Hooks Reference

The complete hook/event catalog — the gregCore equivalent of Oxide’s hook index. Source of truth: game_hooks.json (1,850 methods, 22 groups) + framework/greg_hooks.json (canonical registry, manifest v2) + generated docs/FrameworkAPI.md. Usage patterns: Developer Events Hooks Guide; concepts: Core Events.

How to read a hook

Each game_hooks.json row: { Group, Namespace, ClassName, MethodName, ReturnType, IsVoid, Parameters[] }. Full ID form: greg.{Group}.{ClassName}.{MethodName}. Lua per-group sugar: greg.hooks.<lowercase_group>.on_<snake_case_method>(cb) + greg.hooks.<group>.list() + greg.hooks.groups().

The 22 groups (counts)

Group	Hooks	Typical content
VisualUI	605	Screens, panels, HUD widgets, update loops
Networking	180	Cables, routes, switches, patch panels, maps
World	163	Time, scene, environment, placement
Economy	137	Money, XP, reputation, shop, checkout
Persistence	121	Save/load, serialization, waypoints
Lifecycle	120	Boot, scenes, mods, game state transitions
Character	112	Player controller, movement, interaction
Hardware	95	Servers, racks, devices, IDs, screens
Input	74	Keys, actions, keypads, locks
Uncategorized	73	Awaiting curation — prefer grouped equivalents
Settings	34	Options, config, difficulty
Interaction	24	Clicks, pickups, usable objects
Audio	20	Mixers, volumes, effects
UnityEngine	20	Engine callbacks
Serialization	17	DTOs, bytes, snapshots
Facility	12	Walls, rooms, furniture
Maintenance	9	Repair, technicians, jobs
CustomImport	8	ModLoader item/prefab injection
Tutorials	8	Onboarding flows
Steam	7	Lobbies, achievements (observe-only)
DevTools	6	Consoles, REPL, diagnostics
Ignored	5	Explicitly excluded from dispatch

Curated hook names (stable, prefer these)

ID	Emitted from	Payload highlights
greg.PLAYER.CoinChanged	Player.UpdateCoin	data["Amount"]
greg.PLAYER.XpChanged / ReputationChanged	player patches	new totals
greg.RACK.*	RackPatch (position used/freed)	rack hash, position
greg.SYSTEM.ButtonCheckOut	ShopPatch.OnCheckOut	cart snapshot
greg.lifecycle.scene-loaded	MelonMod.OnSceneWasLoaded	scene name
greg.lifecycle.update	MelonMod.OnUpdate	dt
SystemGameLoaded / SystemGameSaved, GameLoaded / GameSaved	gregNativeEventHooks	save identity
Money / Xp / ReputationChanged, Day / MonthEnded	native event hooks	totals / time

Numeric IDs 1001–4001 (EventIds, GetByEventId) exist for compat — prefer string IDs in new code.

Lua domain API (the other half of “hooks”)

Events tell you when; these tell you what now (all guarded — safe defaults outside the game):

• greg.player — position() → {x,y,z}, money() / set_money(v) / add_money(n), xp() / set_xp(v), reputation() / set_reputation(v), teleport(x,y,z), is_crouching() / is_sitting()
• greg.server — get_all() → [{id, hash, is_on, is_broken, size_u?, x, y, z}], get_list(), count(), broken_count(), find_by_id(id) / find_by_ip(ip), repair(id), repair_all() → number, power_on/off(id), set_ip(id, ip), set_customer(id, customerId)
• greg.switch — get_all(), get_list(), count(), broken_count(), find_by_id(id), repair(id), repair_all()
• greg.tech — free_count(), total_count(), dispatch_server() → 1/0, dispatch_switch() → 1/0
• greg.rack — get_all(), count(), is_position_available(rackId, position), get_used_count(rackId), mark_used / mark_free(rackId, position)
• greg.cable — get_all(), count(), get_next_id()
• greg.patch — get_all() → [{id, hash, x, y, z}], get_list(), count(), find_by_id(id), has_cable(id)
• greg.customer — bases() → [{base_id, customer_id, money_speed, all_met, wants_internet, satisfied}], is_ip_present(baseId, ip), app_id_for_ip(baseId, ip) → number (-1 unknown), register_subnet / unregister_subnet
• greg.economy (read-only) — sheet() → {total_salary, months}, history() → [{month, day, salary, repair, shop}]
• greg.shop — items() → [{idx (1-based), name, price, xp, type, id, unlocked}], unlock(idx), buy(idx), cart() → [{ref, name, price, qty, total}], cart_add/ref, cart_remove(ref)
• greg.net (read-only saves) — routers() → [{asn, next_route_id, routes, owned}], firewalls() → [{cluster_ip, rules}], sfps() → [{prefab, x, y, z, inserted}], lacps(), cables() → [{id, maxspeed}]
• greg.mods — list() → [{id, name, version}], is_loaded(idOrName), version(idOrName), declare({{mod, min_version, required}}), ensure({mod, min_version?, required?}) → ok, detail, check() → problems (empty = ok)
• greg.requests (read-only) — list() → [{number, state, short, long, rewarded, done, progress}], current_number()
• greg.subnet — mask_from_cidr(cidr) (pure math), usable_ips(subnet) (game needed, capped 65,536), first_usable(subnet)
• greg.items — register_shop_item(subfolder, spec), register_static_item(subfolder, spec); spec keys name, price, xp, size_u, mass, scale, model, texture, icon, type (snake_case or PascalCase)
• greg.world — time_of_day(), day(), seconds_in_day() / set_seconds_in_day(v), time_scale() / set_time_scale(v), pause() / resume() / is_paused(), scene(), difficulty(), save(), server_count() / rack_count() / switch_count(), open_all_walls()
• greg.ui — notify(msg, seconds?), log / log_info / log_warning / log_error(msg), register_mod_config_tab(tab_id, label, fn)
• greg.computer — register_shortcut(id, label, fn_or_appid), unregister_shortcut(id), register_app(appId, title, on_open_fn[, on_close_fn]), unregister_app(appId), open_app(appId), close_app(), current_app(), list_shortcuts(), list_apps() (see Guidebook Computer UI)
• Tablets/widgets — tablet_open(title) / widget_open(title, x, y) (x, y required) → id ("" = failed), panel_add_label / panel_add_section / panel_add_spacer / panel_add_button(id, label, fn) / panel_add_toggle / panel_add_slider, panel_toggle(id) → visibility, panel_visible(id), panel_close(id)

Regenerating this catalog: scripts/Generate-GregHooksFromIl2CppDump.ps1 → game_hooks.json; scripts/generate_api_docs.py → docs/FrameworkAPI.md; scripts/validate_contracts.py checks coverage claims (two denominators: raw dump vs curated registry — see docs/modding/api/coverage.md).