> ## Documentation Index > Fetch the complete documentation index at: https://docs.eucaengine.com/llms.txt > Use this file to discover all available pages before exploring further. # Create entity with optional components ## OpenAPI ````yaml /openapi.json post /spawn openapi: 3.1.0 info: title: Euca Engine API description: >- The typed HTTP API for the agent-native game engine. Local server runs unauthenticated on localhost:3917. license: name: '' version: 1.1.0 servers: - url: http://localhost:3917 security: [] tags: - name: World description: >- Inspect and mutate the live world: status, observe, entities, spawn/despawn, reset. - name: Simulation description: 'Drive the simulation clock: step, play, pause.' - name: Rules description: 'Rules-as-data: register and list gameplay rules.' - name: Gameplay description: >- Match lifecycle and gameplay actions: games, damage/heal, triggers, projectiles, AI, abilities. - name: Discovery and ops description: 'Operational introspection: world health diagnostics and GPU/engine info.' - name: Forks description: Counterfactual 'what-if' simulation on deep-cloned worlds. - name: Snapshots and probes description: Capture, list, and diff labeled world snapshots; probe = advance + assert. - name: Scenes and scenarios description: Persist scenes to disk and apply/export declarative scenario documents. - name: Inventory and economy description: >- Items, inventories, equipment, and the gold economy: define/give/equip items and list a unit inventory. - name: Status effects description: >- Timed buffs/debuffs with stat modifiers and tick effects: apply, list, and cleanse. - name: Templates and prefabs description: >- Reusable spawn definitions: named entity templates and registered prefabs — create, spawn, and list. - name: Assertions and manifest description: >- Testable expectations and sprint contracts: define/evaluate/list/delete assertions and set/read the game manifest. - name: Camera and render description: >- Control the render/editor viewport: camera pose and presets, screenshots, per-entity materials, post-processing, and volumetric fog. - name: UI and HUD description: >- Author the in-game HUD overlay: add text and bars, list, and clear elements. - name: Animation description: >- Skeletal animation: load clips, play/stop on entities, list the library, and attach state machines and montages. - name: Audio description: Play and stop global or spatial sound sources, and list the active ones. - name: Particles description: 'Particle emitters: create, stop, and list GPU/CPU emitter entities.' - name: Terrain and foliage description: Heightmap terrain create/edit and instanced foliage scatter/list. - name: Navigation description: >- Navmesh generation and A* pathfinding: build navmesh, compute paths, and set entity path goals. - name: Input description: >- Input bindings and context stack: bind/unbind keys to actions, list bindings, and push/pop input contexts. - name: Scripting description: 'Lua scripting: attach scripts to entities and list scripted entities.' - name: Assets description: >- AI-powered 3D asset generation: start jobs, poll status, and list tasks and providers. - name: Auth description: >- Optional session auth for hosted deployments; the local server is unauthenticated. paths: /spawn: post: tags: - World summary: Create entity with optional components operationId: spawn requestBody: content: application/json: schema: $ref: '#/components/schemas/SpawnRequest' required: true responses: '201': description: Entity spawned. content: application/json: schema: $ref: '#/components/schemas/SpawnResponse' example: entity_generation: 0 entity_id: 1 components: schemas: SpawnRequest: type: object properties: agent_id: type: - integer - 'null' format: int32 minimum: 0 ai_patrol: type: - array - 'null' items: type: array items: type: number format: float description: AI patrol waypoints as colon-separated "x,y,z:x,y,z" building_type: type: - string - 'null' description: >- Building type (e.g. "tier1_tower", "melee_barracks", "ancient"). When set, attaches BuildingStats, BackdoorProtection, and TowerAggro. collider: oneOf: - type: 'null' - $ref: '#/components/schemas/ColliderData' color: type: - string - 'null' combat: type: - boolean - 'null' combat_cooldown: type: - number - 'null' format: float combat_damage: type: - number - 'null' format: float combat_range: type: - number - 'null' format: float combat_speed: type: - number - 'null' format: float combat_style: type: - string - 'null' description: '"melee" (default) or "stationary" (towers)' gold: type: - integer - 'null' format: int32 description: Starting gold gold_bounty: type: - integer - 'null' format: int32 description: Gold bounty awarded to killer health: type: - number - 'null' format: float lane: type: - string - 'null' description: 'Lane assignment for buildings: "top", "mid", or "bot".' mesh: type: - string - 'null' physics_body: type: - string - 'null' player: type: - boolean - 'null' description: Mark this entity as the player-controlled hero position: type: - array - 'null' items: type: number format: float role: type: - string - 'null' description: 'Entity role: hero, minion, tower, structure' scale: type: - array - 'null' items: type: number format: float spawn_point: type: - integer - 'null' format: int32 description: Spawn point for team (marks this entity as a respawn location) minimum: 0 team: type: - integer - 'null' format: int32 minimum: 0 velocity: oneOf: - type: 'null' - $ref: '#/components/schemas/VelocityData' xp_bounty: type: - integer - 'null' format: int32 description: XP bounty awarded to killer minimum: 0 SpawnResponse: type: object required: - entity_id - entity_generation properties: entity_generation: type: integer format: int32 minimum: 0 entity_id: type: integer format: int32 minimum: 0 ColliderData: oneOf: - type: object required: - hx - hy - hz - shape properties: hx: type: number format: float hy: type: number format: float hz: type: number format: float shape: type: string enum: - Aabb - type: object required: - radius - shape properties: radius: type: number format: float shape: type: string enum: - Sphere - type: object required: - radius - half_height - shape properties: half_height: type: number format: float radius: type: number format: float shape: type: string enum: - Capsule - type: object description: >- Convex hull, referenced by its registry handle (the geometry itself lives in the `ConvexHullRegistry`, not the API payload). required: - hull - shape properties: hull: type: integer format: int32 minimum: 0 shape: type: string enum: - Convex - type: object description: Static triangle mesh, referenced by its `TriMeshRegistry` handle. required: - mesh - shape properties: mesh: type: integer format: int32 minimum: 0 shape: type: string enum: - TriMesh - type: object description: >- Compound of convex parts (a convex decomposition), each referenced by its `ConvexHullRegistry` handle. The geometry lives in the registry, not here. required: - parts - shape properties: parts: type: array items: type: integer format: int32 minimum: 0 shape: type: string enum: - Compound VelocityData: type: object required: - linear properties: angular: type: array items: type: number format: float linear: type: array items: type: number format: float ````