# Stage 124: Wald SPRT & RRF Gate (aq124_run_wald_sprt_and_cusum_gate / DB-UNIT-10)

Cuts A/B evaluation compute 60-80% via Wald Sequential Probability Ratio stopping, detects silent distribution drift via Page CUSUM, and fuses rankers via RRF (k=60).

- Atomic micro-queue: `aq124_run_wald_sprt_and_cusum_gate` (visibility: `public_commons`)
- Backing database unit: `DB-UNIT-10` (`Signed Agent Event Feeds, Advisories & Migration Streams Core`)
- Database cell: `entities-db.teleon.dev` (`teleon_core.agent_event_feeds`, `teleon_core.signed_deprecation_advisories`, `teleon_core.verified_codemod_migrations`)
- Claim row hydration: `single_self_contained_flat_task_row` (100% context inline, normalized writeback)
- Track 2 Sister queue (`SISTER-10`): `sq10-improve-feeds-queue.teleon.dev` (Filter advisory alert noise, tune urgency weights, and pre-verify deterministic codemod patches.)
- Lanes: Wald Log-Likelihood Stop, Page CUSUM Drift Alarm, RRF k=60 Hybrid Rank

## Execution engines & AI Agent freedom contract

- **Deterministic (0 model calls)**: `signed_cloudevent_blast_matcher_v1` (Wald SPRT boundary stepper, Page CUSUM detector & RRF rank fuser (0 calls))
- **Hybrid (<=1 model call)**: `deprecation_migration_summarizer_v1`
- **AI Agent & Bot Fleet (1..6 calls)**: `autonomous_codemod_patch_synthesizer_v1` (Drift root-cause investigator & holdout refresh author)
  - Contract: **Instructions + Resources + Freedom to search for new resources and new ways not bound by instructions**

## Database invariants

- Breaking deprecation advisories join against pinned SWHID dependency edges before spawning repair tasks.
- Every migration codemod must pass deterministic sandbox verification before broadcast.

## External & internal bot fleet actions

- Terminate clearly superior or inferior challenger runs in 5-8 samples instead of fixed N=50
- Trigger automatic re-calibration tasks the moment Page CUSUM crosses h_alarm
- Fuse lexical BM25, LSH SimHash, and continuous ontology rankers without score-scale distortion

## Sister self-tuning areas

- Tune alert deduplication and breaking-change urgency weights (DIM-01, DIM-06)
- Synthesize deterministic AST codemod code_blocks for common API migrations (DIM-03)
- Tune edge delta sync intervals for high-priority security bulletins (DIM-07)