411276bfde
- Integration test: smoke test against in-process EchoServer (hello handshake round-trip). Full end-to-end + reconnect-path tests adapt to slice-1's existing integration-test harness. - examples/echo_brain/: Python reference brain (~80 lines, websockets lib). README documents runtime posture + why a Python brain complements the Rust one (language-agnosticism vs wire-types-reusability). - LEARNING.md: 5 new pointers (mpsc/oneshot, VecDeque ring, async WS, Box<dyn Trait> field widening, zero-sized marker newtype). Spec ref: 2026-06-28-slice-2-agent-tap-design.md §8.4, §8.5 #7.
Rutster Echo Brain (Python reference)
The canonical foreign-language brain for slice-2. Speaks the slice-2 tap wire
protocol (§3):
versioned JSON events over ws:// text frames with base64-encoded
little-endian PCM.
Why a Python brain?
The architecture (ARCHITECTURE.md §"Agent tap") names "a Python script" as the
canonical brain persona. This example proves the wire format is language-agnostic:
the core's rutster-tap Rust types serialize/deserialize to exactly what
json.loads + websockets produces. The Rust echo brain (crates/rutster-tap-echo)
proves wire-types reusability from outside the core; this Python brain proves
language-agnosticism.
Run
pip install -r examples/echo_brain/requirements.txt
python examples/echo_brain/echo_brain.py
# [echo_brain] listening on ws://127.0.0.1:8081/echo
Then in another terminal:
cargo run # the core dials out to ws://127.0.0.1:8081/echo by default
Not in CI
This script is not run by CI. The Rust rutster-tap-echo crate covers
the in-process test surface for the integration test; this Python brain is
the human-runnable demo + manual e2e test plan.
Protocol
See the spec §3 for the full wire protocol. Key behavior:
- On
hello: ack withhello(echo thesession_id). - On
audio_in: echo the same PCM back asaudio_out(advisory — core disposes). - On
bye/session_end: close cleanly. - Stateless across reconnects (spec §5.3) — every
hellostarts fresh.