Verify a capsule

Anyone holding a capsule or receipt can verify it — in the browser, on the command line, or as a library. Every path runs the same open-source verifier and checks the same two things: the signature and the inclusion proof.

In the browser

The fastest way to check a single receipt or signed statement is the hosted verifier. Paste a receipt or statement (and a key, if you want the signature checked) and read the verdict and reasons. It is stateless — nothing you submit is stored.

On the command line

pip install agent-action-capsule
agent-action-capsule verify --store ledger.jsonl

As a library

from scitt_cose import verify_receipt

r = verify_receipt(receipt, leaf_entry_hex=leaf,
                   log_public_key_pem=log_key)
print(r.ok)   # -> True

What a pass means

• The signature is intact and made by the stated issuer key.
• The leaf digest is provably included in the log at the proven tree size.
• Optionally, the log has stayed append-only between two tree heads (consistency).

For the mechanics of each check, see how verification works.