docs/runicnpc/PLAN.md

RunicNPC — the plan

Status: plan, written 2026-09-30. Its eight questions (§11) were answered the same day: D221–D228 (§0). Stage 0 closed 2026-09-30 (runicnpc-rust#1/#2, §9): v0.1.0 released and loaded on both rigs. D229–D230 were decided with it. Stage 1 measured 2026-09-30 (§9): six answers on both rigs; D231 was decided with it. Stage 2's design answered 2026-09-30: D232–D238 (§0), which reshape stage 2 (§9). Stage 2 built and tested 2026-09-30 on both rigs (§9); its API is API.md. Stage 3's design answered 2026-09-30: D239–D242 (§0).

RunicNPC is Runic Gateway's own NPC plugin for Rust servers, in its own repository, RunicGateway/runicnpc-rust. It runs on Oxide and Carbon. Other plugins drive it through an API, as NpcSpawn is used, and admins use it directly in game through chat commands. It is a prerequisite of the rest of the Rust plan: the redesigns resume only after its stage 9 (§9), and from then on module-rust requires it, as it requires Kits.

It replaces PLAN_REDESIGNS.md §6's "two routes". That section's spike was run on 2026-09-30, and the org lead chose neither route (D214). What the spike found is §1 here, because every choice below rests on it.

Its decisions continue the Rust workstream's numbering at D214 (PLAN_REDESIGNS.md §10). The repository carries the same conditions as every Runic Gateway repository: GPL-3.0-or-later, Conventional Commits, AI-assisted work disclosed, branches cut from an up-to-date base, and the org lead's approval before any architectural or design decision is implemented.

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0. The direction, in the org lead's words (2026-09-30)

#	Decision	Rejected
D214	Runic Gateway writes its own NPC plugin, an API-style plugin like NpcSpawn, in its own repository. It may borrow behaviours the other plugins implement, never their code.	Extending rust.npc.place on Rust's scientists alone (route A); HumanNPC (route B); depending on NpcSpawn.
D215	It is not only for events. Admins place NPCs in game, where they want them, for normal play, so it has chat commands.	NPCs only as event steps.
D216	No visual editor. Profiles are authored on the website; in game there are commands only.	NpcSpawn's in-game GUI (and the 22 images it needs).
D217	Kits is how an NPC is equipped, and Kits is required. A profile names kits; it has no item lists of its own.	Wear and belt lists in the profile.
D218	Loot tables are RunicNPC's own for now. Links to other loot plugins can come later.	AlphaLoot, CustomLoot, Loottable or LootManager as a dependency.
D219	Rust's own navmesh is used. A custom navigation mesh is a later stage, built only if a real need appears (§8, stage 10).	Shipping NpcSpawn-style point meshes from the start.
D220	The plugin is built and tested in stages before the Rust plan resumes, and it then becomes a plugin module-rust requires.	Building it alongside the remaining redesigns.
D221	RunicNPC works without Runic Gateway too (Q1). Standalone, its profiles live in its data file and console commands edit them. On a Runic Gateway server, the site's profiles replace that file on every push, and in-game profile edits are refused with "this server's profiles are managed by its website".	Runic Gateway only.
D222	Placements live on the server (Q2). They keep respawning while the site is offline; the site catches up when it returns, and lists and edits them from then on.	The site as the only record.
D223	Our NPC is its own subclass of Rust's scientist, with its own brain (Q3). The brain is kept small and tested on Rust's staging branch before each forced wipe.	Rust's scientist plus patches.
D224	The installer and the egg ship it from the bundle, pinned and checksummed (Q6). It is also published as a release on Gitea, and possibly on other sites for anyone to download.	Operators installing it themselves.
D225	Per-profile kills are public and usable in titles (Q4), like the NPC kills column today.	Admins only.
D226	edge → main, like the other Rust repositories (Q5, D18).	PRs straight to main.
D227	No default caps. Instead, a realistic warning of what a number of NPCs costs and its impact on the server, measured in stage 1, shown wherever NPCs are added (Q7). Caps exist only when an admin sets them.	100 / 50 / 10 per second by default.
D228	RunicNPC.cs, console name RunicNPC, chat command /rnpc, permissions runicnpc.* (Q8).	—
D229	The empty repository was seeded by one chore: commit straight to main (the licence and a stub README), edge was branched from it, and everything after goes by PR (stage 0). It is the only direct push.	You seeding it in the Gitea UI; the whole scaffold straight to main, unreviewed.
D230	The layout is plugin/RunicNPC.cs and a root plugin.toml: api, the framework floors, requires_plugins (stage 0). RunicNPC is one file, not an overlay of a server tree.	Mirroring Rust-Plugins' overlay/oxide/plugins/ and overlay.toml.
D231	Each profile (or group) decides whether its NPCs target other NPCs, and which kinds: Rust's scientists, animals, other profiles, and so on (stage 1; the org lead's words). Rust's AI cannot do this (§9, stage 1, Q3), so it is our own combat state and sensing, and stage 5 opens with a spike for it.	Our NPCs fighting players only, as Rust's scientists do.
D232	The swap copies a fixed list of fields, generated from Rust's unmodified assembly by a tools/ script and carried in the plugin, so Oxide and Carbon copy the same fields. A boot check on Carbon, where Rust's visibility is unmodified, names any field Rust has added since; the staging drill (stage 9) regenerates the list.	Stage 1's rule as it is (Oxide copies runtime state too); the rule with Oxide-only filters.
D233	A roamer moves in one of three ways: wander (our own: a walkable point within a radius of its spot, walk, pause, repeat), monument (Rust's own AI-zone paths), or route:<name> (points an admin records in game, walked in order). The profile sets the default, wander, and each placement may override it (the org lead: "should be both, and the ability for admins in game to make routes").	Our wander only; Rust's paths in monuments and ours elsewhere, fixed; the mode fixed per profile.
D234	Routes are walked from stage 2 and recorded from stage 3. Stage 2 builds the follower and the routes file (the harness writes its points); stage 3 adds /rnpc path record and setting points in game; stage 5 adds fighting and resuming the route.	Recording in stage 3 and walking in stage 5, as first planned.
D235	An NPC sleeps when no player is within 160 m (Rust's own dormant distance; a profile may change it, 0 = never). It walks back to its spot before it sleeps (the org lead: "it should walk back home before going to sleep"), and wakes when a player comes within range.	Being put back at its spot; never sleeping unless a profile opts in.
D236	Respawn is chosen per placement: each (the default: every NPC returns its delay after its own death) or group (none return until all are dead, then all return together).	One fixed rule.
D237	A deleted profile leaves its placements waiting. Their NPCs despawn; the placements are kept and shown as "profile missing" in game and on the site; they spawn again if the profile returns.	Refusing the delete; deleting the placements with it.
D238	A profile's shape is §2's, as the org lead approved it: names, kits, prefab, role, movement, health, damageDealt, damageTaken, aimCone, ranges, visionCone, sleepDistance, healthThresholds, in data/RunicNPC/profiles.json with the managed flag. Placements and routes have their own files beside it; the optional caps (D227) are in the plugin's config. Stages 5–7 add their own sections.	A smaller stage-2 profile, combat values deferred to stage 5.
D239	A roamer may be placed wherever Rust's navmesh reaches, a player-built floor included, and the answer warns when it is one ("this spot is on a player-built structure; if it is destroyed, the NPC falls back to the nearest navmesh"). Sentry-only stays the rule for a spot that is truly off the mesh. Stage 10 shrinks to pasted or custom prefabs and moving platforms (stage 2's finding).	Allowing it silently; keeping anything player-built sentry-only even where the mesh covers it.
D240	A route is recorded point by point: /rnpc path record <name> starts it, /rnpc path point adds where the admin stands (checked against the navmesh; a bad point is refused with the reason), /rnpc path undo drops the last, /rnpc path save [loop|back] writes it, /rnpc path cancel discards it. Nothing is drawn on screen (D216).	The same flow with the points drawn on screen; a point dropped every few metres as the admin walks.
D241	A placement made in game is named after its profile and a number (/rnpc place bandit answers "Placed bandit-3"), and /rnpc rename <id> <new> renames it. /rnpc near lists the names.	Bare numbers; the admin naming every placement.
D242	/rnpc place and /rnpc here take key=value options in any order after the profile: count=, respawn=, mode=each|group, move=wander|monument|route:<name>, radius=. Anything left out takes the profile's default.	/rnpc place bandit 3 300 group route:gate; /rnpc place then /rnpc set.

