Updates the configuration documentation to clarify and improve the
description of the `developer_instructions` and `instructions` fields.
Documentation updates:
* Added a description for the `developer_instructions` field in
`docs/config.md`, clarifying that it provides additional developer
instructions.
* Updated the comments in `docs/example-config.md` to specify that
`developer_instructions` is injected before `AGENTS.md`, and clarified
that the `instructions` field is ignored and that `AGENTS.md` is
preferred.
___
ref #7973
Thanks to @miraclebakelaser for the message. I have double-confirmed
that developer instructions are always injected before user
instructions. According to the source code
[codex_core::codex::Session::build_initial_context](https://github.com/openai/codex/blob/rust-v0.77.0-alpha.2/codex-rs/core/src/codex.rs#L1279),
we can see the specific order of these instructions.
### Summary
With codesigning on Mac, Windows and Linux, we should be able to safely
remove `features.rmcp_client` and `use_experimental_use_rmcp_client`
check from the codebase now.
## TUI2: Normalize Mouse Scroll Input Across Terminals (Wheel +
Trackpad)
This changes TUI2 scrolling to a stream-based model that normalizes
terminal scroll event density into consistent wheel behavior (default:
~3 transcript lines per physical wheel notch) while keeping trackpad
input higher fidelity via fractional accumulation.
Primary code: `codex-rs/tui2/src/tui/scrolling/mouse.rs`
Doc of record (model + probe-derived data):
`codex-rs/tui2/docs/scroll_input_model.md`
### Why
Terminals encode both mouse wheels and trackpads as discrete scroll
up/down events with direction but no magnitude, and they vary widely in
how many raw events they emit per physical wheel notch (commonly 1, 3,
or 9+). Timing alone doesn’t reliably distinguish wheel vs trackpad, so
cadence-based heuristics are unstable across terminals/hardware.
This PR treats scroll input as short *streams* separated by silence or
direction flips, normalizes raw event density into tick-equivalents,
coalesces redraws for dense streams, and exposes explicit config
overrides.
### What Changed
#### Scroll Model (TUI2)
- Stream detection
- Start a stream on the first scroll event.
- End a stream on an idle gap (`STREAM_GAP_MS`) or a direction flip.
- Normalization
- Convert raw events into tick-equivalents using per-terminal
`tui.scroll_events_per_tick`.
- Wheel-like vs trackpad-like behavior
- Wheel-like: fixed “classic” lines per wheel notch; flush immediately
for responsiveness.
- Trackpad-like: fractional accumulation + carry across stream
boundaries; coalesce flushes to ~60Hz to avoid floods and reduce “stop
lag / overshoot”.
- Trackpad divisor is intentionally capped: `min(scroll_events_per_tick,
3)` so terminals with dense wheel ticks (e.g. 9 events per notch) don’t
make trackpads feel artificially slow.
- Auto mode (default)
- Start conservatively as trackpad-like (avoid overshoot).
- Promote to wheel-like if the first tick-worth of events arrives
quickly.
- Fallback for 1-event-per-tick terminals (no tick-completion timing
signal).
#### Trackpad Acceleration
Some terminals produce relatively low vertical event density for
trackpad gestures, which makes large/faster swipes feel sluggish even
when small motions feel correct. To address that, trackpad-like streams
apply a bounded multiplier based on event count:
- `multiplier = clamp(1 + abs(events) / scroll_trackpad_accel_events,
1..scroll_trackpad_accel_max)`
The multiplier is applied to the trackpad stream’s computed line delta
(including carried fractional remainder). Defaults are conservative and
bounded.
#### Config Knobs (TUI2)
All keys live under `[tui]`:
- `scroll_wheel_lines`: lines per physical wheel notch (default: 3).
- `scroll_events_per_tick`: raw vertical scroll events per physical
wheel notch (terminal-specific default; fallback: 3).
- Wheel-like per-event contribution: `scroll_wheel_lines /
scroll_events_per_tick`.
- `scroll_trackpad_lines`: baseline trackpad sensitivity (default: 1).
- Trackpad-like per-event contribution: `scroll_trackpad_lines /
min(scroll_events_per_tick, 3)`.
- `scroll_trackpad_accel_events` / `scroll_trackpad_accel_max`: bounded
trackpad acceleration (defaults: 30 / 3).
- `scroll_mode = auto|wheel|trackpad`: force behavior or use the
heuristic (default: `auto`).
- `scroll_wheel_tick_detect_max_ms`: auto-mode promotion threshold (ms).
- `scroll_wheel_like_max_duration_ms`: auto-mode fallback for
1-event-per-tick terminals (ms).
- `scroll_invert`: invert scroll direction (applies to wheel +
trackpad).
Config docs: `docs/config.md` and field docs in
`codex-rs/core/src/config/types.rs`.
#### App Integration
- The app schedules follow-up ticks to close idle streams (via
`ScrollUpdate::next_tick_in` and `schedule_frame_in`) and finalizes
streams on draw ticks.
