## Description
This PR makes `thread.history_mode` immutable after the thread's
canonical first `SessionMeta` has been written. Later same-thread
`SessionMeta` lines are compatibility metadata writes, not a new thread
definition.
Without this, an older binary could append a `SessionMeta` that omits
`history_mode`; when a newer binary replays it, serde defaults that
missing field to `legacy` and SQLite could downgrade a paginated thread.
## Why
`history_mode` is the persisted thread storage contract.
Paginated-thread fail-closed behavior and SQLite memory filtering depend
on it staying aligned with canonical rollout metadata, especially when
multiple Codex binary versions can touch the same local rollout.
## What changed
- Stop generic rollout metadata replay from overwriting `history_mode`
from later `SessionMeta` items.
- Remove `history_mode` from `ThreadMetadataPatch`, so mutable metadata
sync and app-server metadata updates cannot rewrite it.
- When local metadata sync has to recreate a missing SQLite row, recover
`history_mode` from the rollout's canonical first `SessionMeta` instead
of from a mutable patch.
- Keep the in-memory thread store using the created thread's canonical
`history_mode` instead of metadata patches.
- Fill the one remaining core test `CreateThreadParams` initializer with
the new `history_mode` field; Bazel CI caught this after the parent
history-mode PR landed.
## Validation
- `just fmt`
- `just test -p codex-thread-store`
- `just test -p codex-state
session_meta_does_not_set_model_or_reasoning_effort`
## Description
This PR adds a new `historyMode = "legacy" | "paginated"` to `Thread`.
This will be stored in `SessionMeta` in the JSONL rollout file and as a
new column in the SQLite thread_metadata table, and exposed on
`thread/start` and on the `Thread` object in app-server.
## What changed
- Added canonical `ThreadHistoryMode` with `legacy` and `paginated`,
defaulting old and new SessionMeta to `legacy`.
- Carried `history_mode` through core session config, ThreadStore stored
metadata, local/in-memory stores, rollout metadata extraction, and the
existing SQLite `threads` table.
- Added experimental `historyMode` to app-server v2 `Thread` and
`thread/start`.
- Made paginated stored threads metadata-discoverable but unsupported
for legacy full-history reads, `load_history`, live resume, and create
paths.
- Regenerated app-server schema fixtures and added
protocol/state/thread-store/app-server coverage for persistence and
fail-closed behavior.
## Compatibility floor
Because users may be running various versions of Codex binaries on the
same machine (TUI, Codex App, etc.), we will need to establish a
compatibility floor for upcoming paginated threads, which will change
how thread storage reads and writes work.
The overall plan here:
```
Release N:
- Add historyMode to SessionMeta / Thread / SQLite metadata.
- Teach binaries to understand paginated threads.
- If a binary sees `historyMode="paginated"` but does not support the paginated contract, it refuses to resume/mutate the thread.
- Default remains `"legacy"`.
Release N+1:
- First-party clients start opting into paginated threads where appropriate.
- Internal dogfood / staged rollout.
- Measure old-client usage and paginated-thread unsupported errors.
Release N+2:
- Only after Release N+ is overwhelmingly deployed, make paginated the default.
- Accept that a small tail of N-1-or-older binaries may not understand paginated threads.
```
The important behavior change is fail-closed handling for a binary that
encounters a persisted `paginated` thread before it knows how to fully
support paginated history. In app-server, if a thread is `paginated`, we
will:
- allow metadata-only discovery paths like `thread/list` and
`thread/read(includeTurns=false)`, so clients can still see the thread
and inspect its `historyMode`
- reject legacy full-history/live-thread paths like
`thread/read(includeTurns=true)` and `thread/resume` with an unsupported
JSON-RPC error
- avoid silently treating an unknown or future `historyMode` as `legacy`
Under the hood, the ThreadStore layer also rejects legacy operations
that would need to load or replay the full thread history for a
paginated thread. That gives us the behavior we want for Release N:
future paginated threads are visible, but this binary fails closed
instead of trying to operate on them as if they were legacy threads.
- Add 1%-sampled rollout persistence metrics that report per-item and
per-thread JSON byte totals before and after filtering when metrics
export is enabled.
- Tag each item with its exact response or event variant, including
nested turn-item kinds for conditionally persisted completion events, so
aggregate cloud-storage impact can be estimated by policy choice.
Move the application of the persistence policy into the thread store, so
thread stores can get raw append items rather than canonical append
items. This will enable store-specific projections over the raw input
items.
## Why
Local rollout compression needs a cold `.jsonl.zst` representation
without letting compressed physical paths leak into append-mode writers.
The unsafe case is resume or metadata update code successfully reading a
compressed rollout and then appending raw JSONL bytes to the zstd file.
This PR folds the former #25088 materialization slice into the
read-support PR so the reader changes and append-safety invariant land
together.
## What Changed
- Teach rollout readers, discovery, listing, search, and ID lookup to
understand compressed `.jsonl.zst` rollouts.
- Keep `.jsonl` as the logical/stored rollout path while allowing read
paths to open either plain or compressed storage.
- Materialize compressed rollouts back to plain `.jsonl` before
append-mode writes, including resume and direct metadata append paths.
- Preserve compressed-file permissions when materializing back to plain
JSONL.
- Refresh thread-store resolved rollout paths after compatibility
metadata writes so reconciliation follows the materialized file.
- Avoid treating transient compression temp files as real rollout lookup
results.
## Remaining Stack
#25089 remains the separate worker PR. It is based directly on this PR
and stays behind the disabled `local_thread_store_compression` feature
flag.
The worker still has a broader coordination question: a resume or
metadata update can race with background compression while a plain file
is being replaced by `.jsonl.zst`. This PR handles the read and
materialize-before-append primitives; it does not make the worker
production-ready.
