# Phase 173 Summary: LibRPA QSGW Bounded Target And Trust Contract

**Status:** Done
**Date:** 2026-04-14
**Axis:** Axis 1 (layer capability) + Axis 2 (inter-layer connection)

## What was done

Phase `173` closed the target-selection and trust-contract slice for milestone
`v1.99`.

### Chosen positive lane

- fresh topic mode: `first_principles`
- fresh topic slug: `librpa-qsgw-deterministic-reduction-consistency-core`
- chosen target candidate:
  `candidate:librpa-qsgw-deterministic-reduction-consistency-core`
- chosen target type: `claim_card`

### Honest narrowing decision

The phase explicitly did **not** treat `LibRPA QSGW` as already fully
converged. Instead it chose the already evidence-backed
**deterministic-reduction thread-consistency core** on the bounded
`H2O/really_tight iter=10` reference case.

### Contract surfaces produced

- fresh `first_principles` topic shell
- local-note source anchors for:
  - the LibRPA codebase root
  - the workflow/validator trust note
  - the existing OMP inconsistency engineering report
  - the existing deterministic-reduction consistency report
- `librpa_qsgw_target_contract.json|md`
- candidate ledger row for later promotion
- baseline summary, atomic concept map, operation manifest, trust audit, and
  strategy-memory artifacts for the bounded route

## Acceptance criteria

- [x] One fresh `first_principles` topic is bootstrapped for the bounded `LibRPA QSGW` lane
- [x] One bounded positive `LibRPA QSGW` target is chosen with explicit codebase and workflow anchors
- [x] One benchmark, validator, or trust contract makes that target honest enough for later promotion
- [x] Explicit non-claims prevent the target from drifting into unsupported full-convergence or whole-stack closure
- [x] One isolated acceptance lane proves the target-contract surface mechanically

## Evidence

| Artifact | Location | Purpose |
|----------|----------|---------|
| `pytest-librpa-qsgw-target-contract.txt` | `phases/173-librpa-qsgw-bounded-target-and-trust-contract/evidence/` | Isolated runtime-script receipt for the bounded LibRPA QSGW target-contract lane |
| `pytest-first-principles-routing.txt` | `phases/173-librpa-qsgw-bounded-target-and-trust-contract/evidence/` | Supporting proof that first-principles routing semantics still hold |
| `librpa-qsgw-target-contract-acceptance.json` | `phases/173-librpa-qsgw-bounded-target-and-trust-contract/evidence/` | Raw replay payload with target contract, candidate ledger, source anchors, and trust artifacts |
| `receipt.md` | `phases/173-librpa-qsgw-bounded-target-and-trust-contract/evidence/` | Human-readable replay receipt |

## What this phase proved

1. The remaining user-requested `LibRPA QSGW` lane now has one honest bounded
   positive target instead of a vague “ingest the whole codebase” ambition.
2. The target is anchored to real code files, real validator surfaces, and real
   engineering evidence rather than prose alone.
3. Phase `173.1` can now focus on authoritative-L2 promotion of one bounded
   QSGW unit instead of re-litigating what the positive target even is.
