Epic: Proof of Causal Integrity v0.1 vertical slice

[safal207]

Goal

Build the first executable end-to-end vertical slice of Proof of Causal Integrity (PoCI) v0.1 inside ProofPath.

PoCI should determine whether a high-risk AI-agent action is supported by verifiable intent, authority, causal grounding, execution evidence, and independently checkable result evidence.

Product boundary

This epic covers a single-node reference implementation and conformance package. It does not include a token, blockchain, staking, governance, production key management, or claims of decentralization.

Target flow

signed human intent
  -> agent proposal
  -> authority and scope checks
  -> causal-parent validation
  -> execution receipt
  -> observed result
  -> witness verification
  -> ACCEPT / HOLD / BLOCK / CHALLENGE
  -> portable evidence bundle

Required artifacts

• PoCI v0.1 specification
• Action Proof Envelope JSON Schema
• deterministic canonicalization and hashing rules
• reference fixtures for valid and adversarial cases
• Python reference verifier
• automated conformance tests
• CI gate
• threat model
• runnable end-to-end demo
• integration map for CML, LTP/T-Trace, LiminalDB, and Ibex

Backlog and execution order

Phase 1 — Normative contract and security model

• P0: Specify PoCI v0.1 protocol and decision semantics #181 — Specify PoCI v0.1 protocol and decision semantics
• P0: Define Action Proof Envelope v0.1 JSON Schema #182 — Define Action Proof Envelope v0.1 JSON Schema
• P0: Specify deterministic canonicalization and evidence hashing #183 — Specify deterministic canonicalization and evidence hashing
• P0: Define PoCI threat model and challenge taxonomy #189 — Define PoCI threat model and challenge taxonomy

Phase 2 — Executable reference implementation

• P0: Add PoCI reference and adversarial fixture corpus #184 — Add PoCI reference and adversarial fixture corpus
• P0: Implement Python PoCI reference verifier #185 — Implement Python PoCI reference verifier
• P0: Build PoCI conformance and determinism test suite #187 — Build PoCI conformance and determinism test suite

Phase 3 — Reviewer-ready vertical slice

• P0: Add PoCI validation and cross-language checks to CI #188 — Add PoCI validation and cross-language checks to CI
• P0: Build runnable PoCI end-to-end evidence demo #190 — Build runnable PoCI end-to-end evidence demo

Phase 4 — Independent implementation and ecosystem adapters

• P1: Extend Rust verifier with PoCI envelope validation #186 — Extend Rust verifier with PoCI envelope validation
• P1: Map PoCI adapters to CML, LTP/T-Trace, LiminalDB, and Ibex #191 — Map PoCI adapters to CML, LTP/T-Trace, LiminalDB, and Ibex

Recommended PR slicing

1. PR 1 — Contract: P0: Specify PoCI v0.1 protocol and decision semantics #181, P0: Define Action Proof Envelope v0.1 JSON Schema #182, P0: Specify deterministic canonicalization and evidence hashing #183, first valid schema example.
2. PR 2 — Corpus: P0: Add PoCI reference and adversarial fixture corpus #184 and the initial threat-to-fixture mapping from P0: Define PoCI threat model and challenge taxonomy #189.
3. PR 3 — Reference verifier: P0: Implement Python PoCI reference verifier #185 and core tests from P0: Build PoCI conformance and determinism test suite #187.
4. PR 4 — Demo and CI: P0: Add PoCI validation and cross-language checks to CI #188 and P0: Build runnable PoCI end-to-end evidence demo #190.
5. PR 5 — Independent verification: P1: Extend Rust verifier with PoCI envelope validation #186.
6. PR 6 — Ecosystem adapters: P1: Map PoCI adapters to CML, LTP/T-Trace, LiminalDB, and Ibex #191.

Epic acceptance criteria

• A valid fixture returns ACCEPT deterministically.
• Missing or invalid authorization cannot return ACCEPT.
• Missing causal parent returns HOLD or BLOCK according to the profile.
• Scope violation returns BLOCK.
• Tampered execution or result evidence returns CHALLENGE or BLOCK.
• Re-running verification produces byte-stable normalized output.
• Evidence can be verified offline without the live gateway.
• Python and Rust produce the same golden evidence roots.
• All fixtures and tests run in CI.
• README contains a reviewer-friendly one-command quickstart.

Explicit non-goals for v0.1

• distributed consensus
• economic incentives or tokenomics
• GPU hardware identity
• TEE or zkML attestation
• production custody or wallets
• regulatory certification
• model truthfulness claims

Gate for creating a separate network repository

Do not create liminal-proof-network until at least one of these is demonstrated:

1. two independently operated witness processes interoperate;
2. an external repository consumes Action Proof Envelope;
3. dispute, discovery, or settlement logic no longer belongs in ProofPath;
4. network-specific release cadence becomes necessary.

[safal207]

Implementation started in draft PR #193.

Current PR slice:

• PoCI v0.1 normative semantics;
• Action Proof Envelope Draft 2020-12 schema;
• canonicalization and domain-separated hashing profile;
• first schema-valid ACCEPT example;
• local validation quickstart.

Validation completed before publication: the schema is valid and the example produced zero schema errors. Existing Rust CI is currently running on head f3cd5bad20330e7cf03fe20cf08c64a6f89e9998.

Next planned slice after review: fixture corpus + threat-to-fixture mapping (#184, #189).