Borrowing, not copying. NpcSpawn states no licence at all, so its source grants us nothing and is read only as a description of what can be done in Rust. HumanNPC is MIT on uMod, which is GPL-compatible, but §1.2 rules out its design, so there is nothing of it worth carrying. RunicNPC's code is written from how Rust's own classes behave (the HOOKS and OXIDE_API mirrors, and rig probes), and every borrowed idea is credited in §3 by what it is, not by copied text.

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1. What the spike found (2026-09-30, the Oxide rig)

The probe was a throwaway plugin, RgNpcSpike.cs. It spawned NPCs by each route, watched them for minutes, made them fight, killed them, and read what the bridge published through the sidecar's /events. The org lead stopped the Carbon half: one server was enough to see that HumanNPC does not behave as needed.

1.1 Rust's own scientist, stripped and given a kit (route A)

Question	Answer
Does the kit stick?	Yes. Strip(), Kits' GiveKit, then EquipWeapon(): after three minutes of combat it still wore the kit. Rust does not re-dress it.
Does it fight with the kit's weapon?	Yes. Every hit it landed was pistol_revolver.entity, from a revolver kit. Its prefab loadout was an LR-300.
Can it be named?	No. ScientistNPC overrides displayName with a get-only property that answers "Scientist". Setting _displayName stores the name and changes nothing.
Is it counted correctly?	Yes. IsNpc is true, so every bridge path treats it as an NPC.
Cost	Under Oxide's slow-call warning; no measurable hitch.

1.2 HumanNPC 0.6.8 (route B) — ruled out

• Its NPCs are counted as players. It spawns player.prefab with a made-up user id and Harmony-patches BasePlayer.IsBot for every player on the server. IsNpc stays false, and that is what the bridge tests. The sidecar recorded a player.death for "Hobb" (steamId 11419803648) and a player.tally crediting "Hobb2" with an NPC kill: a fake player in the public killfeed, the leaderboard and the titles.
• The API the old plan named does not exist. There is no SpawnHumanNPC or SetHumanNPCInfo: only CreateNPCHook(position, rotation, name, clone, saved). Kit, hostility and invulnerability can be set only by reflection into its private types. Its RefreshNPC and RemoveNPC are public without [HookMethod], so Oxide's Call cannot reach them either.
• Its combat is simulated. Its hits carried no weapon and a flat ~7 "Bullet" damage, even with a bow.
• Its persistence leaks. saved: false holds only until anything else saves: one saved NPC wrote every unsaved one to its data file. A dead NPC came back on the next reload. RemoveNPC never marks the file dirty, so removed NPCs return at the next restart.
• It is slow. ~250 ms to create, ~250 ms to apply settings, ~250–320 ms to remove, each on the main thread.
• It breaks on Rust updates. Nearly every release since 2023 is "fix for Rust update"; 0.6.0 fixed servers that failed to load.

1.3 NpcSpawn 3.4.8 (the org lead's suggestion)

It worked, and it is the model RunicNPC borrows from:

• It replaces the scientist's component with its own subclass, CustomScientistNpc : ScientistNPC, copying the serialised fields across (EntityManager.CopySerializableFields). No Harmony. IsNpc is true, so the bridge counts it correctly unchanged.
• The name sticks, and it is written into the victim's death screen (AttackerInfo).
• Kits work, and it fought with the kit's revolver (with NpcAttackMode: 1; its default only attacks a whitelist).
• It is never saved (enableSaving = false). After a hard kill and restart, none of three came back. Reloading NpcSpawn kills all of its NPCs.
• Spawning took 4–106 ms.

Its costs, which RunicNPC avoids by design: a 2.1–2.8 s main-thread hitch at every boot (it scans ten million candidate ids and generates spawn points); a version check over plain HTTP to a bare IP on every boot; it unloads itself if any of its 22 GUI images is missing; it is not on uMod and states no licence, so it cannot be bundled; and it has had 78 releases.

1.4 Two corrections to the old plan

• "displayName already flows into the killfeed" is wrong for every route. The bridge names an NPC attacker by initiator.ShortPrefabName (RunicGateway.cs, DescribeAttacker), so the feed says scientistnpc_roam. Stage 4 fixes it.
• HumanNPC's API, as described, does not exist (§1.2).

