touchstone-verify 0.3.2

Independently verify a Touchstone disclosure — zero dependencies, pure Python.

touchstone-verify

Independently verify a Touchstone disclosure — in pure Python, with zero dependencies. Read it before you trust it: it's a small, self-contained file.

A disclosure is a tamper-evident slice of an agent's action log. This package re-derives, with no trust in Touchstone, that the slice is intact (entry hashes recompute), attributed (the subject's Ed25519 signature holds, epoch-aware across key rotation), and ordered (hash-chained, with checkpoints that are append-only, server-signed, and witness-co-signed). It also checks selective-disclosure field proofs and reports the external anchors. It proves tampering by anyone who is not Touchstone — it does not prove completeness, and says so.

It agrees byte-for-byte with the other two Touchstone verifiers (verify.php, verifier.js): all three are tested against the same conformance corpus.

Install

pip install touchstone-verify

Use

Command line — pass a file, a URL, or a disclosure token:

touchstone-verify https://touchstone.cv/d/833cd4ca23fbb940dd71843ca47a807e
touchstone-verify ./bundle.json
touchstone-verify 833cd4ca23fbb940dd71843ca47a807e        # fetches from touchstone.cv

Exit code 0 = verified, 1 = a load-bearing check failed, 2 = couldn't load.

Library:

from touchstone_verify import verify_disclosure
import json, urllib.request

bundle = json.load(urllib.request.urlopen("https://touchstone.cv/d/<token>"))
result = verify_disclosure(bundle)
print(result["ok"])           # True / False
for e in result["entries"]:
    for c in e["checks"]:
        print(c["ok"], c["msg"])

What it checks

• Integrity — every entry_hash recomputes from its fields.
• Attribution — the subject signature verifies over the canonical signed content; genesis proof-of-possession; key_rotation new-key PoP; counterparty co-signatures.
• Ordering — prev_hash chain linkage; Merkle inclusion in the cited checkpoint.
• Checkpoints — server signature over each Merkle root; append-only linkage between consecutive checkpoints; independent witness co-signatures.
• Selective disclosure — each revealed field proves Merkle inclusion in payload_hash; withheld fields never appear in the bundle.

For split-view / Bitcoin-anchor cross-checking across independent relays, see the companion gossip_check.py at https://touchstone.cv/gossip_check.py.

License

Apache-2.0.