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P221 — AIEP — Reasoning Trace Schema

Status: Open Source Prior Art Disclosure Licence: Apache-2.0 Published by: Phatfella Limited Priority: Defensive prior art disclosure based on work conducted prior to GB2519711.2 filed 20 November 2025 Architecture Layer: AIEP Phase 2 Support Layer

Overview

This document defines the open Reasoning Trace Schema (RTS) for the Architected Instruction and Evidence Protocol (AIEP) architecture. The schema is published as defensive prior art under the Apache 2.0 licence to establish public domain availability of this specification and prevent future patent capture by third parties.

The RTS defines a canonical format for recording the complete trace of a reasoning session: the evidence artefacts consulted, the inference steps taken, the causal rules applied, and the output claims produced. Implementations may use this schema to produce inter-operable traces consumable by audit tools, governance systems, and external verifiers.

Field

Reasoning trace standards for evidence-bound AI systems. Applicable to any system implementing the AIEP evidence ledger model or conformant derivative.

Schema Motivation

A standardised trace format enables: cross-vendor interoperability of reasoning audit tools; deterministic replay of reasoning sessions by any conformant implementation; governance policy evaluation against standardised reasoning records; and research and benchmarking of reasoning quality.

ASCII Architecture

Reasoning Session
     |
     v
+----------------------------------------------+
| Reasoning Trace Producer (any AIEP impl.)    |
+----------------------------------------------+
                    |
                    v  (RTS-formatted trace)
+----------------------------------------------+
| Reasoning Trace Schema (RTS)                 |
|                                              |
|  session_id                                 |
|  evidence_artefacts_consulted[]             |
|  inference_steps[]                          |
|  causal_rules_applied[]                     |
|  output_claims[]                            |
|  quality_scores{}                           |
+----------------------------------------------+
                    |
                    v
   Any conformant trace consumer
   (audit tools, governance, verifiers)

Canonical Schema Definition

{
  "schema_version": "1.0",
  "session_id": "<sha256-of-session-context>",
  "started_at": "<ISO 8601>",
  "completed_at": "<ISO 8601>",
  "world_state_snapshot_hash": "<sha256>",
  "evidence_artefacts_consulted": [
    {
      "artefact_hash": "<sha256>",
      "consulted_at_step": "<integer>",
      "relevance_score": "<float 0.0-1.0>"
    }
  ],
  "inference_steps": [
    {
      "step_id": "<integer>",
      "step_type": "evidence_retrieval | causal_inference | simulation | arbitration",
      "input_hashes": ["<sha256>"],
      "output_hash": "<sha256>",
      "rule_applied": "<rule_id or null>",
      "compute_tokens": "<integer>"
    }
  ],
  "causal_rules_applied": [
    {
      "rule_id": "<string>",
      "rule_version": "<semver>",
      "applied_at_steps": ["<integer>"]
    }
  ],
  "output_claims": [
    {
      "claim_id": "<sha256>",
      "claim_type": "factual | causal | predictive | normative",
      "claim_content": "<structured claim>",
      "evidence_support_hashes": ["<sha256>"],
      "confidence": "<float 0.0-1.0>"
    }
  ],
  "quality_scores": {
    "evidence_support": "<float>",
    "internal_consistency": "<float>",
    "causal_coherence": "<float>",
    "novelty_risk": "<float>",
    "composite": "<float>"
  },
  "trace_hash": "<sha256 of entire record>"
}

Prior Art Statement

Publication of this schema as open-source prior art establishes public domain availability as of the publication date. No patent claim may restrict implementation of this schema in its published form.

Licence

Dependencies

P01R
P203
P204