1.5 A rig trap found on the way

A data directory created by the panel's file API is not writable by the game (IOException: Permission denied from Directory.CreateDirectory). Let a plugin create its own data directory, then write files into it. The installer and the egg must do the same with any data RunicNPC ships.

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2. What RunicNPC is

One plugin file, RunicNPC.cs, compiled by Oxide or Carbon from source, like the bridge. It declares // Requires: Kits, so neither framework loads it without Kits (D217).

Its NPC is its own type, a subclass of Rust's ScientistNPC with its own brain. This follows NpcSpawn's approach (§1.3), because only a subclass can:

• override displayName;
• override the aim cone;
• write its name into the victim's death screen;
• carry behaviours Rust's brain does not have (guard, escort, boss phases).

Stage 1 proves the swap on both frameworks before anything is built on it.

It owns nothing it is not asked for. Every NPC has an owner, and the owner decides its lifetime:

Owner	Who	Survives a restart?
run:<runId>	An event run, through the bridge	No. Never saved; the bridge's registry reverts it, as world.place does today.
placement:<id>	An admin's placement in game, or one made from the site	Yes, as a placement: RunicNPC stores the spot, profile and respawn delay, and spawns a fresh NPC there at boot. The NPC itself is never saved.
plugin:<name>	Any other plugin using the API	No. It is killed when that plugin unloads.

This split is what HumanNPC got wrong: the placement is persistent data, the NPC never is. There is exactly one save path, a flag marks it dirty on every change (including removal), and nothing else is written.

Standalone or managed (D221). Without a site, RunicNPC reads its profiles from its own data file and console commands edit them. With a site, the bridge pushes the site's profiles, which replace the file; the file records that it is managed, and in-game profile edits are refused with "this server's profiles are managed by its website". Placements stay the server's either way (D222): the site reads them and edits them through the bridge.

A profile is a named description of an NPC:

• Appearance: name (or a list to pick from), the kits it wears, body type, and the prefab it starts from.
• Combat: health, damage scales (overall, and by head, body, legs and melee), aim spread, and ranges (sense, chase, roam, attack).
• Behaviour: its role and AI states (§6).
• Loot: its loot table (§7).

The kit list is required and non-empty; one kit is picked at random per spawn, for variety within a profile. A kit the server does not have refuses the profile when it is saved, not when an NPC spawns.

In the data file (D238), data/RunicNPC/profiles.json:

{
  "managed": false,
  "profiles": {
    "warden": {
      "names": ["Warden", "Old Warden"],
      "kits": ["warden_rifle", "warden_smg"],
      "prefab": "scientistnpc_roam",
      "role": "roamer",
      "movement": { "mode": "wander", "radius": 20 },
      "health": 250,
      "damageDealt": 1.0,
      "damageTaken": { "head": 1.0, "body": 1.0, "legs": 1.0 },
      "aimCone": 2.0,
      "ranges": { "sense": 30, "loseTarget": 40, "chase": 40, "attack": 30 },
      "visionCone": -0.8,
      "sleepDistance": 160,
      "healthThresholds": [0.5]
    }
  }
}

• role is roamer or sentry in stage 2; the other roles of §6 arrive with their stages.
• movement.mode is wander, monument or route:<name> (D233). A placement may override it.
• damageDealt scales the kit weapon's damage. damageTaken scales what the NPC takes, by body part.
• sleepDistance 0 means it never sleeps (D235).
• healthThresholds are the fractions at which OnRunicNpcHealth fires (§4).

A deleted profile leaves its placements waiting (D237): their NPCs despawn, and they spawn again if it returns.

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3. Features

Borrowed ideas are marked with their source; everything else is new. Stage numbers are §9's.

3.1 From NpcSpawn (behaviour only)

Feature	Stage
A scientist subclass with its own brain; never saved	2
Names, a random name from a list; body type and skin tone chosen by the NPC's id	2
Health, overall and per-body-part damage scales, aim cone, headshot rule	2
Sense, listen, chase, roam and attack ranges; a vision cone; hostile-only; ignore safe-zone, sleeping or wounded players	2, 5
Sleep when no player is within a distance, and walk home	2
States: roam, chase, combat, idle, stationary combat	2, 5
NPC-versus-NPC and NPC-versus-animal rules, with allow and deny lists	5
Group alert: nearby allies join a fight	5
Turrets may target them, and they fight back	5
Healing with syringes; grenades, smoke, rockets, flamethrowers, melee (by the weapon the kit gives)	5
Parenting to a moving entity	10
Loot tables, a crate on death, removing the corpse	7
TruePVE / NextGenPVE compatibility (CanEntityTakeDamage)	5

3.2 From HumanNPC (behaviour only)

Feature	Stage
Press E to talk: an NPC says a line, or opens a message, when used	6
Lines on greet, hurt and kill	6
Walk a recorded path (D234), and follow a player	2, 3, 5

3.3 Runic Gateway's own

Feature	Stage
Profiles authored on the website and pushed to each server, per server, shared, or fleet-wide (the zone-presets pattern, D210). The site checks every kit exists before it saves.	4
Admin placement in game by chat command (§5), persistent, with respawn delays; the site lists and edits the placements	3, 4
Correct accounting: an NPC is never counted as a player; its name reaches the killfeed, event log and death screen; kills are counted per profile	2, 4
Per-profile stats and titles: "Warden kills", boss kills; the killing blow and every player who did damage	4
Cost warnings, not default caps (D227): what N NPCs cost the server, measured in stage 1, shown when an admin places them, on the site's profile and placement pages, and in doctor. Caps (per server, owner or profile, and a spawn rate) exist only when an admin sets them	2, 4
Event ownership: run-owned NPCs with the bridge's restart and teardown guarantees	4
Waves and phases without a core change: a phase advances on "n NPCs of profile X died", and on "the boss fell below 50%"	4, 6
Zone tethering: an NPC held inside a ZoneManager zone (from redesign §3)	5
Guard and escort: hold a point or an entity; follow a convoy or a player	5
Factions: profiles hostile or allied to each other; allied to a team or clan, for defend-your-base events	5
Bosses: an on-screen health bar, phases at health thresholds, announcements (popup, chat, Discord and the app through engagement), a reward on the kill	6
Quest-giver or vendor: passive, press E for a site-written message	6
The live map and the app: markers for event NPCs and bosses, "guards left: 3/8"	8
Operator-friendly: shipped in the bundle, no phone-home, no image files, no boot scan; doctor reports it; RunicNPC's permissions appear in the site's permission manager like any plugin's	2, 4
An API for other plugins, versioned, documented, and usable without Runic Gateway at all (D221)	2, 9

