendlabs.de/mcp.Custom connectors also work on the free plan (one connector). On Team and Enterprise an owner adds it in the organization settings.
Turn on Settings → Security and login → Developer mode, then create an app under Plugins → + with the URL above and authentication None. Developer mode is available on the web for Plus, Pro, Business, Enterprise and Education.
~/.cursor/mcp.json (all projects) or .cursor/mcp.json (one project):
.vscode/mcp.json:
Try it without an AI client using the MCP Inspector: npx @modelcontextprotocol/inspector, choose Streamable HTTP and enter the URL. A small Python example is in examples/check_proof.py.
All tools return structured JSON (structuredContent) and carry MCP tool annotations. Only anchor_proof is not read-only. Parameters, return fields and examples: docs/tools.md.
Only the hash, and optionally a public note or file name, goes on chain. A SHA-256 cannot be turned back into the document. Anyone can verify a proof later with check_proof or on verifile.it, and changing a single byte of the document produces a different hash.
What a proof shows, and for how long:
poe/<sha256> stays active for 36,000 blocks (about 250 days at ten minutes per block). After that anyone can register it again, with their own note and address. check_proof keeps reporting the first anchoring as the proof time and shows a later registration separately in latest_registration. anchor_proof does not register an expired hash again unless you ask for it with reanchor_expired, and search_names lists expired proofs with include_expired.Agents need access to the file to hash it (Claude Code, Cursor, VS Code). In a plain chat, Verifile is the easiest way: drop the file, it is hashed in the browser and anchored with one click.
Hosted chat apps (Claude on the web, ChatGPT) connect from their providers' data centers, so all their users share the quota of those addresses. For regular anchoring use a client that connects from your own machine (Claude Code, Cursor, VS Code) or ask DOI Labs for an own key. Anchoring pauses automatically when the operating balance of the node wallet falls below a reserve, reading keeps working.
hash_text sees a short text and forgets it immediately.anchor_proof, for which the REST API registers the name from the operator's wallet. It runs as a separate service under its own system user, without read access to the API's key file, and may only open local connections._untrusted together with a notice, and the server instructions tell agents to treat them as data only.Found a vulnerability? Please use private vulnerability reporting, see SECURITY.md.
POST /mcp for all MCP messages. GET /mcp from a browser returns the landing page, any other GET or HEAD returns 405 with Allow: POST (there is no server-to-client SSE stream in stateless mode).GET /mcp/health for monitoring.The MCP server is a thin, stateless layer over the Doichain REST API (interactive docs), which runs next to a full Doichain Core node. See docs/self-hosting.md to run your own instance.
Releases follow semantic versioning. Pushing a tag vX.Y.Z runs the tests and publishes server.json to the official MCP Registry via GitHub Actions (OIDC, no secrets). The tag, server.json and pyproject.toml must carry the same version. See CONTRIBUTING.md and CHANGELOG.md.
MIT © 2026 DOI Labs AG. The hosted endpoint is operated by DOI Labs, legal notice.
Source: README.md at commit b7c51f3
Doichain network status
Current state of the Doichain network as seen by the node behind this server: block height, sync state, time of the last block, fork check, node version, peers, mempool size and whether public anchoring is available.
Takes no parameters.
SHA-256 of a text
Compute the SHA-256 digest of a short text (UTF-8) on the server, for example to anchor a statement or a message with anchor_proof. The text is sent to the server but not stored or logged. For files and for confidential texts compute the hash locally instead (sha256sum file, or Get-FileHash -Algorithm SHA256).
textrequiredCheck a proof of existence
Check whether a SHA-256 hash is anchored on the Doichain (name poe/<sha256>) and since when. Returns status (confirmed, pending, expired, unknown) and at the top level block height, block time, transaction and links of the first anchoring, which is the proof time. If the name was updated later or registered again after it expired (possibly by someone else), that registration is reported separately in latest_registration with its own holder and record, which are not part of the original proof. A confirmed or expired proof shows that a document with exactly this hash existed no later than the block time, not who submitted it.
