# cwi-verification-kit — CWI Trust Layer

> The CWI Trust Layer verification library — one zero-dependency JavaScript
> bundle that lets any agent or app verify CWI attestations, stamp claims with
> reproducible confidence intervals, and score agent trust without inventing
> numbers. "Verified or it didn't happen."

- Live demo: https://cumulativewebinc.github.io/cwi-verification-kit/
- CDN: https://cdn.jsdelivr.net/gh/CumulativeWebInc/cwi-verification-kit@main/dist/cwi-verification-kit.js
- Repo: https://github.com/CumulativeWebInc/cwi-verification-kit
- License: MIT. Zero dependencies. Works in Node >= 18 and any browser.

## What's inside

- Keccak-256, SHA-256, secp256k1 ECDSA recovery, EIP-712 hashing — pure JS, no deps
- EAS attestation verification: deterministic schema UID, EAS domain,
  uid = keccak256(signature), EIP-712 signer recovery, ABI payload decode,
  refUID chain, salted blob binding, signature/blob tamper negatives
- The Error Bar: stamps any claim with a seeded confidence interval, a
  provenance check, and a reproducibility record (JS port of CWI errorbar.py,
  byte-identical canonical output)
- Trust Verdict: deterministic, evidence-bound agent trust scoring — returns
  insufficient-data instead of inventing scores (JS port of the CWI Verdict
  Engine, byte-identical canonical output)

## Honest limits

- Byte-identical parity vs the Python references holds for the documented
  fixtures; cross-language float-lexical edge cases are documented in
  docs/PARITY.md (known divergences).
- 31/31 node tests green (test/: crypto, EAS verify, error bar, trust verdict).

## Machine-readable

- docs/API.md — full API reference
- docs/PARITY.md — parity report vs independent references (viem, CPython)
- docs/.well-known/agent-card.json — agent discovery card

© 2026 Cumulative Web Inc · hp@cumulativeweb.com