# OpenAI Realtime reference brain — Python (slice-3 spec §7.5)

A Python implementation of the slice-3 OpenAI Realtime brain — the canonical
foreign-language brain demo, hand-rolled from the documented tap protocol
([`docs/superpowers/specs/2026-06-30-slice-3-realtime-brain-design.md`](../../docs/superpowers/specs/2026-06-30-slice-3-realtime-brain-design.md)).

## Why

Proves the slice-3 tap protocol extension is language-agnostic. A Python
script speaking JSON-via-WSS matches the OpenAI-Realtime-related portions of
the spec without depending on Rust code paths. Same rationale as slice-2's
Python echo brain — the project's `examples/` dir is the home for canonical
foreign-language brain demos.

The structure mirrors the Rust `rutster-brain-realtime` crate: a WS server
(the tap side the core dials into) bridged bidirectionally to a WS client
(the OpenAI Realtime side). The event mapping is the spec §4.2 table verbatim.

## Run

```bash
pip install -r requirements.txt
OPENAI_API_KEY=sk-... python examples/openai_realtime_brain/openai_realtime_brain.py
```

The Python brain binds the tap WS server on `RUTSTER_BRAIN_BIND` (default
`127.0.0.1:8082`). The rutster binary, started normally (`cargo run`), dials
out to `RUTSTER_TAP_URL` (default `ws://127.0.0.1:8082/realtime` — set
`RUTSTER_TAP_URL=ws://127.0.0.1:8082` to match the Python brain's bind).

Other env vars:

| Var | Default | Purpose |
|---|---|---|
| `OPENAI_API_KEY` | (required) | OpenAI auth |
| `RUTSTER_BRAIN_BIND` | `127.0.0.1:8082` | host:port for the tap WS server |
| `OPENAI_REALTIME_MODEL` | `gpt-4o-realtime` | OpenAI model query-param |
| `OPENAI_REALTIME_VOICE` | `alloy` | Voice passed in `session.update` |

## Dependencies

Only `websockets>=12.0` — both the tap-side server and the OpenAI-side client
speak plain WSS, so the `openai` Python SDK is not needed (the spec §4.2
mapping is explicit enough to hand-roll against the wire). This is a
deliberate simplification over the slice-3 plan skeleton, which imported the
SDK but never used it.

## Not in CI

Per AGENTS.md's "no Python in the dev loop" rule. The slice-3 integration
test uses `rutster-brain-realtime --features=mock` — the in-process Rust
mock — not this Python file.