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4. The API

Other plugins call RunicNPC by name through Call, which on Oxide reaches non-public methods and public ones marked [HookMethod] (§1.2 is what happens otherwise). Every name is prefixed, so no hook of another plugin is ever matched by accident. The first draft, fixed in stage 2 and published as docs/runicnpc/API.md:

Call	Does
RunicNpc_ApiVersion() → int	The API's version. The bridge refuses a RunicNPC older than it needs, and says so in hello.
RunicNpc_Spawn(Vector3 at, string profile, string owner, JObject overrides) → BasePlayer	Spawns one NPC, or returns null and logs why. overrides may change any profile value for this NPC only.
RunicNpc_Despawn(ulong netId) / RunicNpc_DespawnOwner(string owner) → int	Removes one, or all of an owner's.
RunicNpc_List(string owner) → List<Dictionary<string, object>>	The owner's live NPCs: id, profile, name, position, health.
RunicNpc_Profiles() / RunicNpc_SetProfiles(JObject all)	Reads, or replaces, the profile set. Replacing marks the server as managed by a site (D221).
RunicNpc_Placements() / RunicNpc_SetPlacement(...) / RunicNpc_RemovePlacement(string id)	The persistent placements (§2).
RunicNpc_IsRunicNpc(BaseEntity e) → bool, RunicNpc_ProfileOf(BaseEntity e) → string	Lets another plugin tell our NPCs apart.

Hooks it raises (void; a returning hook can cancel a death, see PROTOCOL.md §8.7): OnRunicNpcSpawned(npc, profile, owner), OnRunicNpcDied(npc, profile, owner, HitInfo, contributors), OnRunicNpcHealth(npc, profile, fraction) (at the thresholds a profile names), OnRunicNpcDespawned(npc, owner), OnRunicNpcUsed(npc, player).

The bridge is its only link to the site. RunicNPC never talks to the sidecar. The bridge calls the API and listens to the hooks, which keeps "the sidecar is a dumb forwarder" true.

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5. In game: the chat commands (D215, D216)

/rnpc (and the same verbs in the server console as rnpc.<verb>), each behind a RunicNPC permission. Those permissions reach the site's permission manager through the inventory, like any plugin's.

Command	Does	Permission
/rnpc place <profile> [key=value ...]	Places at the spot you are looking at, persistent, and answers with its name (D241). Options in any order (D242): count=, respawn= (seconds), mode=each|group, move=wander|monument|route:<name>, radius=	runicnpc.place
/rnpc here <profile> [key=value ...]	The same, where you stand	runicnpc.place
/rnpc remove [placement]	Removes a placement and its NPCs: the one named, or that of the NPC you are looking at	runicnpc.place
/rnpc rename <placement> <new>	Renames a placement (D241)	runicnpc.place
/rnpc near [radius]	Lists placements (by name) and live NPCs near you	runicnpc.place
/rnpc path record <name> · point · undo · save [loop|back] · cancel	Records a route where you walk, point by point (D240)	runicnpc.place
/rnpc path list · delete <name>	Lists or deletes routes; a placement on a deleted route waits, as for a deleted profile (D237)	runicnpc.place
/rnpc info	The NPC you are looking at: profile, owner, health, target, state	runicnpc.place
/rnpc profiles	The profiles this server has	runicnpc.place
rnpc.profile <create|set|delete> ... (console)	Edits a profile on a standalone server; refused when the site manages them (D221)	runicnpc.admin
/rnpc tp <placement>	Teleports you to a placement	runicnpc.admin
/rnpc respawn [placement|all]	Respawns a placement's NPC now	runicnpc.admin
/rnpc clear <owner>	Removes every NPC of an owner (e.g. a stuck run)	runicnpc.admin

Every placement is checked against Rust's navmesh (D219). Every placement also answers with the cost warning (D227): how many RunicNPC NPCs the server now has and what stage 1 measured that number to cost.

On the navmesh, the NPC roams, chases and fights normally, and that includes a player-built floor, which Rust's mesh covers a moment after it is built (stage 2). On a player-built structure the placement is made with a warning (D239): if the structure is destroyed, the NPC falls back to the nearest navmesh. Off the mesh (a pasted structure, a custom prefab), a stationary profile is placed and a roaming one is refused with the reason. An event step gets the same answer, as a blocked RaidableBases spot does (D208).

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6. Behaviour

Each profile has a role, which sets its AI states and defaults:

Role	Behaviour
Roamer	Moves in one of three ways (D233): wander within a radius of its spot, monument (Rust's AI-zone paths), or route:<name>; chases and fights. The profile sets the default, a placement may override it.
Sentry	Stationary: turns and shoots, never walks. The only role allowed off the navmesh.
Guard	Holds a point or an entity; chases only to its leash, then returns.
Patrol	A roamer on route:<name> (D233): walks a route recorded in game (/rnpc path record); fights and resumes (stage 5).
Escort	Follows an entity or player; defends it.
Boss	Any of the above, plus a health bar, phases and announcements (§3.3).
Passive	Never fights; press E to talk. Quest-givers and vendors.

Factions are a relation table between profiles, plus optional ties to a team or clan: hostile, neutral or allied. Rust's scientists are one more faction, so a profile can be told to leave them alone.

Zone tethering keeps an NPC inside a ZoneManager zone. At the edge it turns back, and if it ends up outside (it was pushed, or the zone moved) it is returned home. ZoneManager is already required by module-rust; to RunicNPC it is optional, and a profile that asks for a tether on a server without it is refused at save.

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7. Loot (D218)

A profile's loot table: items with chances and amounts, optionally clearing the corpse's default loot, dropping a crate, or removing the corpse. Tables are authored on the site with the profile. Adapters to AlphaLoot and the others are a later stage and not planned in detail here.

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8. Navigation (D219)

Rust's navmesh is the only one in stages 1–9. Every spike NPC walked and fought on it, and NpcSpawn itself shipped no custom mesh. Where it does not reach, a profile is a sentry (§5).

