version: "1.0.0" name: combat-mechanics description: Battle-mechanics data and predicates in views/utils/combat/ — OASW (anti-sub first strike), AACI (anti-air cut-in), AAPB (anti-air propellant barrage) and special attacks. Use when editing anything under views/utils/combat/ or views/utils/{aaci,oasw,aapb,sp_attack}.ts, when adding or validating ship/equipment eligibility conditions, when asked to "check game data" / "new ships were added" / "update combat conditions", or when a battle prediction looks wrong for a specific ship.

Combat Mechanics (views/utils/combat/)

Package layout

All battle-mechanics logic lives in views/utils/combat/:

• types.ts — GameShip = APIShip & APIMstShip, GameEquip = APISlotItem & APIMstSlotitem

(merged objects, state spread over master data: { ...$ship, ...ship }), plus ShipPredicate / EquipPredicate / EquipsPredicate.

• combinators.ts — generic builders: shipIdIs, equipIdIs, ctypeIs, itemTypeIs

(api_type[2]), iconIs (api_type[3]), validAll / validAny / validNot, hasSome, hasAtLeast, slotNumAtLeast, taisenAbove.

• ship-predicates.ts / equip-predicates.ts — shared named predicates.

predicates.ts is a barrel over all three.

• aaci/ — table / entries / api split (types and predicates hoisted to package root).
• aapb.ts, oasw.ts, sp-attack.ts — each imports from the shared pool; feature-specific

predicates stay local.

Note that combinators.ts's validAll / validAny / validNot operate on a single GameEquip[]. oasw.ts works with two-arity (ship, equips) predicates and therefore defines its own local overSome / overEvery (lodash's cannot type mixed arity) plus overEquips to lift an equips-only predicate. Do not substitute one family for the other — see references/oasw.md.

Merged-object convention: all four modules take merged GameShip / GameEquip. Consumers do the merge in their selectors (see the oasw-indicator.tsx pattern). This is safe because state and master-data field names do not collide except api_id, which no predicate uses (state wins).

Back-compat shims — do not delete: views/utils/{aaci,oasw,aapb,sp_attack}.ts remain as deprecated re-exports/adapters because external poi plugins import those paths (same reason isOASWWith exists). The aapb / sp_attack shims adapt the old [state, mst] pair-based signatures.

Intentionally not shared: isFletcherClassOrKai differs between AACI (id list, includes Heywood) and OASW (ctype 91 + isKai, future-proof) — kept separate on purpose. Likewise isBattleship (AACI: stype 8/9/10) vs sp-attack's isBattleShip (adds stype 12).

isKai is ship.api_getmes === '<br>'. api_getmes is an APIMstShip field whose value is '<br>' for every remodeled (Kai and above) form; base ships carry the acquisition message.

The single most important lesson

Prefer `ctypeIs` over ship-id lists whenever the wiki's eligibility column names a class (級 / -class). A ctype predicate absorbs new class members for free.

Real bug this caused: AACI types 38–41 matched the Atlanta class by ship id [597, 696], so Reno (991) and Reno Kai (747) — same ctype 99 — never triggered. Fixed by isAtlantaClass = ctypeIs(99). Other id-list predicates are still worth re-auditing against their wiki wording.

Reference tables

Validated condition tables live alongside this skill — read the relevant one before editing:

• references/oasw.md — OASW activation conditions per ship/class, plus

the equipment-type predicate reference.

• references/aaci.md — AACI validation state, the resolver tie-break,

shared group predicates, key ship/equipment ids.

• references/sp-attack.md — every special-attack id, its predicates,

and the valid ship combos.

These replace the former views/utils/combat/{aaci,oasw}.md. Keep them here rather than beside the modules, so there is one place to update.

Sourcing and validation

• Primary source: wikiwiki.jp/kancolle (per-mechanic pages; links live in the file comments).
• WebFetch summaries of the wikiwiki anti-air cut-in table are unreliable — row numbering

drifted by ±1 across calls. Always cross-check a claimed type number against the individual ship's own wiki page. Asking the fetch prompt to _quote the eligibility column verbatim_ (rather than infer from row order) works well.

• Good cross-check when a wiki summary is doubtful — KC3Kai upstream source:

https://raw.githubusercontent.com/KC3Kai/KC3Kai/develop/src/library/modules/AntiAir.js

• en.kancollewiki.net returns 403 and kancolle.fandom.com returns 402 to WebFetch — do not

retry those.

Game-data sweep method (reusable)

When asked to check for new game data:

1. New ships / equipment — diff local master data: newest api_start2/getData/*.json

capture, fields api_mst_ship (player ships are api_id < 1500) and api_mst_slotitem. See the redux-api-testing skill for where captures live. Captures only go back ~10 days, so this catches recent patches only; for anything older, check the predicate against the wiki directly.

1. Quests — see the quest-goal-data skill.
2. Most new ships get no unique combat mechanics — only marquee/anniversary ships do.

Check assets/data/quest_goal/ first (grep for the nation name, for escortshipclass / flagship: name arrays, and for # extend when ... comments) before assuming OASW / AACI / sp-attack need touching. The 2026-07 French additions (Algérie 641, Vautour 643, Béarn 645) needed _only_ quest 373's name arrays.

1. Run npm run typecheck and npm test -- --testPathPattern="combat" after editing.

Standing decisions — do not re-raise

• AACI type 53's 1.6 modifier is provisional. wikiwiki still marks that cell ?. The user

asked to leave it until the wiki updates; do not raise it on every sweep.

• Ships 743 (Naganami Kai Ni Ho) and 744 (Asashimo Kai Ni Ho) are not part of the 32nd

Division group used by AACI 49–52; 1034 / 745 (Suzunami Kai Ni / Kai Ni Ho) are.