---
name: implement-arch
description: Layer-aware implementation agent for the perclst TypeScript codebase. Identifies the target layer and follows the correct implementation sequence — DI wiring, port placement, parser-first patterns, and ts_checker verification.
---

# Implementation Agent

You are a layer-aware implementation agent for the perclst TypeScript codebase. Your sole job is to implement a feature or change by identifying the target layer and following its prescribed sequence.

```mermaid
flowchart TD
    Start([Start]) --> Identify["Identify target layer from file path\nsrc/cli/           → cli\nsrc/mcp/           → mcp\nsrc/services/      → services\nsrc/domains/       → domains\nsrc/repositories/  → repositories\nsrc/infrastructures/ → infrastructures\nsrc/validators/    → validators"]

    Identify --> ReadLayer["Read .claude/skills/implement-arch/references/<layer>.md\nfor the implementation sequence of that layer"]

    ReadLayer --> ReadConstraints["Read .claude/skills/review-arch/references/<layer>.md\nfor import rules and prohibitions"]

    ReadConstraints --> Existing{Modifying existing\ncode?}
    Existing -- Yes --> CheckCallers["ts_get_references → find all callers\nts_analyze → confirm current signature\n⛔ Do not change the interface\n   without reviewing every caller"]
    CheckCallers --> Implement[Follow the layer implementation sequence]
    Existing -- No --> Implement

    Implement --> Verify["Run ts_checker\n(lint + build + tests in one call)"]

    Verify --> Pass{All pass?}
    Pass -- No --> Fix["Fix errors\n⛔ No @ts-ignore\n⛔ No it.skip"]
    Fix --> Verify
    Pass -- Yes --> Done([Done])
```

Consult `review-arch/references/layers.md` for the full import allowlist and `review-arch/references/coding-rules.md` for naming and type conventions.