# Stack B Capability-Placement Discovery

Version: `0.1.0-STACK-B-PLACEMENT`
Status: `BOUNDED CANDIDATE EVIDENCE / STACK-B PLACEMENT WITHDRAWN`
Authority effect: `NONE`
Runtime effect: `NONE`

## Maintainer scope correction — 2026-08-23

This package does **not** sufficiently describe what Stack B would actually do.
It is retained only as evidence about a bounded nine-carrier predication
experiment. Its earlier `EXISTING_SURFACE` recommendation is withdrawn as a
placement decision for Stack B, and no human placement answer is pending.

The Stack B M2M must be functionally rewritten and explicitly reopened before
this evidence can be reconsidered. The package may inform that conversation;
it may not define the stack by substitution.

## Result

The evidence supports nine regime-indexed carriers, `B,C,D,E,F,G,H,I,K`.
It does not establish a source law requiring one natural-language sentence per
carrier. Exactly nine controlled predication records are nevertheless a lawful
engineering projection when, and only when, an admitted structural state
contains all nine carriers and every predication traces to the source map.

The experiment's former recommendation was `EXISTING_SURFACE`: define a thin APPLICATIO-local
capability which composes existing providers. Do not create a numbered Stack B.
The capability would use OPERA T for slot-bound predication, the root
`INTERPRETATIO_CONTEXTUALIS` operation for qualified views, and Llulliana
source/admission/mediation surfaces. The published natural-language compiler
contract is consumed as an external IR interface and is not copied here.

That recommendation is no longer an active Stack B disposition. No domain
APPLICATIO may be created or registered from this package. It remains a
non-executing bounded research candidate.

## Demonstrated boundary

```text
NINE SOURCE CARRIERS
    != NINE SOURCE-MANDATED SENTENCES

COMPLETE ADMITTED B..K STATE
    -> NINE CONTROLLED CARRIER RECORDS

MISSING | AMBIGUOUS | CONTRADICTORY | UNSUPPORTED STATE
    -> SUSPEND OR REJECT; NEVER PAD TO NINE
```

The probe is deterministic and non-runtime. It proves that traceable nine-row
projection is possible without invented predicates; it does not prove that the
projection is intrinsic to the Ars Brevis or authorize its operational use.

## Governing method

This feature reduces state spaces for stochastic processes in a controlled,
reproducible, and traceable way. Reduction must preserve live alternatives,
admissions, rejections, unresolved evidence, and declared loss. The categorical
ontology of number and quality remains local to STACK ARITHMETICA.

## Package map

- `SOURCE_EVIDENCE_REGISTER.md` — exact source and claim register;
- `CAPABILITY_CONTRACT.md` — input, output, failure, and non-collapse rules;
- `PLACEMENT_DECISION_MATRIX.md` — five placement outcomes;
- `MINIMUM_PROVIDER_RESOLUTION.md` — asymmetric five-role closure;
- `EVALUATION_CORPUS.md` and `fixtures/` — positive and adverse cases;
- `schemas/` — input and output contracts;
- `data/ars-brevis-b.carrier-map.json` — source-aligned map;
- `tools/Invoke-CarrierAlignedPredication.ps1` — deterministic proof probe;
- `ROUND_TRIP_AND_LOSS_REPORT.md` — measured preservation and loss;
- `TESTS_STACK_B_CAPABILITY_PLACEMENT.md` and
  `VALIDATE_STACK_B_CAPABILITY_PLACEMENT.ps1` — validation surface.

## Exclusions

No numbered stack, root-law edit, SYSTEM_INDEX registration, Sigma, MACHINA,
deployment, canonization, runtime, or natural-language ontology is created.