Which ComfyUI HTTP routes only read state and which change or destroy it (queue, history, files, loaded models), and what is a safe first sequence of calls on a server I did not start?

At the pin, server.py registers 28 decorated routes, each also reachable under /api. Reads: GET /prompt, /queue, /history[/id], /api/jobs[/id], /system_stats, /features, /object_info, /view and model/extension listings. State changers: POST /prompt, /queue, /interrupt, /free, /history, /upload/image, /upload/mask and the jobs cancel endpoints. POST /interrupt without a prompt_id stops whatever is running, which may be another user's job; prefer an id-scoped cancel. The docs table is incomplete and gives POST /queue a broader meaning than the code. Curator qualifications: Verified: POST /queue touches only pending items; bare /interrupt stops whatever is running; there is no owner check in these handlers. The docs-vs-code conflict (POST /queue 'pending/running') is genuine. Scope: '28 routes' means server.py decorators only. The full HTTP surface also includes userdata, internal, model-file, custom-node and asset routes registered from other modules, so a 'safe first sequence' list is incomplete for those. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://github.com/Comfy-Org/docs/blob/506a4a94db30524adb8706667aec050d71dbdf60/development/comfyui-server/comms_routes.mdx",
      "note": "post_queue L1244-L1255; post_interrupt L1257-L1291; wipe_queue L1400; delete_queue_item L1405; head"
    },
    {
      "url": "https://github.com/Comfy-Org/ComfyUI/blob/1a82e6d01f395b43275c77acd289af1eb7090bb9/server.py",
      "note": "post_queue L1244-L1255; post_interrupt L1257-L1291; wipe_queue L1400; delete_queue_item L1405; head"
    },
    {
      "url": "https://github.com/Comfy-Org/ComfyUI/blob/1a82e6d01f395b43275c77acd289af1eb7090bb9/comfy/cli_args.py",
      "note": "post_queue L1244-L1255; post_interrupt L1257-L1291; wipe_queue L1400; delete_queue_item L1405; head"
    }
  ]
}