Stage 10, only if needed: a point graph recorded in game. An admin walks the route, /rnpc mesh record <name> samples it, and NPCs move between the points directly, as NpcSpawn's custom meshes do, for:

• pasted structures, and roofs the mesh does not reach (a player-built floor needs none: Rust's mesh covers it a moment after it is built, stage 2 and D239);
• custom map prefabs Rust's mesh does not cover;
• moving platforms, together with parenting.

Stage 10 starts only when a real event or placement needs one, and its own spike decides the file format and cost.

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9. The stages

Each stage is built, then tested on the Oxide rig, then on the Carbon rig, then PR'd with its docs. A stage that touches the site also has a browser walk, signed in as an admin, on every new page. A stage whose acceptance needs a player in game writes that walk down, and it is done before the stage closes.

Stage 0 — The repository

• LICENSE.md (GPL-3.0-or-later), CODE_OF_CONDUCT.md, CONTRIBUTING.md (with the AI-disclosure rule), SECURITY.md, README.md, PR template.
• Branches main and edge (D226).
• CI on every PR: a static reader like Rust-Plugins' checkPlugin.js: every hook it declares is known, none returns a value where one would cancel a game action, and the API version in the source equals the manifest's.
• Release on main: runicnpc-<ver>.tar.gz holding runicnpc/RunicNPC.cs and a manifest.json (version, API version, sha256), plus SHA256SUMS, using the same release engine as Rust-Plugins.
• tools/, never shipped: the rig harness (stage 1) and the panel scripts (rig.js, con.js), reading tokens at call time.
• Workspace and org updates: the CLAUDE.md repository table and the org landing page (.profile), because the project's shape changes.

Done when an empty plugin releases through CI and loads on both rigs.

As built (2026-09-30, runicnpc-rust#1):

• The plugin has // Requires: Kits and [Info("RunicNPC", "Runic Gateway", "0.0.0")], whose version the release replaces. It answers RunicNpc_ApiVersion() (API 1) and rnpc.status (version, API version, which hooks have fired). It spawns nothing.

• plugin.toml (D230) declares api = 1, requires_plugins = ["Kits"] and the floors it was loaded on: Oxide 2.0.7726 and Carbon 2.0.259. The Oxide floor is newer than the bridge's 2.0.7585, because the rig runs 7726 and RunicNPC has never run on anything older.

• scripts/checkPlugin.js runs the bridge's checks (every hook listed in ExpectedHooks and void unless listed in ANSWERS_DELIBERATELY; chat-command signatures). It adds three of its own:

  • no RunicNpc_* call may be public without [HookMethod], because Call cannot reach it (the trap in §1.2);
  • // Requires: must equal requires_plugins, and Kits must be in it;
  • there must be exactly one [Info] line, because the release stamps that line.

  It has 23 self-tests, including the real plugin and a CRLF checkout: on Windows, an attribute pattern that only knew \n stopped seeing [HookMethod].

• The release reuses Rust-Plugins' release engine unchanged. Its packaging step ships runicnpc-<ver>.tar.gz, holding runicnpc/RunicNPC.cs and manifest.json, whose fields are component, version, commit, repo, api, the floors, requires_plugins and files with each file's sha256. It ships SHA256SUMS beside it. It does not ask the installer to rebuild its bundle until stage 4 makes RunicNPC part of that bundle.

• tools/: rig.js and console.js, not con.js. CON is a reserved device name on Windows, so git there cannot open a file of that name, even with an extension. The panel address and server ids moved into a git-ignored tools/rigs.json.

• Loaded from the branch on both rigs: rnpc.status answered api=1 hooks=1 fired=1 on Oxide and on Carbon (Carbon compiled it in 217 ms).

• Also updated: the workspace CLAUDE.md repository table, which now lists every org repository, and the org landing page (.profile#7).

Stage 1 — The spike

A harness plugin (tools/RunicNpcHarness.cs) answers, on both rigs, what stage 2 depends on:

1. The subclass swap (CopySerializableFields into our ScientistNPC subclass and brain) spawns, walks, fights and dies cleanly on Oxide and Carbon.
2. enableSaving = false holds across a hard kill and restart (§1.3 did this for NpcSpawn only).
3. Which ranges and scales hold on the brain without our own states, and which need them.
4. Navmesh coverage: a placement check at every monument of the 6000 map, and on a roof.
5. The cost of spawning 1, 10 and 100, and of 100 idle and 100 fighting, as the server's frame time. These numbers are the cost warning's (D227), so they are measured on both rigs and on the 6000 map.
6. The name in the death screen, and what the bridge publishes for a kill by and of our NPC.

Done when each has a measured answer written into this plan, and the org lead has picked anything the answers leave open.

Measured (2026-09-30, tools/RunicNpcHarness.cs, runicnpc-rust#3). Both rigs ran the same world for this: the Oxide rig was regenerated to the Carbon rig's 6000 map, seed 981448696, 12 GB. Costs were measured on one rig at a time, with the other stopped, because they share the node's CPU. Nobody was connected. Each answer below held on both frameworks unless it says otherwise.

How the harness makes a player. Q6 and the fighting load need a player, and the rigs have none. At the org lead's suggestion, the harness spawns stand-ins: player.prefab with a made-up user id above Rust's bot range (11400000001 and up). IsNpc is false, so Rust's AI and the bridge treat one exactly as a player. This is §1.2's HumanNPC lesson, used on purpose. A stand-in never connects, and only the harness makes one.

1. The swap works, with one step the plan did not know about.

• CreateEntity(prefab, pos, rot, startActive: false) must be followed by gameObject.AwakeFromInstantiate() before Spawn(). That is the call GameManager.CreatePrefab makes itself when active is true. Without it the entity still spawns, is networked and even thinks. But Unity never starts the brain, so it has no AI design, no navigator and no state. It stood still for 90 s.
• With that call, the swap takes 9–16 ms. The NPC is our type (RnhNpc, RnhBrain), IsNpc is true, it is not saved, it keeps its name, and it wears and holds its kit (pistol_revolver.entity).
• It walks, chases and fights a player with its kit's weapon: it killed a stand-in from 12–13 m in 14–20 s, every hit a pistol_revolver.entity. It dies cleanly. Its corpse, an NPCPlayerCorpse, carries its name.
• The field copy differs between frameworks. The rule "public and not [NonSerialized], or [SerializeField]" copied 64 NPC and 32 brain fields on Carbon, but 124 and 36 on Oxide. Oxide's patcher makes private fields public, so on Oxide the rule also carries runtime state across. It worked on both, but stage 2 needs a rule that selects the same fields on both, for example a list read from Carbon's result and checked on Oxide.