## Validation
- `just test -p codex-rollout`
- `just test -p codex-thread-store`
- `just fix -p codex-rollout`
- `just fix -p codex-thread-store`
- `just bazel-lock-check`
- make ThreadStore::update_thread_metadata accept a broad range of
metadata patches
- keep ThreadStore::append_items as raw canonical history append (no
metadata side effects)
- in the local store, write these metadata updates to a combination of
sqlite and rollout jsonl files for backwards-compat. It special cases
which fields need to go into jsonl vs sqlite vs whatever, confining the
awkwardness to just this implementation
- in remote stores we can simply persist the metadata directly to a
database, no special casing required.
- move the "implicit metadata updates triggered by appending rollout
items" from the RolloutRecorder (which is local-threadstore-specific) to
the LiveThread layer above the ThreadStore, inside of a private helper
utility called ThreadMetadataSync. LiveThread calls ThreadStore
append_items and update_metadata separately.
- Add a generic update metadata method to ThreadManager that works on
both live threads and "cold" threads
- Call that ThreadManager method from app server code, so app server
doesn't need to worry about whether the thread is live or not
## Why
Reverts #20689 to restore the previous optional state DB plumbing. The
conflict resolution keeps the newer installation ID and session/thread
identity changes that landed after #20689, while removing the mandatory
state DB and agent graph store dependency from ThreadManager
construction.
## What changed
- Restored `Option<StateDbHandle>` through app-server, MCP server,
prompt debug, and test entry points.
- Removed the `codex-core` dependency on `codex-agent-graph-store` and
reverted descendant lookup back to the existing state DB path when
available.
- Kept newer `installation_id` forwarding by passing it beside the
optional DB handle.
- Kept local thread-name updates working when the optional state DB
handle is absent.
## Validation
- `git diff --check`
- `cargo test -p codex-thread-store`
- `cargo test -p codex-state -p codex-rollout -p
codex-app-server-protocol`
- Attempted `env CARGO_INCREMENTAL=0 cargo test -p codex-core -p
codex-app-server -p codex-app-server-client -p codex-mcp-server -p
codex-thread-manager-sample -p codex-tui`; blocked locally by a rustc
ICE while compiling `v8 v146.4.0` with `rustc 1.93.0 (254b59607
2026-01-19)` on `aarch64-apple-darwin`.
## Why
We want the agent graph store to be passed down the stack as a real
dependency, the same way we already treat the thread store.
This will let us inject the agent graph store as a real dependency and
support implementations other than the local SQLite-backed one. Right
now most code instantiates a state DB and an agent graph store
just-in-time. Ideally, we would not depend on the state DB directly but
only read through the higher-level interfaces.
This change makes the dependency boundaries explicit and moves state DB
initialization to process bootstrap instead of hiding it inside local
store implementations.
## What changed
- `ThreadManager` now requires a `StateDbHandle` and an
`AgentGraphStore` at construction time instead of treating them as
optional internals.
- The local store constructors no longer lazily initialize SQLite.
Callers now initialize the state DB once per process and use that shared
handle to build:
- `LocalThreadStore`
- `LocalAgentGraphStore`
- App bootstraps (`app-server`, `mcp-server`, `prompt_debug`, and the
thread-manager sample) now initialize the state DB up front and inject
the resulting handle down the stack.
- `app-server` now consistently uses its process-scoped state DB handle
instead of reopening SQLite or trying to recover it from loaded threads.
- Device-key storage now reuses the shared state DB handle instead of
maintaining its own lazy opener.
- The thread archive / descendant traversal paths now use the injected
`AgentGraphStore` instead of reaching through local
thread-store-specific state.
## Verification
- `cargo check -p codex-core -p codex-thread-store -p codex-app-server
-p codex-mcp-server -p codex-thread-manager-sample --tests`
- `cargo test -p codex-thread-store`
- `cargo test -p codex-core
thread_manager_accepts_separate_agent_graph_store_and_thread_store --
--nocapture`
- `cargo test -p codex-app-server
thread_archive_archives_spawned_descendants -- --nocapture`
- Build one app-server process ThreadStore from startup config and share
it with ThreadManager and CodexMessageProcessor.
- Remove per-thread/fork store reconstruction so effective thread config
cannot switch the persistence backend.
- Add params to ThreadStore create/resume for specifying thread
metadata, since otherwise the metadata from store creation would be used
(incorrectly).
Begin migrating the thread write codepaths to ThreadStore.
This starts using ThreadStore inside of core session code, not only in
the app server code.
Rework the interfaces around thread recording/persistence. We're left
with the following:
* `ThreadManager`: owns the process-level registry of loaded threads and
handles cross-thread orchestration: start, resume, fork, lookup, remove,
and route ops to running CodexThreads.
* `CodexThread`: represents one loaded/running thread from the outside.
It is the handle app-server and callers use to submit ops, inspect
session metadata, and shut the thread down.
* `LiveThread`: session-owned persistence lifecycle handle for one
active thread. Core session code uses it to append rollout items,
materialize lazy persistence, flush, shutdown, discard init-failed
writers, and load that thread’s persisted history.
* `ThreadStore`: storage backend abstraction. It answers “how are
threads persisted, read, listed, updated, archived?” Local and remote
implementations live behind this trait.
* `LocalThreadStore`: local ThreadStore implementation. It owns the
file/sqlite-specific details and keeps RolloutRecorder as a local
implementation detail.
This is a few too many Thread abstractions for my liking, but they do
all represent different concepts / needs / layers.
Migration note: in places where the core code explicitly requires a
path, rather than a thread ID, throw an error if we're running with a
remote store.
Cover the new local live-writer lifecycle with focused tests and
preserve app-server thread-start behavior, including ephemeral pathless
sessions.
Owen Lin