sha256requiredAnchor a proof of existence
Anchor a SHA-256 hash on the Doichain as a tamper-evident timestamp (proof of existence, name poe/<sha256>). Free for users, limited per IP address and day (see get_anchoring_quota). Confirms with the next block, usually within 10 minutes, then check_proof returns block height and time. If the hash is already anchored or pending, the existing proof is returned instead of creating a second one. If an earlier proof of the hash has expired, it stays valid and is returned with expired true. Nothing is registered unless reanchor_expired is true. Only the hash and the optional note and file name become public, never the document itself. The operator of this server pays for the name and holds it. The proof shows that a document with this hash existed no later than the block time, not who submitted it.
notesha256requiredfilenamereanchor_expiredRemaining anchoring quota
How many proofs can still be anchored today (UTC day) within the free public quota for the caller's IP address. Hosted chat apps connect from their own servers, so their users share one quota. Callers that send their own API key in the X-API-Key header have no quota.
Takes no parameters.
Look up a Doichain name
Read the current value, owner address and expiry of a Doichain name. Unregistered names come back with exists false and status not_registered (the name is free). Expired names have status expired and the real expiry date.
namerequiredHistory of a Doichain name
All registrations and updates of a name, newest first: block height, transaction, owner address and the value at that time. Shows who held a name when, and every value it ever had.
namerequiredlimitCheck when names expire
Check up to 25 names at once: status (active, expiring_soon, expired, not_registered), blocks left, an estimated expiry date for active names (from the measured block interval) and the real expiry date for expired names. Names expire 36,000 blocks after their last update and are renewed by updating them from the owning wallet.
namesrequiredwarn_daysSearch names by prefix
List names that start with a prefix, in the node's order (shorter names first, then byte order). Lists only active names unless include_expired is true. Expired names (for example old poe/ proofs) stay in the chain history and are listed with include_expired. Page through large results with next_after until exhausted is true. Names and values are chosen by arbitrary users (name_untrusted, value_untrusted).
afterlimitprefixrequiredinclude_expiredGet a block
Header data of a block by height or hash: time, confirmations, number of transactions and the first 50 transaction IDs.
blockrequiredGet a transaction
A transaction with confirmations, block time, outputs (amount in DOI and address) and any name operation (name_doi, name_update, ...) it contains.
txidrequiredAddress balance and history
Confirmed and unconfirmed balance of a Doichain address in DOI, optionally with its most recent transactions. Invalid addresses return an error with the reason.
addressrequiredhistory_limitinclude_historyVerify a signed message
Check whether a message was signed with the private key of a Doichain address (signmessage format). Only legacy addresses (M... or N...) can sign messages, bech32 addresses (dc1q...) are not supported. Useful to confirm that a statement really comes from the holder of an address.
addressrequiredmessagerequiredsignaturerequired100% of the applicable checks met
How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.
claude mcp add --scope user --transport http doichain https://doi-api.sendlabs.de/mcp{ "mcpServers": { "doichain": { "url": "https://doi-api.sendlabs.de/mcp" } }}{ "servers": { "doichain": { "type": "http", "url": "https://doi-api.sendlabs.de/mcp" } }}sequenceDiagram participant U as You participant A as AI agent participant M as Doichain MCP server participant D as Doichain U->>A: "Anchor offer-2026.pdf" A->>A: sha256sum offer-2026.pdf (the file never leaves your machine) A->>M: anchor_proof(sha256) M->>D: name_doi poe/<sha256> = {"v":1,"alg":"sha256",...} D-->>M: transaction id (pending) M-->>A: txid, verify URL Note over D: next block, usually within 10 minutes U->>A: "Did this document exist before October 1?" A->>M: check_proof(sha256) M->>D: name_show / name_history M-->>A: confirmed, block 433,335, 2026-09-25 23:21 UTCAI agent ──HTTPS──▶ nginx ──▶ doichain-mcp (this repo, 127.0.0.1:8081) │ REST calls only, client IP passed on for the quota ▼ Doichain REST API (127.0.0.1:8080) ──▶ Doichain Core v31.1.6 + ElectrumXpython -m venv .venv. .venv/bin/activate # Windows: .venv\Scripts\activatepip install -e ".[dev]"pytest -q # offline tests, the REST API is mockedruff check .
# run locally against the public REST API (reading works, anchoring needs your own key)
[](https://doi-api.sendlabs.de/seal/github/neubuot/doichain-mcp)DOI_MCP_API_URL=https://doi-api.sendlabs.de python -m doichain_mcpnpx @modelcontextprotocol/inspector # connect to http://127.0.0.1:8081/mcp