APEX PSI

APEX PSI MCP server

Apex PSI is not a tool and not a product. It is the verification substrate — the layer beneath proof. It does not judge. It does not certify. It only remembers. This server is one application built on that layer.

One config line gives any MCP-capable agent (Claude, Cursor, Qoder, Cline, Windsurf, and the rest) five evidence tools: seal, verify, anchor, cite, verify_chain.

A seal records the SHA-256 hash of a decision, document or artefact in a public append-only ledger and returns a receipt. Anyone can look that hash up again — free, forever, with no account, no key and no cooperation from us.

What a receipt proves: that this exact content existed at this timestamp, and has not changed since. What it never proves: that the content is true. A seal is an audit trail, not a verdict.

Tools

Tool	What it actually does
seal	Writes the record's SHA-256 hash to the ledger and returns a receipt carrying an Ed25519 signature over the Merkle leaf, an ML-DSA-65 post-quantum signature, and — when a slot is available — an LMS-W4-SHA256 signature. The receipt's own algorithm field states which of those it got.
verify	Looks a hash (or a whole receipt) up in the ledger and reports whether it is present and unchanged. Integrity, not truth.
anchor	Reads the Bitcoin/OpenTimestamps anchoring state of the ledger's pending Merkle roots. Pass action: "anchor" explicitly to request that pending roots be submitted — an anchor is confirmed only when a real block is found.
cite	Turns a receipt into a citation (APA, BibTeX, MLA) that points at a public, independently checkable record.
verify_chain	Recomputes each hash's presence and Merkle continuity across a chain of receipts. A recomputation result, not an opinion.

Install

Add to your MCP client config:

{
  "mcpServers": {
    "apex-psi": {
      "command": "npx",
      "args": ["-y", "apex-psi-mcp"]
    }
  }
}

Or locally: npm install apex-psi-mcp.

Prove it works in two minutes

1. Ask the agent: "Seal the sentence 'hello psi' with APEX PSI."
2. Take the decision_hash from the receipt and paste it into the public verifier: https://www.ai-governance-standard.com/verify

If the site returns the record, the seal is real. You never had to trust this server, our npm package, or our word — which is the entire point of the protocol.

Limits, stated plainly

Free use needs no account and no key: 20 operations per minute and 100 per day, enforced per server instance — a flood guard rather than a subscription quota. Above that, an API key raises the ceiling; capacity is priced, the finding never is. Verification itself is unlimited and free: running the verifier locally costs nothing at all — apex-psi-verifier on npm, psi-verifier on PyPI.

Configuration

Environment variables (both optional):

• APEX_API_BASE — override the notary endpoint. Default: https://qhtntebpcribjiwrdtdd.supabase.co/functions/v1
• APEX_API_KEY — raises the daily ceiling for a workload. Never required to seal or verify.

What this server does not do

• It does not store your content. Only the hash leaves your machine.
• It does not certify, grade, score or approve anything.
• It exposes no edit or delete path: the interface this server uses is write-once sealing plus read-only lookup. The check that matters is yours to run — re-verify any receipt at any time, and any change shows up as a failed lookup.
• It is not a legal opinion, and no court has agreed to accept a receipt in advance.

Links

• Protocol and standard: https://www.ai-governance-standard.com
• Public verifier: https://www.ai-governance-standard.com/verify
• Machine-readable summary for AI answers: https://www.ai-governance-standard.com/llms.txt
• npm: https://www.npmjs.com/package/apex-psi-mcp

License

MIT