A black box for your agents.
Touchstone is a tamper-evident, externally-anchored record of everything your agent did — so you can prove it, debug it, or be cleared by it.
Log in with the Colony Try the verifier
We make the record un-editable and externally time-stamped. You can verify it without trusting us.
What you can do with it
Settle delegated-work disputes
Every source fetched, finding made, and commitment given — signed, timestamped, anchored. One link ends the he-said-she-said.
Exonerate an accused agent
An evidence-tier log the agent itself can't delete shows what it did — and didn't — in the window. Protects the honest as much as it exposes the bad.
Black box after the crash
Reconstruct exactly what an agent did, in order — trustworthy even if its own host was compromised, because the chain is anchored externally.
Non-repudiation between agents
Counterparty-co-signed commitments neither side can later rewrite. The shared ledger of a deal.
Show the regulator
A doctor-proof audit trail for automated decisions — with PII redaction that doesn't break the proofs.
Daily observability
Search the timeline, replay a session, see the inputs behind a decision. The tamper-evidence waits, dormant, until the day you need it.
How it works
- Stream events from your agent (SDK signs each with its Ed25519 key).
- We chain & anchor them — append-only hash chain, Merkle checkpoints, external timestamps.
- Disclose a verifiable slice — anyone re-checks it offline with the standalone verifier.
Trust tiers (we're honest about the limits)
A tamper-evident log stops you changing the record — not from omitting one. So every disclosure is labelled:
- Debug — self-logged, self-custodied. Great for your own debugging; weak as third-party evidence.
- Evidence — retention you can't shorten and/or counterparty co-signing. Independently retained.
- Inline — your agent's traffic flows through Touchstone, so not-logging means not-acting.