2. enableSaving = false holds. Five of ours were never saved and one was, as a control. After server.save, a hard kill and a restart, none of the five came back, on either rig, matched by net id. The control came back, but as a plain ScientistNPC named "Scientist": a saved subclass loses its type and its name when the server loads it. That is the other reason our NPC must never be saved (§2).

3. What holds on Rust's brain, and what needs our own states.

Setting	Result
Health, name, aim cone	Hold: set on the NPC and read back (400/400, the name, 0.5).
Sense range, target-lost range, vision cone, listen range, hostile-only, sense types	Only if set before the brain starts. Senses.Init copies them once. At 35 m, a range of 50 set before the start saw the target, and the same range set afterwards did not.
The prefab's own values	Sense 30 m, lose target 40 m, vision cone −0.8, listen 10 m, memory 10 s, line-of-sight checks on, hostile-only off, senses players only, health 150, aim cone 2.
Roaming	Rust's roam only follows an AI zone's move points (and so does its chase: stage 2). In a monument's zone (Desert Military Base) ours roamed 36–47 m in 60 s. In an open field it stood still (0 m). A roamer anywhere but a monument needs our own roam state, so stage 2's roamer role includes one.
Sleep	An NPC outside an AI zone is never put to sleep, and ai_dormant does not apply to this AI. So an idle NPC keeps thinking with nobody near, which is what the costs below measure.
Fighting NPCs	Rust's scientist AI never attacks an NPC. HumanNPC.IsTarget is true only for non-NPC players, pets and scarecrows. IsFriendly means "same prefab id", which the swap copies, so every stock scientist counts ours as a friend. Re-implementing Rust's internal IAISenses puts a scientist in our NPC's target list. But Rust's AI design never runs its attack event for an NPC target. Calling AttackTick directly passed line of sight every time and still fired no shot, because the design's cover and facing states win. NPC-versus-NPC combat needs our own combat state, and sensing NPCs needs our own sensing (see the cost below). D231 makes it a profile setting, so stage 5 opens with its own spike.

4. Navmesh. Rust's scientists walk Rust's own navmesh (its Gen2 RustNavMeshAgent), not Unity's: a Unity NavMesh query found nothing in the open world. The placement check is Rust.Ai.Gen2.RustNavMeshHelpers. SamplePosition, the same helper Rust's navigator uses. It answers false until RustNavigation.Instance. IsDefaultNavmeshBuilt(). On a map's first boot that took 8–10 minutes (477 s on Carbon, 604 s on Oxide); later boots load the saved proceduralmap.<size>.<seed>.<n>.navmesh. Placements that respawn at boot must wait for it.

	Carbon	Oxide
Monuments probed (9 points each)	144	144
Points on the navmesh	1,152 / 1,296 (89%)	1,151 / 1,296 (89%)
Of those on a structure (a roof or raised floor)	132 / 209 (63%)	130 / 211 (62%)
A player-built floor 4 m up	not on the mesh in the frame it spawned; on it 0.1–0.3 s later (stage 2)	the same
One check	13.6 µs	8.3 µs

Monument roofs (Launch Site, Airfield, Trainyard, the warehouses) are mostly walkable. This stage read player-built floors and roofs as never walkable; stage 2 corrected that (the row above), and D239 follows from it.

5. The cost (D227's numbers). Seven 60 s phases on a field 400 m from any monument: a baseline, 1, 10 and 100 of ours idle, the same 100 shooting 20 stand-ins (whose damage the harness zeroes, so none die), a fresh 100 set to fight NPCs beside 100 stock scientists, then empty again. Every phase also had one 1–3 s spike from the autosave, so the table quotes the median frame rather than the worst.

Phase	Oxide: median frame / fps	Oxide: time per think / each NPC thinks every	Carbon: median frame / fps	Carbon: time per think / each thinks every
Baseline, empty	16.4 ms / 52.7	—	17.3 ms / 46.6	—
1	16.7 / 50.7	0.09 ms / 0.28 s	17.3 / 48.1	0.05 ms / 0.29 s
10	16.6 / 51.8	0.04 ms / 0.28 s	17.7 / 47.4	0.03 ms / 0.29 s
100 idle	17.7 / 48.3	0.04 ms / 0.30 s	18.9 / 41.8	0.03 ms / 0.33 s
100 shooting 20 players	21.6 / 44.5	2.5 ms / 2.5 s	22.1 / 43.1	2.4 ms / 2.6 s
100 sensing NPCs, beside 100 scientists	26.4 / 33.9	17.7 ms / 7.5 s	26.1 / 33.9	20.4 ms / 8.2 s
Spawning 100 at once	a 552 ms hitch (5.5 ms each)		a 483 ms hitch (4.8 ms each)

What the numbers say:

• The two frameworks cost the same. Every row agrees within about 1 ms, so one warning serves both.
• This rig is slow. An empty server runs at about 50 fps, not its 240 target. The warning therefore reports what NPCs add, not an absolute fps.
• Idle NPCs are cheap: 100 add about 1 ms to the median frame.
• Fighting NPCs hit Rust's AI budget before they hit the frame rate. Every human NPC's thinking shares aithinkmanager.framebudgetms, 2 ms per frame. At 100 fighting, each NPC gets to think only every 2.5 s, so they react sluggishly while the median frame rises by only about 5 ms. The warning has to say both things.
• Sensing NPCs the way Rust does, with a line-of-sight test to every candidate, costs about 7× more per think than fighting players. 100 NPCs sensing each other make roughly 100² tests. D231's NPC targeting must sense differently, for example by testing only the profiles it is hostile to, nearest first.
• Spawn in batches. 100 in one frame is a half-second hitch; stage 2 spreads a large placement over frames.

6. The name on the death screen, and what the bridge publishes.

• HumanNPC.AttackerInfo writes the prefab's short name as the killer, after BasePlayer has written the display name. The death screen said "scientistnpc_roam" until our NPC overrode it. With the override it says "RnhWarden", and the weapon stays pistol_revolver.entity.

