Complete Phase 2: make benchmark output drive per-rule improvement, wire the
loop-owned ledger, and turn a confirmed false positive into a score knob. Zero
new dependencies; detection stays byte-identical (recall 44/47 = 93.6%, FP 0%)
and the 90/10 gate holds.
- Per-rule attribution (4.1): BenchmarkMiss/BenchmarkFalsePositive carry rule_id;
BenchmarkMetrics.per_rule aggregates matched/missed/false_positives per rule.
- Recommendation delta (4.2): evaluate_benchmark emits RuleRecommendation
(keep/shadow/loosen) written to rule_policy_delta.json; the inert
next_improvement_candidate stub is now rule-aware ("rule:<id>" or
"language_hunter").
- Loop ledger (4.3): cli loads the ruleset with the rule_policy.json overlay
(empty -> byte-identical; an entry overlays a rule's status/floors at load);
read_rule_ledger/write_rule_ledger added for the evolve loop. A disabled rule
in the ledger no longer fires (covered by an integration test).
- FP -> reachability knob (4.4): a confirmed false-positive learning lowers a
finding's effective reachability multiplier in the score
(fp_reachability_overrides + scoring reachability_override) instead of deleting
the rule, so recall stays high while the score stops over-penalizing.
93 tests pass; ruff + mypy clean. Spec tasks 4.1-4.4 checked off — Phase 2
(Core: rules-as-data + benchmark signals) is complete. The loop-driven decision
to apply ledger flips remains the gated evolve loop (Phase 3/4).
Co-Authored-By: Claude Opus 4.8 <[email protected]>
Externalize detection rules to versioned TOML and remove rule-local severity, so
rules detect and the central CWE policy decides severity — fixing "rules too
influential / not centrally managed". Zero-dependency; detection is byte-identical
(benchmark recall 44/47 = 93.6%, FP 0% unchanged) and the 90/10 gate holds.
- RulesetStore (ruleset/store.py + ruleset/<lang>/rules.toml): PatternRule as data
(rule_id, title, languages, cwe, tags, pattern, status, min_evidence_level,
precision_estimate, version) with NO severity; load_ruleset (sorted, with
optional rule_policy.json ledger overlay) and a stdlib TOML write_ruleset. The
32 rules were generated from the prior PATTERN_RULES with a verified exact
round-trip (pattern/cwe/languages/tags/title).
- findings.py: drop the hardcoded PatternRule class + PATTERN_RULES tuple; load the
default ruleset from TOML; quick_scan_findings(root, targets, rankings, ruleset,
policy) resolves each finding's severity from policy via resolve_severity
(SEVERITY_LABEL maps 0-5 -> string) and tags findings with their rule status.
- Three-status volume control: StaticFinding gains status (default "enabled");
disabled rules never fire; shadow findings are partitioned out of the report and
score in the CLI (written to shadow_findings.json) — no shadow rules by default.
- Emission floors (RulesetConfig.min_emit_priority / min_emit_precision, default
0.0 = emit all) replace "every match is a finding".
- CLI loads the ruleset as a stage and uses it for the fail-loud policy check,
detection, hunter pool, and the score CWE map. Wheel ships the ruleset TOML.
85 tests pass; ruff + mypy clean. Spec tasks 3.1-3.4 checked off.
Co-Authored-By: Claude Opus 4.8 <[email protected]>
