> ## Documentation Index
> Fetch the complete documentation index at: https://www.agentworldprotocol.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Scene graphs

> The optional semantic channel: entities, affordances, relations.

Worlds SHOULD expose a semantic channel (`modality: text/event+json`, conventionally `scene`) publishing a structured world model — the highest-leverage feature for LLM agents.

```json theme={null}
{
  "entities": [
    { "id": "box_12", "class": "container", "pose": { "frame": "world", "p_m": [1.2, 0.4, 0.0], "q": [0,0,0,1] },
      "affordances": ["graspable", "openable"],
      "state": { "open": false }, "controlled_by": null }
  ],
  "relations": [ { "type": "on_top_of", "subject": "box_12", "object": "table_1" } ]
}
```

* Entity `id`s MUST be stable for the life of an entity and never reused within a session. `[AWP-SCN-001]`
* `affordances` values SHOULD correspond to granted action types where the mapping exists (e.g. `graspable` ↔ `grasp`). `[AWP-SCN-002]`
* Scene frames are full snapshots (keyframes) or deltas per [observation rules](/spec/loop/observations). `[AWP-SCN-003]`