Add a claim warrant, and stop it from moving the root gate

[Silentpartnercoding]

resolvable_reference() decides whether a parentless claim names anything checkable, and UnattributedRootError is a hard gate on it. It checks shape, not existence — so it stops "trust me" but admits a well-formed DOI that was never registered.

The warrant is the next rung: which kind of check applies, whether it needs an oracle, and what happened when it ran.

The distinction

measured · cited → deterministic, mechanically re-checkable
inferred · analogized → oracle_conditional, needs a judge

verify_outcome is three-valued on purpose — unverifiable must never collapse into rejected. A dead URI costs an adversary nothing and produces no failed check.

Where it goes

The evidence object, which was already required and already unconstrained. No node field changes, no migration, nothing requires a warrant, and untyped evidence resolves exactly as before.

Why graph.py is touched at all

A warrant's source_digest is a hex string matching the accepted hash form. Flattened into evidence it would satisfy resolvable_reference and admit a root that was previously refused — a hard gate moving as a side effect of attaching metadata.

A warrant describes how a claim could be checked. It is not evidence that the claim named anything. So placement is normative, under a reserved key, and resolvable_reference skips that key by name.

Nested dicts are already skipped by the isinstance guard, so the skip is explicit rather than load-bearing today — it keeps the guarantee if that function ever learns to recurse.

Verification

tests/test_claim_warrant_gate.py — 4 tests, including one that demonstrates the failure being prevented: prose alone returns None, prose with a flattened warrant returns "hash".

25 tests green across test_provenance, test_benchmark and the new suite. Untyped inputs verified unchanged: {}→None, "trust me"→None, DOI→doi, URL→url, hash→hash, arxiv→arxiv.

Vocabulary borrowed, nothing imported

The four-way typology is the classical set of pramāṇas. The modern formulation is cited by DOI (Kadaboina 2026, Apache-2.0). The schema is written locally with local field names — no external package is a dependency, and nothing here validates that work's formal claims. If that repo vanished, nothing here breaks.

Not included

The mapping table — ledger_adapter.py is not in this repository, so one side of it does not exist. docs/ records two corrections found in review, including a coverage rule: untyped is a first-class stratum, and a screen that reports a clean result over a minority of classified nodes reproduces the exact failure it exists to catch.

🤖 Generated with Claude Code