---
docType: review
layer: project
reviewType: slice
slice: pipeline-core-models-and-action-protocol
project: squadron
verdict: PASS
sourceDocument: project-documents/user/slices/142-slice.pipeline-core-models-and-action-protocol.md
aiModel: moonshotai/kimi-k2.5
status: complete
dateCreated: 20260330
dateUpdated: 20260330
---

# Review: slice — slice 142

**Verdict:** PASS
**Model:** moonshotai/kimi-k2.5

## Findings

### [PASS] Clean architectural alignment with foundational patterns

The slice design correctly implements the core abstractions defined in architecture 140:
- **Action Protocol**: Matches the specification with `action_type` property, `execute()` method, and `validate()` method returning `list[ValidationError]`
- **StepType Protocol**: Correctly defines `expand()` method returning action sequences as `list[tuple[str, dict[str, object]]]`
- **Model Resolver**: Implements the 5-level cascade chain (CLI override → action → step → pipeline → config default) exactly as specified in the architecture section "Model Resolution"
- **Registry Pattern**: Follows the stated pattern "same pattern as the agent provider registry" with module-level dicts and runtime-checkable protocols

### [PASS] Correct scope boundaries for foundational slice

The slice appropriately limits itself to "load-bearing frame" scaffolding:
- Declares `verdict` and `findings` fields in `ActionResult` for forward compatibility with slice 143 (Structured Review Findings) without implementing extraction logic
- Acknowledges `pool:` prefix by raising `ModelPoolNotImplemented`, correctly deferring to initiative 160 per architecture scope boundaries
- Uses dataclasses (not Pydantic) for internal DTOs, reserving Pydantic for slice 148's YAML loading boundary
- Creates stub modules for actions (144-147) and step types (147) without implementing them

### [PASS] Proper dependency direction and layering

- `ActionContext` maintains clean boundaries by typing `cf_client` as `object` to avoid circular imports with the integrations layer, allowing actions to cast to `ContextForgeClient` internally
- `findings: list[object]` avoids importing structured finding types from the review module (slice 143), maintaining loose coupling while providing the container for future data
- Resolver delegates to existing `resolve_model_alias()` from `squadron.models.aliases` rather than reimplementing alias resolution

### [PASS] Package structure matches architecture

The directory layout `src/squadron/pipeline/` with `actions/` and `steps/` subdirectories matches the "Package Structure" section of the architecture exactly, including the location of protocols, registries, and future action implementations.

### [PASS] Implementation respects initiative 140/160 boundary

The slice correctly implements the 140 foundation while acknowledging 160 extensions:
- Raises `ModelPoolNotImplemented` for `pool:` prefixes (architecture: "designed for, not built")
- Implements basic loop constructs but acknowledges convergence strategies are 160 scope
- Pre-declares extension points (structured findings, pools) without implementing the intelligence-layer logic
