The Admiralty Code grades every intelligence report on two axes meant to be independent — source reliability (A–F) and information credibility (1–6)

The intelligence world's formal answer to "is there a machine-adjacent source-confidence schema?" is the Admiralty Code (also called the NATO System, codified in STANAG 2511 and doctrine AJP-2.1). Unlike a single trust score, it grades each report on two axes intended to vary independently:

• Source reliability — a standing property of the source — rated A (completely reliable) through F (reliability cannot be judged);
• Information credibility — a property of the specific report — rated 1 (confirmed by other sources) through 6 (truth cannot be judged).

The analyst assigns the pair as a two-character rating such as "B2." Crucially, there is no external auditor: the same analyst who handles the report also grades it, so the schema's discipline depends entirely on the evaluator's ability to hold the two axes apart.

This is the intelligence-tradecraft analogue to the vault's own single source_tier field, and it belongs to the same cluster as the vault's other structured-analysis notes — Heuer's Analysis of Competing Hypotheses and its disconfirmation step. The design's stated independence is exactly the assumption that breaks down in practice, and the same two-axis split is independently re-derived by 2025 retrieval-augmented-generation research.