## Why
Bounding collected output also requires limiting the raw event backlog between
V8 and the cell actor. Previously, runtime events and cell output accumulated
in an unbounded channel and vector.
## What changed
- Select the event transport and `OutputCollector` from the cell's
`output_truncation` mode. Server mode uses an ordered, bounded channel with
backpressure; client mode retains untruncated output.
- Transfer the collector with each observation and restore it on failed
delivery, preserving retained media and omission metadata.
- Include server-mode script errors in the observation's output budget. Build
completion output only after completion wins against termination, so a
rejected error cannot evict output returned by termination.
- Keep the public service on client-side truncation.
## Testing
Add regression coverage for channel backpressure, event ordering, receiver
closure, failed observation delivery, termination during completion commit,
and oversized errors across UTF-8 and omission boundaries.
GitOrigin-RevId: 7604b60416e33c636ca41138be65dc0fd452774a
## Why
A catchable exception lets JavaScript continue after `exit()`, including in `catch`, `finally`, and queued promise callbacks. Exiting should finish the cell successfully without further output or state changes.
## What changed
- Terminate V8 execution when `exit()` is called and complete the cell even if its module promise remains pending.
- Guard host callbacks against effects after exit, including when getters or value conversion request exit.
- Preserve stored writes made before exit and suppress errors when exit occurs during exception formatting.
## Testing
Add regression tests for synchronous and asynchronous exit, timers, parallel promises, value conversion, exception getters, and resuming after a yield and tool response. Verify that only prior output and stored writes survive, and separately exercise host guards while JavaScript continues running.
GitOrigin-RevId: e9487ba65ef0358612c5009bd26953b786a12798
## Why
Reentering V8 during termination can replace uncatchable cancellation with a catchable JavaScript exception, allowing a script to continue after cancellation.
## What changed
Skip JSON conversion and exception throwing while V8 execution is terminating, preserving cancellation through `image()` getters and JSON fallback.
## Testing
Add regression coverage for cancellation during JSON fallback and reentrant image getters, including prompt termination through the standalone host and continued usability of another session. Extend serialization error tests to cover failing image getters alongside circular JSON.
GitOrigin-RevId: f03dd131a62724106fad96111292ddf5b9dc99f6
## Why
JavaScript objects containing Serde's reserved JSON keys can be reinterpreted during deserialization, allowing nested `RawValue` markers to bypass the parser's normal recursion limit.
## What changed
Reject `$serde_json::private::RawValue` and `$serde_json::private::Number` object keys before passing V8's serialized JSON to `serde_json`. Report a `reserved JSON object key` serialization error while continuing to allow marker text in strings and longer keys.
## Testing
Add runtime regression coverage for nested and escaped marker keys, recursion limits, normal JSON conversion, and session recovery without overwriting stored values. Extend the host-backed integration test to verify that stored values remain available across turns after rejection.
GitOrigin-RevId: 27ddce08e1ffe98ec9dffe02473a815ceae2cc89
## What changed
Consume enabled tool definitions and borrow their metadata when installing `tools` and `ALL_TOOLS`, avoiding copies of the tool catalog. Retain only tool names and kinds in runtime callback state, preserving each cell's original callback indices for its lifetime.
GitOrigin-RevId: 62eaf62abce6de1a0cd5cdb3332fbed754a23993
## What changed
Expose two JavaScript globals for consuming results as inputs settle:
- `as_settled(promises)` returns an async iterator of fulfilled and rejected records in settlement order, preserving queued results while the consumer is busy.
- `stream_settled(promises, emit)` delivers those records to a callback, awaiting each invocation and propagating callback errors.
Records include an `index`, a `status`, and either a `value` or a `reason`. Iterable inputs use positional indices; `Map` inputs retain their keys. Both helpers accept promises, thenables, and plain values.
## Testing
Add runtime coverage for ordering, input types, object identity, callback behavior, early iteration exit, and termination. Add stdio and gRPC host tests for partial results across waits, plus a scenario snapshot verifying fulfilled and rejected records reach the model.
GitOrigin-RevId: cddc9f3679ae04f2421e154caa0417afb15f550d
## Why
Creating a cell deep-copies every stored JSON value, including values the cell never loads. Storing a value also duplicates its payload between the cell's local state and pending writes.
