Trailproof = Trail + Proof. Every event is cryptographically chained — tamper one, and the entire chain proves it.
Why Trailproof?
AI agents make autonomous decisions — approving requests, writing to memory, calling external APIs. Regulators (EU AI Act Article 19) and customers increasingly demand proof that these actions were logged faithfully and that nothing was altered after the fact. Traditional logging can’t provide that guarantee.The Trailproof Pipeline
Every event flows through a validation, hashing, optional signing, and append-only storage pipeline. Verification walks the chain backwards to check integrity.Core Pillars
Tamper-Evident Chain
SHA-256 hash chain links every event to the previous one. Modify event 5 in a chain of 100 — events 5 through 100 all fail verification. You can’t silently tamper with history.
Dual SDK Parity
Native libraries for Python and TypeScript with identical behavior. Same canonical JSON algorithm, same genesis hash, same test vectors. Emit in Python, verify in TypeScript.
Zero Dependencies
Stdlib-only in Python (
hashlib, json, uuid), Node.js built-ins only in TypeScript (crypto, fs). No supply chain risk from your audit trail.HMAC Signing
Optional HMAC-SHA256 signatures prove event provenance — that events were created by the holder of a specific secret key. Uses timing-safe comparison to prevent timing attacks.
Quick Example
The 10-Field Event Envelope
Next Steps
Quickstart
Install and emit your first event in 5 minutes.
Event Envelope
Deep dive into the 10-field event structure.
Hash Chain
How events are cryptographically linked.
API Reference
Full API documentation for both SDKs.