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name: add-part description: Scaffold a new Starblaster Part (a slotted ship upgrade with Mk.1–9 scaling). Use when adding a new upgrade that mutates player stats. Implements the extend-Part / slot_type / apply+unapply / PartFactory pattern, checks balance, and verifies. Follows docs/contributing/04 and chains the part-author / economy-sim agents.

/add-part — guided Part scaffold

Full reference: docs/contributing/04-player-parts-economy.md. Parts are how the player gets ANY stats — the ship starts at zero and Parts populate it.

Procedure

1. Gather intent

Confirm: which player stat(s) the Part affects, its slot_type (see scripts/weapons/SlotTypes.gd for the slot enum), the Mk.1–9 scaling curve (how the effect grows per mark), and roughly its cost tier. For balance judgment (is the per-Mk delta worth the price?), consult the economy-sim / game-design agents.

2. Implement via the part-author agent

The part-author agent owns this pattern:

• Extend Part.
• Set slot_type in _init.
• apply(ship) — additive: add to the ship's stat AND record the delta.
• unapply(ship) — reverse exactly that recorded delta (so swapping/removing the Part cleanly undoes it — this is why the delta is recorded, not recomputed).
• Mk scaling via the mark multiplier.
• Register the Part in PartFactory (else it can't be offered/equipped).

3. Verify + ship

Run the /ship skill: parse_check + headless boot (confirm the Part script compiles and the ship can equip it) + commit .uids + push + report to the user.

4. Balance pass (if it shifts the curve)

If the Part changes the power/cost curve meaningfully, run the economy-sim agent to sanity-check run economics before considering it final. Mention the relevant design docs (docs/archive/economy_2026-05-24.md, docs/archive/weapon_mk_progression_2026-05-25.md) for context.

Notes

• For a pure data .tres Part instance with no new code, the data-author agent is the lighter path; new behavior needs part-author (code).
• Cross-refs: docs/contributing/04, the "New Part" convention in CLAUDE.md.