• Open for the in-game walk: the client may use that string to pick the killer's portrait. Only a real client shows whether the override costs the portrait.

• What the bridge publishes (protocol 13):

  • our NPC kills a player → player.death with attackerType: "npc", attackerName: "scientistnpc_roam" (the prefab name, as §1.4 said), the weapon and the distance;
  • a player kills our NPC → only player.tally with npcKills: 1 and the weapon. Nothing names the NPC or its profile.

  Both are stage 4's to fix: the NPC's name in the feed, and a death frame with its profile.

• Left on the rigs: each rig's sidecar store now has the stand-in "RnhDummy" (11400000001) as a player, with one death and one tally row. It is test data on test rigs; a wipe clears it.

Stage 2 — The NPC and its API

• The NPC: the subclass with a fixed field list (D232) and AwakeFromInstantiate before Spawn (stage 1, Q1); the AttackerInfo override, so its name reaches the death screen (stage 1, Q6); profiles read from RunicNPC's own data file in §2's shape (D238); a random kit and name per spawn; appearance and combat values, with the sense values set before the brain starts (stage 1, Q3).
• Roles and movement: roamer and sentry. A roamer's three modes (D233): our own wander, Rust's monument paths, and route:<name> from the routes file (D234; the harness writes its points, stage 3 records them in game).
• Sleep (D235): past the profile's distance from every player, the NPC walks back to its spot, then stops thinking; a player in range wakes it.
• Navmesh at boot: nothing spawns until RustNavigation.Instance.IsDefaultNavmeshBuilt() (stage 1, Q4); the queue waits for it.
• Owners and lifetimes (§2): placements persisted with one dirty flag, each with its count, delay and respawn mode (each or group, D236) and an optional movement override; a placement whose profile is gone waits (D237); standalone profiles and the managed flag (D221).
• Spawning in batches: large placements and the boot respawn are spread over frames, within a per-frame time budget (stage 1, Q5: 100 at once is a half-second hitch).
• Optional caps, off by default, in the plugin's config, and the cost warning from stage 1's table (D227).
• The API (§4) and its hooks; docs/runicnpc/API.md.

Tested by the harness asserting each call's result (PASS/FAIL lines read back over the panel), plus restart and reload checks on both rigs: no NPC saved, every placement back, nothing left behind by an unloaded owner. It also checks each movement mode, sleep and the walk home, both respawn modes, and a placement whose profile is deleted and restored.

Built (2026-09-30, runicnpc-rust#4, API version 2). The API as built is API.md. What else landed:

• tools/fieldlist generates the swap's field list from the Carbon rig's assemblies (tools/managed.js downloads them). It picks 64 NPC and 32 brain fields, exactly stage 1's Carbon count. On both rigs every name resolves, and Carbon's boot check finds no field Rust has added.
• tools/RunicNpcTest.cs, the harness: rnt.run api|hooks|move|sentry|sleep|place|all, then rnt.after after a reload or restart.

Group	What it proves	Oxide	Carbon
api	every call's answer; seven refusals (bad owner, placement: owner, unknown or refused profile, bad override, off the navmesh)	24/24	24/24
hooks	spawned, a health threshold once, body damage ×0.5, died with contributors (250 of 250), despawned	8/8	8/8
move	wander within its radius; a route in order (3>0>1>2>3>0); a monument roamer 36 m on Rust's roam; our chase to 9.6–9.8 m of a 10 m chase range, and giving up twice	8/8	8/8
sentry	holds 0.00 m for 40 s and hits a target 12 m off 29–34 times; stands 40 m up, off the navmesh, for 20 s	7/7	7/7
sleep	wanders 8.6 m off, walks home at ≤2.8 m/s when no player is within 160 m, sleeps 1.7 m from its spot, stays still, wakes	7/7	7/7
place	each returns only the dead one; group waits for all, then all return; a deleted profile waits and returns; a missing route waits	14/14	14/14
a plugin unloads	its NPCs are removed with it	pass	pass
RunicNPC reloads	every placement back, the world equals the registry, no plain scientists at the spots	5/5	5/5
the server restarts	the same, after server.save, a restart, and the navmesh load	5/5	5/5

What building it found:

• Outside a monument, Rust's scientists never chase. Rust's chase state looks for an AI zone's move points and returns an error without them, as its roam does (stage 1, Q3). A wander or route roamer therefore has our own chase. It closes to three quarters of the attack range, never past the profile's chase range from home, and if the target stays out of reach at that edge for 5 s it gives up and walks home. A monument roamer keeps Rust's chase.
• Rust's navmesh covers a new player-built floor in 0.1–0.3 s (2–3 frames), on both rigs. Stage 1's "a player-built floor is never on the mesh" (Q4) sampled in the same frame the floor spawned, so it is wrong: a roamer can stand on a player-built floor a moment after it exists. §5's sentry rule, §8 and stage 10 were written on stage 1's reading; the org lead answered with D239, and those sections now follow it.
• Rust's navmesh sampler reaches further down than across. A roamer asked to stand on a roof found the ground 4.7 m below. A roamer's spot must now be within 2 m, up or down, of the navmesh it is put on.
• A brain can think before Unity has started it. For that moment it has no navigator, so RunicNPC leaves that think to Rust.
• A hit with no body part reports every part at once ((HitArea)(-1): fire, explosions, falls). Only an exact head or leg hit uses those scales; everything else is body.
• The game manifest's entity list leaves out the NPC prefabs. A profile's prefab is looked up in its prefab list instead.

Stage 3 — In game

The chat and console commands (§5), their permissions, the navmesh placement check with D239's warning on a player-built structure, respawn delays, and recording routes in game point by point (D234, D240). Placements made in game are named after their profile and a number, and renamable (D241). /rnpc place and /rnpc here take key=value options, a movement override and a respawn mode among them (D233, D236, D242).

Tested by the harness for everything a console can reach (the commands' parsing, refusals, names, and the route file a recording writes), then a written in-game walk: place, remove, rename, look-at info, respawn, record a route and place a patrol on it, place on a player-built floor and destroy it, restart. This is the first stage that needs a player on a rig.

