# HANDOFF -- Blind-Spot Mapper (Evaluator E5)

**Phase:** 6 (skill-creator-max)
**Component:** Blind-Spot Mapper (E5)
**Date:** 2026-04-20
**Upstream:** Phase 4 instruction logic + Phase 5 library architecture + Phase 3B E-S05 empirical grounding
**Downstream:** Phase 7 orchestration; Phase 8 packaging; Phase 9 calibration harness; Phase 10 adversarial

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## 1. Files authored this phase

Private (under `evaluator/skills/blind-spot-mapper/`):

- `SKILL.md` -- full operating logic with references embedded into the six-phase procedure skeleton.
- `references/PRE_REGISTRATION_HALT_GATE.md` -- LOAD-BEARING halt doctrine with COMPAS / Chouldechova and Local Law 144 grounding.
- `references/FIVE_SIGNAL_INVENTORY.md` -- fixed-order integrity inventory; Signal 3 is the unique halt signal.
- `references/TAXONOMY_VERSIONING_RULES.md` -- SemVer rules for patch / minor / major bumps; major bumps are design-time reopens.
- `references/SEEDED_BLIND_SPOT_HARNESS.md` -- Phase 9 integration surface; blinded vs visible mode; catch/precision disaggregation contract.
- `references/probes/MONOCULTURE_PROBE.md` -- three-axis concentration (source / school / method).
- `references/probes/COVERT_TIER_BIAS_PROBE.md` -- frame-aligned tier inflation detection.
- `references/probes/FORCED_CLOSURE_PROBE.md` -- disagreement compression and confidence overshoot detection.
- `references/probes/PUB_BIAS_MISS_PROBE.md` -- null absence, significance clustering, replication-contested citation.
- `references/probes/RETRACTION_MISS_PROBE.md` -- Retraction Watch / Crossref / publisher query; load-bearing severity roll-up.
- `references/probes/AI_CONTAMINATION_MISS_PROBE.md` -- registry-anchored domain / intermediate / laundering detection.
- `templates/PROBE_FINDING_RECORD.md` -- per-probe, per-signal, and run-summary record schemas.

Public Evaluator contribution (under `evaluator/_public/`):

- `_public/bias-taxonomy/BLIND_SPOT_TAXONOMY.md` -- versioned taxonomy store; six representative entries (one per probe) at v1.0.0.

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## 2. Pre-registration enforcement confirmation

The pre-registered fairness / audit criterion is load-bearing and is enforced at three layers:

1. **Procedural (Phase A of SKILL.md):** no probe may execute until the criterion is registered, hashed, and written to the Evaluator Search Ledger. Phase B, C, D, E, F are gated on successful Phase A.

2. **Signal (FIVE_SIGNAL_INVENTORY.md, Signal 3):** Signal 3 is the ONLY signal that halts the run. Absent, ambiguous, or mid-run-modified criteria trigger CRITICAL finding to Audit Charter Lock (E6) and halt.

3. **Hash (PRE_REGISTRATION_HALT_GATE.md, immutability enforcement):** criterion hash is computed over (fairness definition, threshold, claim-type scope); any subsequent write to the criterion during the run is detected by hash mismatch; mismatch invalidates the run, emits CRITICAL to E7, and excludes the run from E9 statistics.

Three-layer enforcement closes the post-hoc selection failure documented by Chouldechova and the definition-dependent under-report pattern documented in the NY State Comptroller's 17x delta.

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## 3. Zero-overlap verification

- All probe retrieval goes through Frame Host (E3) retrieval hooks. No probe reads RAM's search ledger.
- All writes go to the Evaluator Search Ledger (owner E4). None to RAM's search ledger.
- The blind-spot taxonomy store is under `evaluator/_public/` and is inaccessible to RAM skills per Phase 5 library architecture.
- The AI-contamination probe explicitly forbids using RAM's own AI-detection output.
- The retraction probe explicitly uses Evaluator retrieval hooks, not RAM's.

No RAM surface appears in any E5 file.

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## 4. Flags and open dependencies

- **OPEN (Phase 4 consequence):** the "most fragile assumption" from SKILL.md -- pre-registration feasibility across all claim types. If exploratory qualitative synthesis is admitted at Phase 3 / 4, E5 design reopens.
- **OPEN (Phase 9):** seeded-case catalog per probe and per signal; embedding-similarity calibration for the AI-contamination probe; 3x-delta calibration for Signal 1.
- **OPEN (Frame Host dependency):** retrieval hooks for Retraction Watch, Crossref, AI-content registry must be wired in Phase 7 orchestration; E5 assumes they exist but does not own them.
- **OPEN (E9 co-emission channel):** the diagnostic metadata co-emission channel must be created in Phase 5 / 7 cross-cutting artifacts; the schema is defined in PROBE_FINDING_RECORD.md.
- **FLAG (taxonomy):** initial taxonomy v1.0.0 ships with representative entries only; first production runs will accrete genuine entries. E9 staleness detection should NOT fire on the early-run taxonomy before at least one Phase 9 calibration cycle has populated entries.
- **FLAG (probe version tracking):** AI-contamination probe has shortest heuristic lifespan; Phase 4 must schedule a periodic probe-version review (quarterly recommended).

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## 5. Traceability

- Facet Map: E5 Blind-spot mapping.
- Solution Architecture: Section 4.E5 (probe library + taxonomy + seeded hooks); Section 9.1.
- Source Registry: E-R5.1 (PASS, empirical grounding thick; cascade from E-S02 does NOT trigger).
- Library Architecture: Section 4.5 (E5 private and public placements); Section 5.2 (build order); Section 6 (taxonomy versioning reference).
- Phase 4 SKILL.md: operating logic preserved; Phase 6 expansion is additive (probe references externalized; seeded-harness surface added; public taxonomy seeded).

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## 6. Next steps

- Phase 7 (orchestration-engineering-max): wire Frame Host retrieval hooks; wire E9 co-emission channel; sequence E6 -> E5 intake; define E5 -> E7 findings pipe; define E5 -> E9 diagnostic metadata pipe.
- Phase 8 (plugin-packaging-max): include `_public/bias-taxonomy/` as Evaluator-public; preserve `references/probes/` subdirectory.
- Phase 9 (calibration harness): produce seeded-case envelopes per probe; calibrate 3x-delta threshold against absolute-count context; calibrate AI-contamination embedding-similarity threshold.
- Phase 10 (adversarial): stress the pre-registration gate with post-hoc-selection attempts; stress the taxonomy with genuinely novel patterns; stress probe-narrowing resistance under simulated throughput pressure.

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**End of HANDOFF.**
