## Why
Remote compaction v2 is the `/responses` implementation of
session-history compaction, but it still needs to preserve the
observable contract of the legacy `/responses/compact` path. In
particular, users and integrations that rely on `PreCompact` and
`PostCompact` hooks should not see different behavior when
`remote_compaction_v2` is enabled.
## What Changed
- Runs `PreCompact` before issuing the remote compaction v2 request,
including `Interrupted` analytics when a pre-hook stops execution.
- Runs `PostCompact` after a successful v2 compaction and aborts the
turn if the post-hook stops execution.
- Adds `compact_remote_parity` coverage that compares legacy and v2
compaction across manual transcript shapes, automatic pre-turn
compaction, automatic mid-turn compaction, hook payloads, replacement
history, follow-up request payloads, and API-key `service_tier=fast`
behavior.
- Registers the new parity suite under `core/tests/suite`.
Relevant code:
-
[`compact_remote_v2.rs`](https://github.com/openai/codex/blob/af63745cb502183a6fc447d0240f8150934d70b7/codex-rs/core/src/compact_remote_v2.rs)
-
[`compact_remote_parity.rs`](https://github.com/openai/codex/blob/af63745cb502183a6fc447d0240f8150934d70b7/codex-rs/core/tests/suite/compact_remote_parity.rs)
## Verification
- Added `core/tests/suite/compact_remote_parity.rs` to assert parity
between legacy remote compaction and remote compaction v2 for the
affected request, hook, rollout-history, and follow-up paths.
- Existing `compact_remote_v2` unit coverage still exercises v2
replacement-history retention and compaction-output collection.
## Why
Remote compaction v2 was still using `context_compaction` as both the
request trigger and the compacted output shape. The Responses API now
has the landed contract for this flow: Codex sends a dedicated `{
"type": "compaction_trigger" }` input item, and the backend returns the
standard `compaction` output item with encrypted content.
This aligns the v2 path with that wire contract while preserving the
existing local compacted-history post-processing behavior.
## What changed
- Add `ResponseItem::CompactionTrigger` and regenerate the app-server
protocol schema fixtures.
- Send `compaction_trigger` from `remote_compaction_v2` instead of a
payload-less `context_compaction`.
- Collect exactly one backend `compaction` output item, then reuse the
existing compacted-history rebuilding path.
- Treat the trigger item as a transient request marker rather than model
output or persisted rollout/memory content.
## Verification
- `cargo test -p codex-protocol compaction_trigger`
- `cargo test -p codex-core remote_compact_v2`
- `cargo test -p codex-core compact_remote_v2`
- `cargo test -p codex-core
responses_websocket_sends_response_processed_after_remote_compaction_v2`
- `just write-app-server-schema`
- `cargo test -p codex-app-server-protocol schema_fixtures`
## Why
Recent session history showed no active use of the raw `shell`,
`local_shell`, or `container.exec` execution surfaces. Keeping those
handlers/specs wired into core leaves duplicate shell execution paths
alongside the supported `shell_command` and unified exec tools.
## What changed
- Removed the raw `shell` handler/spec and its `ShellToolCallParams`
protocol helper.
- Removed the legacy `local_shell` and `container.exec` handler/spec
plumbing while preserving persisted-history compatibility for old
response items.
- Normalized model/config `default` and `local` shell selections to
`shell_command`.
- Pruned tests that exercised removed raw-shell/local-shell/apply-patch
variants and kept coverage on `shell_command`, unified exec, and
freeform `apply_patch`.
## Verification
- `git diff --check`
- `cargo test -p codex-protocol`
- `cargo test -p codex-tools`
- `cargo test -p codex-core tools::handlers::shell`
- `cargo test -p codex-core tools::spec`
- `cargo test -p codex-core tools::router`
- `cargo test -p codex-core
active_call_preserves_triggering_command_context`
- `cargo test -p codex-core guardian_tests`
- `cargo test -p codex-core --test all shell_serialization`
- `cargo test -p codex-core --test all apply_patch_cli`
- `cargo test -p codex-core --test all shell_command_`
- `cargo test -p codex-core --test all local_shell`
- `cargo test -p codex-core --test all otel::`
- `cargo test -p codex-core --test all hooks::`
- `just fix -p codex-core`
- `just fix -p codex-tools`
## Why
Remote compaction v2 consumes a normal Responses stream, but that
compaction-specific stream consumer dropped the `response.completed` id.
As a result, the `responses_websocket_response_processed` lifecycle
notification was emitted for normal turn sampling but not after a v2
remote compaction response was fully processed.
## What changed
- Return the completed response id alongside the v2 `context_compaction`
output item.
- After v2 compacted history is installed, send `response.processed`
through the same websocket session when the feature is enabled.
- Add websocket regression coverage for a remote compaction v2 request
followed by `response.processed`.
## Verification
- `cargo test -p codex-core --test all
responses_websocket_sends_response_processed_after_remote_compaction_v2
-- --nocapture`
- `cargo test -p codex-core
collect_context_compaction_output_accepts_additional_output_items --
--nocapture`
## Why
This adds the `remote_compaction_v2` client path so remote compaction
can run through the normal Responses stream and install a
`context_compaction` item that trigger a compaction.
The goal is to migrate some of the compaction logic on the client side
We keeps the v2 transport behind a feature flag while letting follow-up
requests reuse the compacted context instead of falling back to the
legacy compaction item shape.
## What changed
- add `ResponseItem::ContextCompaction` and refresh the generated
app-server / schema / TypeScript fixtures that expose response items on
the wire
- add `core/src/compact_remote_v2.rs` to send compaction through the
standard streamed Responses client, require exactly one
`context_compaction` output item, and install that item into compacted
history
- route manual compact and auto-compaction through the v2 path when
`remote_compaction_v2` is enabled, while keeping the existing remote
compaction path as the fallback
- preserve the new item type across history retention, follow-up request
construction, telemetry, rollout persistence, and rollout-trace
normalization
- add targeted coverage for the feature flag, `context_compaction`
serialization, rollout-trace normalization, and remote-compaction
follow-up behavior
## Verification
- added protocol tests for `context_compaction`
serialization/deserialization in `protocol/src/models.rs`
- added rollout-trace coverage for `context_compaction` normalization in
`rollout-trace/src/reducer/conversation_tests.rs`
- added remote compaction integration coverage for v2 follow-up reuse
and mixed compaction output streams in
`core/tests/suite/compact_remote.rs`
---------
Co-authored-by: Codex <noreply@openai.com>