## What changed
Use `Arc<JsonValue>` throughout the session store, cell runtime, and completion writes to share immutable payloads. Keep a separate map snapshot for each cell so later commits cannot change its view of stored values.
GitOrigin-RevId: 4535f0f2ed0c8f8cbfb8d24cf1cb44cbc74472b5
## Why
Each `setTimeout` spawned a sleeping thread that remained alive until its delay elapsed, even after `clearTimeout` or cell completion.
## What changed
Replace per-timer threads with Tokio sleep tasks held by `AbortOnDropHandle`, so removing a timeout or dropping the isolate cancels its task. Enter the caller's Tokio runtime on the code mode runtime thread to support scheduling these timers.
## Testing
Add a regression test using virtual time to verify that cleared timers release their tasks, an awaited timer completes, and cell completion cancels remaining timers without emitting their output.
GitOrigin-RevId: 59c7e57ed226cb32633e2d4c25b778cfab2af423
## Why
Tool response delivery handles kept discarded results alive until the cell ended.
## What changed
Add a local V8 handle scope in `resolve_tool_response` so delivery handles are released when response delivery finishes. Live promises continue to retain their results.
## Testing
Add a regression test that verifies a live promise preserves its response through garbage collection and that dropping the promise makes the response collectible before the cell ends.
GitOrigin-RevId: a74e78acae3ec9a465694d7503150aee123792ec
## Why
Passing `undefined` to a tool could fail JSON parsing because V8 stringifies it as the non-JSON text `undefined`.
## What changed
Return no JSON value for JavaScript `undefined`, so explicit `undefined` tool arguments behave like omitted arguments. Attempts to `store` an undefined value report the existing serializability error and preserve the previous stored value.
## Testing
Add regression coverage for storing `undefined` over an existing `null` value, and extend the current-time tool test to cover `{}`, omitted arguments, and explicit `undefined`.
GitOrigin-RevId: 071050ebb2ecc44c8f08453cf8523b4d21728c7e
## Why
Audio models cannot reliably encode tool-generated clips shorter than 25 ms.
## What changed
- Measure the available audio frames in base64-encoded PCM and IEEE float WAV outputs.
- Replace clips under 25 ms with explanatory text while preserving surrounding Code Mode output.
- Leave clips at or above the threshold and unrecognized audio formats unchanged.
## Testing
- Cover the duration boundary across multiple sample rates and all supported `audio()` input forms.
- Verify bounded and truncated WAV chunks, output after `yield_control()`, and end-to-end mixed text and audio output.
GitOrigin-RevId: 342b4bdbc65db4238580f9cdc372763c2576eca5
## Why
Code mode must link against a V8 build with sandbox support, but Windows MSVC
still used upstream non-sandboxed prebuilts and package builds selected the
older release artifact profile.
## What changed
- Enable the `v8_enable_sandbox` feature directly for the code mode runtime.
- Select the `ptrcomp_sandbox_release` archive and bindings in Cargo packaging
and CI, including Windows MSVC release builds.
- Point Bazel's Windows MSVC targets at the sandbox-enabled Codex artifacts and
enable the matching crate feature.
## Testing
Add a runtime test that calls `v8__V8__IsSandboxEnabled()` and verifies that
the linked V8 library has sandbox support enabled.
GitOrigin-RevId: c1b49b44a6ccfea5b5006d69ec7866848d1cddd7
## What changed
- Move the V8 implementation into a dedicated `codex-code-mode-runtime` crate used by `codex-code-mode-host`, removing the embedded runtime fallback from the Codex process.
- Resolve the host executable from the active installation layout and check its availability before selecting tools.
- Fall back to direct tools with a one-time warning when optional code mode is unavailable. Keep `code_mode_only` and `disable_in_process_fallback` configurations fail-closed.
## Testing
- Cover host discovery for standalone and package layouts, including missing hosts and symlinks.
- Verify direct-tool fallback, one-time warnings, and fail-closed code-mode-only behavior.
GitOrigin-RevId: 5aa3c6f1db148b2231fc24089a2ee0e2b00dbddb
Sean Huang