## Summary
This PR aims to improve integration between the realtime model and the
codex agent by sharing more context with each other. In particular, we
now share full realtime conversation transcript deltas in addition to
the delegation message.
realtime_conversation.rs now turns a handoff into:
```
<realtime_delegation>
<input>...</input>
<transcript_delta>...</transcript_delta>
</realtime_delegation>
```
## Implementation notes
The transcript is accumulated in the realtime websocket layer as parsed
realtime events arrive. When a background-agent handoff is requested,
the current transcript snapshot is copied onto the handoff event and
then serialized by `realtime_conversation.rs` into the hidden realtime
delegation envelope that Codex receives as user-turn context.
For Realtime V2, the session now explicitly enables input audio
transcription, and the parser handles the relevant input/output
transcript completion events so the snapshot includes both user speech
and realtime model responses. The delegation `<input>` remains the
actual handoff request, while `<transcript_delta>` carries the
surrounding conversation history for context.
Reviewers should note that the transcript payload is intended for Codex
context sharing, not UI rendering. The realtime delegation envelope
should stay hidden from the user-facing transcript surface, while still
being included in the background-agent turn so Codex can answer with the
same conversational context the realtime model had.
- Add outputModality to thread/realtime/start and wire text/audio output
selection through app-server, core, API, and TUI.\n- Rename the realtime
transcript delta notification and add a separate transcript done
notification that forwards final text from item done without correlating
it with deltas.
Rename the Realtime V2 delegation tool and parser constant to
background_agent, and update the tool description and fixtures to match.
Validation: just fmt; cargo check -p codex-api; git diff --check
---------
Co-authored-by: Codex <noreply@openai.com>
Summary:
- parse the realtime call Location header and join that call over the
direct realtime WebSocket
- keep WebRTC starts alive on the existing realtime conversation path
Validation:
- just fmt
- git diff --check
- cargo check -p codex-api
- cargo check -p codex-core --tests
- local cargo tests not run; relying on PR CI
## Summary
- reduce public module visibility across Rust crates, preferring private
or crate-private modules with explicit crate-root public exports
- update external call sites and tests to use the intended public crate
APIs instead of reaching through module trees
- add the module visibility guideline to AGENTS.md
## Validation
- `cargo check --workspace --all-targets --message-format=short` passed
before the final fix/format pass
- `just fix` completed successfully
- `just fmt` completed successfully
- `git diff --check` passed
## Stack Position
2/4. Built on top of #14828.
## Base
- #14828
## Unblocks
- #14829
- #14827
## Scope
- Port the realtime v2 wire parsing, session, app-server, and
conversation runtime behavior onto the split websocket-method base.
- Branch runtime behavior directly on the current realtime session kind
instead of parser-derived flow flags.
- Keep regression coverage in the existing e2e suites.
---------
Co-authored-by: Codex <noreply@openai.com>
- add experimental_realtime_ws_mode (conversational/transcription) and
plumb it into realtime conversation session config
- switch realtime websocket intent and session.update payload shape
based on mode
- update config schema and realtime/config tests
---------
Co-authored-by: Codex <noreply@openai.com>
- Add a feature-flagged realtime v2 parser on the existing
websocket/session pipeline.
- Wire parser selection from core feature flags and map the codex
handoff tool-call path into existing handoff events.
---------
Co-authored-by: Codex <noreply@openai.com>
- migrate the realtime websocket transport to the new session and
handoff flow
- make the realtime model configurable in config.toml and use API-key
auth for the websocket
---------
Co-authored-by: Codex <noreply@openai.com>
- Introduce `RealtimeConversationManager` for realtime API management
- Add `op::conversation` to start conversation, insert audio, insert
text, and close conversation.
- emit conversation lifecycle and realtime events.
- Move shared realtime payload types into codex-protocol and add core
e2e websocket tests for start/replace/transport-close paths.
Things to consider:
- Should we use the same `op::` and `Events` channel to carry audio? I
think we should try this simple approach and later we can create
separate one if the channels got congested.
- Sending text updates to the client: we can start simple and later
restrict that.
- Provider auth isn't wired for now intentionally
## Summary
- add realtime websocket client transport in codex-api
- send session.create on connect with backend prompt and optional
conversation_id
- keep session.update for prompt changes after connect
- switch inbound event parsing to a tagged enum (typed variants instead
of optional field bag)
- add a websocket e2e integration test in
codex-rs/codex-api/tests/realtime_websocket_e2e.rs
## Why
This moves the realtime transport to an explicit session-create
handshake and improves protocol safety with typed inbound events.
## Testing
- Added e2e integration test coverage for session create + event flow in
the API crate.