Stage 4 — Runic Gateway integration

Across four repositories, split into 4a–4c if it grows:

• Rust-Plugins (the bridge):
  • hello reports RunicNPC's presence and API version;
  • world.place for an NPC takes a profile, and the placing is RunicNPC's;
  • the killfeed names NPCs by their name (§1.4);
  • new frames: an NPC died, with profile, name, killer and contributors; a health threshold; placements changed;
  • player.tally counts NPC kills per profile;
  • profiles and placements pushed from the site, as the permission sync is.
• Rust-Link: routes for profiles and placements, and the frames forwarded.
• Module-Rust:
  • an NPC profiles admin page (per server, shared or fleet-wide) with the kit check;
  • a placements view per server;
  • rust.npc.place takes a profile, through a new option source rust.options.npc_profiles;
  • triggers rust.npc.died and rust.npc.health, so a phase can wait for "8 guards died" (waves) or "the boss below 50%";
  • per-profile stats and titles.
• Installer and egg:
  • RunicNPC becomes a third artefact in the Rust bundle, pinned and checksummed like the plugin and the sidecar (D224);
  • doctor reports it missing or edited;
  • the egg installs it.

The wire changes join protocol 13 if it is still unreleased, or open 14.

Tested by the usual trio: each repository's suites, both rigs through the site, and a browser walk of both new pages. An event run places profile NPCs, waves advance on their deaths, and teardown removes them.

Stage 5 — Behaviour

Guard, patrol and escort roles; factions (between profiles, with Rust's scientists, and with teams or clans); group alert; zone tethering; turrets; the weapon behaviours a kit's items imply; TruePVE compatibility.

Tested by harness fights between profiles on the rig (who shoots whom, with what, and within which leash), and an in-game walk for escort and faction ties to a clan.

Stage 6 — Roles

Bosses (a health bar drawn with CUI, phases at thresholds that swap profile values, announcements through the bridge to engagement, a reward on the kill through the existing reward verbs) and passive NPCs (press E, site-written lines).

Tested by an in-game walk (the bar, a phase change, the announcement arriving on Discord and in the app), and the site's trigger firing at the threshold.

Stage 7 — Loot

Loot tables authored on the site, the corpse's default loot cleared or kept, a crate on death, corpse removal.

Tested by harness kills whose corpses are read back, 100 times each, against the table's chances.

Stage 8 — On the map and in the app

Event NPCs and bosses on the live map (protocol 11's map.live), a live "left: 3/8" on the event page, and the same in the Android app.

Tested by a browser walk and an emulator walk.

Stage 9 — Hardening and release

• Performance to the budget stage 1 measured: 100 NPCs on a 6000 map without the frame time crossing it.
• An update drill: a rig on Rust's staging branch loads the current RunicNPC before each forced wipe. The subclass swap and the brain are what break when Rust changes, so they are kept small and listed in one place.
• The whole acceptance walk on both rigs, with a player.
• Operator documentation: docs/runicnpc/ gets INSTALL and a command reference; module-rust's OPERATING notes list it as required.
• Publishing (D224): the Gitea release is the source of record. Other download sites (uMod, Codefling) are decided then, each against its own rules, for example uMod's review guidelines.
• v1.0.0 released, and module-rust then requires it:
  • the bundle lists it;
  • the module refuses NPC steps on a server without it, saying why;
  • the bridge reports it in hello.

Then the Rust plan resumes at PLAN_REDESIGNS §9 item 6 (the step editor and the kit weekend) and §11.

Stage 10 — Custom navigation (only if needed)

§8. Not scheduled.

---

10. Maintenance, honestly

What breaks	When	How we know	Cost
The subclass swap and the brain states	A Rust update that changes ScientistNPC, its brain, or BaseNavigator	The staging-branch rig, before the wipe	Our release timing, not an upstream author's. This is NpcSpawn's churn, but for the states we use, not all of its twenty.
Kits' API	A Kits release that renames GiveKit	Stage 2's harness	Low: one call.
ZoneManager's API	A ZoneManager release	Stage 5's harness	Low, and the tether is optional.
Carbon's compatibility layer	A Carbon release	The Carbon rig	Seen before; recorded in CARBON.md.

A RunicNPC fix ships as its own release. It moves the bundle's pin only when the bridge needs it to, so an NPC fix does not wait for a bridge release, or the reverse.

---

11. Questions for the org lead

All eight were answered on 2026-09-30, as recommended except Q6 (D224 adds Gitea and other download sites) and Q7 (D227: no default caps, a cost warning instead). They are kept as asked.

Q1. Can RunicNPC be used without Runic Gateway? Picture a server owner who installs only RunicNPC, from uMod.

• (a, recommended) Yes. Without a site, profiles live in RunicNPC's data file and console commands edit them. With a site, the site's profiles replace that file on every push, and in-game profile edits are refused with "this server's profiles are managed by its website".
• (b) No. Profiles come only from a site, and the plugin is only ever installed by our installer.

Q2. An admin places three guards with /rnpc place, then the site is offline for a day. What happens?

• (a, recommended) The placements live on the server, so the guards keep respawning. The site catches up when it returns, and shows and edits them from then on.
• (b) The site is the only record, so a placement made while it is offline is refused.

Q3. What should our NPC be?

• (a, recommended) Its own subclass of Rust's scientist with its own brain, as NpcSpawn does. It can be named, and it can guard, escort and run boss phases. The brain is the part a Rust update can break.
• (b) Rust's scientist left as it is, plus small patches for the name and a few values. There is less to break, but there is no guard, escort or boss behaviour.

Q4. A player kills your "Warden" boss. Where does "Warden kills: 3" show?

• (a, recommended) On their public profile and as a title condition, like the NPC kills column today.
• (b) Only to admins.

Q5. Branches. Like the other Rust repositories (D18), build on edge and cut over to main for releases? Recommended: yes.

Q6. How does RunicNPC reach a server?

• (a, recommended) The installer and the egg install it from our bundle, pinned and checksummed like the bridge. Kits and ZoneManager stay "report, don't install" (D153).
• (b) Operators install it themselves, like Kits, and doctor only reports it.

Q7. How many NPCs by default? Recommended defaults, each editable per server:

• 100 NPCs on a server in all;
• 50 per owner (one event run, or all of one admin's placements);
• 10 spawns per second.

Q8. The name. The plugin file is RunicNPC.cs, so its console name is RunicNPC, with the command /rnpc and permissions runicnpc.*. Recommended: yes.