Sign, check and chain proof records for your AI agent.

# Call the tools by GET and POST, and fetch the skill with your settings. No key; nothing is stored.# A template for a type, then the hash to sign locally and the prev for the next record:curl -s "https://www.proof.md/api/v1/proof_template?type=action" | jq '{summary, claims_required}'curl -s https://www.proof.md/api/v1/canonical_hash \  -H 'content-type: application/json' \  -d '{"record":{"type":"custom","version":"1","subject":"note:1","claims":{"note":"hello"},"evidence":[],"actor":"agent:a","time":"2026-10-15T14:00:00Z","prev":null}}' \  | jq '{sha256, canonical}'# Verify a signed envelope you made with proof.mjs (public key only, never the private key)curl -s https://www.proof.md/api/v1/verify_proof -H 'content-type: application/json' \  -d "{\"record\": $(cat envelope.json)}" | jq '{summary, signature_valid, hash_matches, expired}'# The skill with your settings written in (approval proof above $250, keys rotated every 60 days)curl -s "https://www.proof.md/proof.md?preset=balanced&approval_over_usd=250&key_rotation_days=60" -D - -o SKILL.md | grep -i x-settings

// check-chain.mjs: verify a local chain file with the API and roll it up into a Merkle root. Run: node check-chain.mjs chain.jsonl// Sends only records, signatures and public keys. Keep the root it prints somewhere apart from the chain.import fs from "node:fs";const API = "https://www.proof.md/api/v1";const file = process.argv[2] ?? "chain.jsonl";const chain = fs.readFileSync(file, "utf8").split("\n").filter(Boolean).map((l) => JSON.parse(l));const post = async (tool, body) => {  const res = await fetch(`${API}/${tool}`, { method: "POST", headers: { "content-type": "application/json" }, body: JSON.stringify(body) });  const json = await res.json();  if (!res.ok) throw new Error(`${tool}: ${json.error} ${json.hint ?? ""}`);  return json;};// The API takes up to 200 records per call; check longer chains locally with: node proof.mjs chain chain.jsonlconst recent = chain.slice(-200);const report = await post("verify_chain", { records: recent });console.log(report.summary);for (const b of report.broken_links) console.log(`  broken link at #${b.index}: ${b.likely}`);const { root, summary } = await post("merkle_root", { hashes: recent.map((e) => e.hash), include_proofs: false });console.log(summary);fs.appendFileSync("roots.txt", `${new Date().toISOString()} ${recent.length} ${root}\n`);process.exit(report.all_ok ? 0 : 2);

// Call a tool over MCP (stateless JSON-RPC over HTTP POST): compare an action with a permission record.const res = await fetch("https://www.proof.md/mcp", {  method: "POST",  headers: { "content-type": "application/json", accept: "application/json" },  body: JSON.stringify({    jsonrpc: "2.0",    id: 1,    method: "tools/call",    params: {      name: "check_permission",      arguments: {        permission: {          type: "permission", version: "1", subject: "grant:billing-agent", evidence: [], actor: "user:owner",          time: "2026-10-01T00:00:00Z", prev: null,          claims: { grantor: "user:owner", grantee: "agent:billing-1", scope: ["invoices:pay"], not_after: "2026-12-31T23:59:59Z", max_amount: 500, currency: "USD" },        },        scope: "invoices:pay",        amount: 240,        currency: "USD",      },    },  }),});const { result } = await res.json();console.log(result.structuredContent.summary); // a comparison, not an authorization

// proof.mjs: the local command-line tool. Make keys, sign, verify, chain and roll up records offline. Node 18+, no dependencies.////   curl -fsSL https://www.proof.md/proof.mjs -o proof.mjs//   node proof.mjs keygen                          # proof-key.pem (private, stays here) + proof-key.pub.json//   node proof.mjs sign record.json --key proof-key.pem --chain chain.jsonl//   node proof.mjs verify envelope.json [--pub proof-key.pub.json] [--at 2026-10-15T15:00:00Z]//   node proof.mjs chain chain.jsonl [--pub proof-key.pub.json]//   node proof.mjs merkle chain.jsonl [--index 3]   # or: merkle --hashes h1,h2,h3//   node proof.mjs hash file1 file2 ...             # evidence entries [{ name, sha256 }]//// Format (version 1): record = { type, version: "1", subject, claims, evidence: [{ name, sha256 }],// actor, time, prev, expires? }. hash = SHA-256 of the canonical JSON (keys sorted, no whitespace).// The signature covers the same canonical bytes. Envelope = { record, hash, alg, key_id, public_key, signature }.//// A valid signature shows the record hasn't changed since it was signed and that the signer held// the key. It doesn't show the claims are true, and it isn't identity verification, notarization,// legal evidence or a compliance record. Use at your own risk; see https://www.proof.md/terms. MIT.//// Full source (10,307 bytes, no dependencies): https://www.proof.md/proof.mjs