citesig

CiteSig is an open protocol for embedding cryptographic verification signatures inside factual claims — a trust layer for the AI era.

This package reserves the citesig name on PyPI. The canonical, machine-readable specification lives at github.com/citesig/spec.

Status

v0.0.1 is a namespace placeholder. No functional Python implementation is included in this release. Calling citesig.sign() or citesig.verify() will raise NotImplementedError with a pointer to the specification, so downstream code fails loudly instead of silently trusting an unimplemented stub.

The reference specification is at v0.1 — published September 2026. See the current specification.

What CiteSig does

CiteSig defines a compact, deterministic format for signing factual claims with Ed25519 signatures. A verifier can check that a claim was signed by an identifiable key at a specific time, without depending on any centralized service.

• Cryptographic, not statistical — a signed verdict, not a confidence score
• Deterministic canonicalization — JCS (RFC 8785) so signatures survive round-trips
• Provider-agnostic signers — did:key and https:// signer identities
• Compact form — single-line representation for embedding in HTML, JSON, or Markdown

Reference implementation roadmap

The Python reference implementation is planned but not yet published. When it lands, the public API will be:

from citesig import sign, verify

# Signing (planned — currently raises NotImplementedError)
signed_claim = sign(claim, private_key, signer_id)

# Verification (planned — currently raises NotImplementedError)
result = verify(signed_claim)  # -> {"ok": True/False, "signer": "...", "reason": "..."}

Test vectors and canonicalization rules for cross-language implementations are at github.com/citesig/spec/tree/main/test-vectors/v0.1.

Governance

CiteSig is authored under a neutral-protocol identity. DeepInquiry sponsors the initial spec drafting but does not own the protocol. See the main repository for governance details as they evolve.

License

• Specification prose (this package): CC-BY-4.0
• Code and test vectors (in the main repository): MIT

Links

• Website: citesig.org
• Specification repository: github.com/citesig/spec
• npm package: @citesig/spec
• Report issues: github.com/citesig/spec/issues