Dev Kit

---
name: dev_kit
description: Read the fork's declared development hooks, execution seat, readiness state, evidence locations, and supported recovery surfaces. Planner-only on demand; Developer and Reviewer receive the same inventory in boot.
category: substrate
common: false
---

# dev_kit — read the fork development contract

The fork owns `.subfloor/dev-kit.json`. Subfloor validates the declaration,
selects the invoking checkout and host/container seat, runs exact hook argv,
and retains readiness evidence under `.sc-state/local/dev-kit/`. The engine
does not infer project policy from manifests or install privileged host tools.

## Hook inventory

The supported hook names are `deps`, `test`, `lint`, and `typecheck`:

```bash
sc deps [args...]
sc test [args...]
sc lint [args...]
sc typecheck [args...]
```

Read the declaration and its executable before running a hook. A configured
hook reports the selected checkout, cwd, seat, executable, and child status.
An absent hook is `unavailable`; do not reconstruct one from package metadata.

## Canonical states

| State | Meaning | Supported recovery |
|---|---|---|
| `absent` | No declaration exists; engine-baseline tools remain mechanisms, not project policy. | Add a tracked declaration only when the fork needs one. |
| `declared` | The declaration is valid; hook configuration is known, but execution/receipt evidence decides readiness. | Run the exact configured hook. |
| `invalid` | Declaration, path, mount, image, or invocation validation failed. | Correct the named tracked input and retry. |
| `ready` | The hook can execute on the active seat or the exact Docker receipt is current. | Continue. |
| `failed` | A declared hook or provisioning attempt ran and failed. | Inspect retained logs/evidence; retry the same supported surface. |
| `stale` | Docker provisioning or package evidence no longer matches the declaration, checkout, image, or labels. | From the host, run `sc launch`; use repair only after a failed attempt. |
| `advisory` | Engine baseline is runnable while a declared native-package candidate is degraded. | Inspect the named advisory evidence and submit a reviewed tracked remediation. |
| `repair` | A retained-container repair session is open without readiness. | Exit to the host, rerun `sc launch`, and require `ready`. |

Unavailable executable = exit 126; missing hook = exit 78; invalid
configuration = exit 64. A started child preserves its own status.

## Seats and evidence

Host hooks use the host checkout and toolchain. Container hooks use the
bind-mounted checkout, engine-baseline tools, declared sandbox extension, and
current provisioning receipt. `$SC_DEV_PORT` is loopback-bound on the host and
published from `0.0.0.0` in the container. A configured `$DATABASE_URL` reaches
the fork application sidecar; it never points at the engine memory DB.

Full hook output is available with `SC_DEVKIT_OUTPUT=full`; retained
provisioning/readiness evidence lives under `.sc-state/local/dev-kit/`. Planner
uses this skill for pinch-hit development and capability design. It describes
the available surface and boundaries, not the fork's test assertions,
deployment ritual, database technique, or VM lifecycle.