Codex skill: Ed25519 witness manifest verification for a scaffolded harness.
What it does
Reads .harness/witness.json, validates the Ed25519 signature against the embedded public key, and reports VALID / INVALID with a one-line reason.
Distinct from validate-harness:
validate-harnessis the umbrella — doctor + verify + path-guard + mcp + secretsverify-witnessis only the signature check — fast yes/no for CI / federation handshakes / multi-signer workflows
Usage from Codex
/verify-witness
/verify-witness path=./my-harness
/verify-witness path=./my-harness strict=false
Equivalent CLI
harness verify ./my-harness
Why it's separate from validate-harness
When two harnesses federate (iter 9), they need to confirm each other's witness signatures BEFORE doing the full release-readiness check. Splitting this surface lets federation peers run a fast signature handshake without paying for the full validate sweep.
Also: CI workflows that only care about signature integrity (e.g. mirroring a published harness to a private registry) can call this skill instead of the heavier umbrella.
What's checked
| Check | Detail |
|---|---|
| File present | .harness/witness.json exists |
| Manifest shape | All required fields (harness, version, entries, public_key, signature) |
| Signature | Ed25519 verify against the embedded public key |
| Strict mode | If strict=true and no witness, exit non-zero. If false, soft-skip with PASS |
Exit 0 = signature VALID. Exit 1 = INVALID / missing (strict mode).