docs/API.md is the authoritative interface reference: exports, Arbiter
methods, check options/result shape with contract invariants, all ten
relation configuration formats, valueManager, partial graphs (raw spec
+ pre-built context, precedence contract), snapshots (format, frozen
restore, trust boundary), reachability (null-defer contract), OWAFusion,
audit hook, errors, reason codes, and the validity taxonomy.
README gains a capabilities section (what the engine does and does not
do) and links the reference, per the map-vs-manual split.
The reference pass surfaced one interface gap: PartialGraphContext —
a first-class public type used in the pre-built overlay form — was not
exported. It is now part of the public surface.
Verified claims against source (overlay spec keys: challenges/
challengeProofs not proofs; qualitative routing via qualitative: true /
scaleName; simpleBinary shape; reason enum; config formats). Rigor
251/251, full suite 853/791/0.