@tempus1/x402-verify-cli

@tempus1/x402-verify-cli

Standalone verifier for x402 attestation receipts.

npx @tempus1/x402-verify-cli verify ./receipt.json
echo $?   # 0 = valid

Why a separate package

The point of a receipt is that a third party can check it without trusting the agent that produced it. Someone handing a receipt to an auditor should be able to say: this package only reads. It cannot write files, cannot pay for anything, cannot sign anything, and its entire network surface is one unauthenticated GET.

No API key. No Rubric account. No cooperation from the seller or the buyer.

Exit codes

exit	meaning
0	valid
1	hash mismatch — the record does not hash to its claimed leaf
2	proof mismatch — the proof does not reach the anchored root
3	not anchored — locally valid, but not on the ledger yet
4	fetch failed — the public verify endpoint could not be reached

3 and 4 are deliberately distinct from 1 and 2. A batch that has not flushed, and a verifier you cannot reach, are not the same thing as a forged receipt.

Options

--offline          hash and inclusion proof only; no network
--verify-url <url> override the endpoint recorded in the receipt
--timeout <ms>     anchor fetch timeout (default 15000)
--json             machine-readable output
--quiet            suppress human-readable output

Input may be a single receipt, a JSON array, or JSONL. With several, the exit code is the worst result across all of them.

What it checks

• sha256(jcs(callRecord)) equals the claimed leafHash. Pure local computation; catches any mutation of any byte of the record.
• Walking proof from that leaf reproduces root. Also purely local.
• GET /v1/verify/{attestationId} reports anchored and carries the same root.

Steps 1 and 2 run with --offline and need nothing but the file.

Library use

import { verifyReceipt, VERIFY_EXIT } from '@tempus1/x402-verify-cli';

const result = await verifyReceipt(receipt);
if (!result.ok) console.error(result.code, result.reason);

Also re-exports the primitives, so a verifier can be reimplemented against them in another language and checked for agreement: jcs, sha256Jcs, buildMerkleTree, computeRootFromProof, hashLeaf, hashNode, MERKLE_PARAMS.