- `codex-rs/tui2/src/app.rs`
#### Docs
- Single doc of record describing the model + preserved probe
findings/spec:
- `codex-rs/tui2/docs/scroll_input_model.md`
#### Other (jj-only friendliness)
- `codex-rs/tui2/src/diff_render.rs`: prefer stable cwd-relative paths
when the file is under the cwd even if there’s no `.git`.
### Terminal Defaults
Per-terminal defaults are derived from scroll-probe logs (see doc).
Notable:
- Ghostty currently defaults to `scroll_events_per_tick = 3` even though
logs measured ~9 in one setup. This is a deliberate stopgap; if your
Ghostty build emits ~9 events per wheel notch, set:
```toml
[tui]
scroll_events_per_tick = 9
```
### Testing
- `just fmt`
- `just fix -p codex-core --allow-no-vcs`
- `cargo test -p codex-core --lib` (pass)
- `cargo test -p codex-tui2` (scroll tests pass; remaining failures are
known flaky VT100 color tests in `insert_history`)
### Review Focus
- Stream finalization + frame scheduling in `codex-rs/tui2/src/app.rs`.
- Auto-mode promotion thresholds and the 1-event-per-tick fallback
behavior.
- Trackpad divisor cap (`min(events_per_tick, 3)`) and acceleration
defaults.
- Ghostty default tradeoff (3 vs ~9) and whether we should change it.
# External (non-OpenAI) Pull Request Requirements
Before opening this Pull Request, please read the dedicated
"Contributing" markdown file or your PR may be closed:
https://github.com/openai/codex/blob/main/docs/contributing.md
If your PR conforms to our contribution guidelines, replace this text
with a detailed and high quality description of your changes.
Include a link to a bug report or enhancement request.
This pull request makes a small update to the session picker
documentation for `codex resume`. The main change clarifies how to view
the original working directory (CWD) for sessions and when the Git
branch is shown.
- The session picker now displays the recorded Git branch when
available, and instructions are added for showing the original working
directory by using the `--all` flag, which also disables CWD filtering
and adds a `CWD` column.
When PaletteMode::Ansi16, render tool cards with solid ANSI backgrounds and force high-contrast text (white on dark, black on light).
Mappings:
- Auto Drive: magenta / light magenta
- Agent (read): green / light green
- Agent (write): yellow / light yellow
- Browser: red / light red
Also extend /demo to accept 'auto drive card' for quickly previewing all ANSI-16 backgrounds.
We should not have any `PathBuf` fields in `ConfigToml` or any of the
transitive structs we include, as we should use `AbsolutePathBuf`
instead so that we do not have to keep track of the file from which
`ConfigToml` was loaded such that we need it to resolve relative paths
later when the values of `ConfigToml` are used.
I only found two instances of this: `experimental_instructions_file` and
`experimental_compact_prompt_file`. Incidentally, when these were
specified as relative paths, they were resolved against `cwd` rather
than `config.toml`'s parent, which seems wrong to me. I changed the
behavior so they are resolved against the parent folder of the
`config.toml` being parsed, which we get "for free" due to the
introduction of `AbsolutePathBufGuard ` in
https://github.com/openai/codex/pull/7796.
While it is not great to change the behavior of a released feature,
these fields are prefixed with `experimental_`, which I interpret to
mean we have the liberty to change the contract.
For reference:
- `experimental_instructions_file` was introduced in
https://github.com/openai/codex/pull/1803
- `experimental_compact_prompt_file` was introduced in
https://github.com/openai/codex/pull/5959
In preparation for in-repo configuration support, this updates
`WritableRoot::get_writable_roots_with_cwd()` to include the `.codex`
subfolder in `WritableRoot.read_only_subpaths`, if it exists, as we
already do for `.git`.
As noted, currently, like `.git`, `.codex` will only be read-only under
macOS Seatbelt, but we plan to bring support to other OSes, as well.
Updated the integration test in `seatbelt.rs` so that it actually
attempts to run the generated Seatbelt commands, verifying that:
- trying to write to `.codex/config.toml` in a writable root fails
- trying to write to `.git/hooks/pre-commit` in a writable root fails
- trying to write to the writable root containing the `.codex` and
`.git` subfolders succeeds
## Notes
Skills are behind the experimental `skills` feature flag (disabled by
default), but the skills guide didn't explain how to turn them on.
- Add an explicit enable section to `docs/skills.md` (config +
`--enable`)
- Add the skills flag to `docs/config.md` and `docs/example-config.md`
- Document the `/skills` slash command
## Changes
- Update config docs and example config comments to state that "xhigh"
is supported on gpt-5.2 as well as gpt-5.1-codex-max
- Adjust the FAQ model-support section to reflect broader xhigh
availability
We decided that `*.rules` is a more fitting (and concise) file extension
than `*.codexpolicy`, so we are changing the file extension for the
"execpolicy" effort. We are also changing the subfolder of `$CODEX_HOME`
from `policy` to `rules` to match.
This PR updates the in-repo docs and we will update the public docs once
the next CLI release goes out.
Locally, I created `~/.codex/rules/default.rules` with the following
contents:
```
prefix_rule(pattern=["gh", "pr", "view"])
```
And then I asked Codex to run:
```
gh pr view 7888 --json title,body,comments
```
and it was able to!
James Peter