## Why
Older persisted rollouts can contain `input_image.detail` values of
`auto` or `low` from before `ImageDetail` was narrowed to
`high`/`original`. Current deserialization rejects those values, which
can make resume skip later compacted checkpoints and reconstruct an
oversized raw suffix before the next compaction attempt.
Confirmed Sentry reports fixed by this compatibility path:
- [CODEX-1H3F](https://openai.sentry.io/issues/7500642496/)
- [CODEX-1H6N](https://openai.sentry.io/issues/7501025347/)
- [CODEX-1JDP](https://openai.sentry.io/issues/7504549065/)
- [CODEX-1HW6](https://openai.sentry.io/issues/7503407986/)
## Background
[openai/codex#20693](https://github.com/openai/codex/pull/20693) added
image-detail plumbing for app-server `UserInput` so input images could
explicitly request `detail: original`. The Slack discussion behind that
PR was about ScreenSpot / bridge evals where user input images were
resized, while tool output images already had MCP/code-mode ways to
request image detail.
In review, the intended new API surface was narrowed to `high` and
`original`: default to `high`, allow `original` when callers need
unchanged image handling, and avoid encouraging new `auto` or `low`
usage. That policy still makes sense for newly emitted values.
The missing compatibility piece is persisted history. Older rollouts can
already contain `auto` and `low`, and resume reconstructs typed history
by deserializing those rollout records. Rejecting old values at that
boundary causes valid compacted checkpoints to be skipped. This PR
restores `auto` and `low` as real variants so old records deserialize
and round-trip without being rewritten as `high`, while product paths
can continue to default to `high` and avoid emitting `auto` for new
behavior.
## What changed
- Restored `ImageDetail::Auto` and `ImageDetail::Low` as first-class
protocol values.
- Preserved `auto`/`low` through rollout deserialization, MCP image
metadata, code-mode image output, and schema/type generation.
- Kept local image byte handling conservative: only `original` switches
to original-resolution loading; `auto`/`low`/`high` continue through the
resize-to-fit path while retaining their detail value.
- Added regression coverage for enum round-tripping and code-mode `low`
detail handling.
## Testing
- `just write-app-server-schema`
- `just test -p codex-protocol`
- `just test -p codex-tools`
- `just test -p codex-code-mode`
- `just test -p codex-app-server-protocol`
- `just test -p codex-core
suite::rmcp_client::stdio_image_responses_preserve_original_detail_metadata`
- `just test -p codex-core
suite::code_mode::code_mode_can_use_mcp_image_result_with_image_helper`
- Loaded broken rollouts on local fixed builds, and started/completed
new turns.
I also attempted `just test -p codex-core`; the local broad run did not
finish green: 2559 tests run, 2467 passed, 55 flaky, 91 failed, 1 timed
out. The failures were broad timeout/deadline failures across unrelated
areas; targeted changed-path core tests above passed.
## Summary
- Add optional image detail to user image inputs across core, app-server
v2, thread history/event mapping, and the generated app-server
schemas/types.
- Preserve requested detail when serializing Responses image inputs:
omitted detail stays on the existing `high` default, while explicit
`original` keeps local images on the original-resolution path.
- Support `high`/`original` consistently for tool image outputs,
including MCP `codex/imageDetail`, code-mode image helpers, and
`view_image`.
## Summary
- honor `_meta["codex/imageDetail"] == "original"` on MCP image content
and map it to `detail: "original"` where supported
- strip that detail back out when the active model does not support
original-detail image inputs
- update code-mode `image(...)` to accept individual MCP image blocks
- teach `js_repl` / `codex.emitImage(...)` to preserve the same hint
from raw MCP image outputs
- document the new `_meta` contract and add generic RMCP-backed coverage
across protocol, core, code-mode, and js_repl paths
## Summary
This PR removes `image_detail_original` as a runtime experiment and
makes original image detail available whenever the selected model
supports it.
Concretely, this change:
- drops the `image_detail_original` feature flag from the feature
registry and generated config schema
- makes tool-emitted image detail depend only on
`ModelInfo.supports_image_detail_original`
- updates `view_image` and `code_mode`/`js_repl` image emission to use
that capability check directly
- removes now-redundant experiment-specific tests and instruction
coverage
- keeps backward compatibility for existing configs by silently ignoring
a stale `features.image_detail_original` entry
The net effect is that `detail: "original"` is always available on
supported models, without requiring an experiment toggle.
## Why
`codex-core` already owns too much of the tool stack, and `AGENTS.md`
explicitly pushes us to move shared code out of `codex-core` instead of
letting it keep growing. This PR takes the next incremental step in
moving `core/src/tools` toward `codex-rs/tools` by extracting
low-coupling tool configuration and image-detail gating logic into
`codex-tools`.
That gives later extraction work a cleaner boundary to build on without
trying to move the entire tools subtree in one shot.
## What changed
- moved `ToolsConfig`, `ToolsConfigParams`, shell backend config, and
unified-exec session selection from `core/src/tools/spec.rs` into
`codex-tools`
- moved original image-detail gating and normalization into
`codex-tools`
- updated `codex-core` to consume the new `codex-tools` exports and pass
a rendered agent-type description instead of raw role config
- kept `codex-rs/tools/src/lib.rs` exports-only, with extracted unit
tests living in sibling `*_tests.rs` modules
## Testing
- `cargo test -p codex-tools`
- `cargo test -p codex-core --lib tools::spec::`