## Why
The skills extension needs a real turn-time path before host, executor,
or remote skills can be routed through it. The previous code was mostly
a placeholder catalog/provider sketch, so there was no bounded
available-skills fragment, no source-owned `SKILL.md` read, and no place
for warnings or per-turn selection state to live.
This PR makes `ext/skills` the authority-preserving flow for listing
candidate skills and injecting only explicitly selected main prompts,
without adding more of that logic to `codex-core`.
## What changed
- Expands catalog entries with `main_prompt`, display path, short
description, dependency metadata, enabled/prompt visibility flags, and
authority/package-aware read requests.
- Replaces the placeholder `providers/*` modules with
`SkillProviderSource` and `SkillProviders`, routing list/read/search
calls by source kind and surfacing provider failures as warnings.
- Adds bounded available-skills rendering and `SKILL.md` main-prompt
truncation before the fragments enter model context.
- Resolves explicit skill selections from structured `UserInput::Skill`,
skill-file mentions, `skill://...` paths, and plain `$skill` text
mentions, then reads selected prompts through their owning provider.
- Stores mutable per-thread skills config and per-turn
catalog/selection/warning state.
- Adds `install_with_providers` so tests and future host wiring can
supply concrete providers.
## Testing
- Not run locally.
- Added `codex-rs/ext/skills/tests/skills_extension.rs` coverage for
available-catalog injection, selected prompt injection through the
owning provider, and prompt-hidden skills that remain invokable.
## Why
The skills extension needs the resolved turn environments to build a
real per-turn `SkillListQuery`. The previous `TurnLifecycleContributor`
hook only had a turn id, so it could only seed a placeholder query and
never carry the executor authorities that executor-scoped skill routing
will need.
Moving catalog resolution onto `TurnInputContributor` puts the skills
extension on the same turn-preparation path that already has the
environment ids and working directories for the submitted turn, while
keeping the actual prompt injection work for follow-up changes.
## What changed
- switch `ext/skills` from `TurnLifecycleContributor` to
`TurnInputContributor`
- build `executor_authorities` from `TurnInputContext.environments` and
pass them through `SkillListQuery`
- keep storing the resolved catalog in `SkillsTurnState`, but drop the
placeholder query helper that no longer matches the real data flow
- update the extension TODOs to reflect that per-turn catalog resolution
now happens in the turn-input contributor, and that prompt/context
injection still needs to move later
## Testing
- Not run locally.
## Disclaimer
This is only here for iteration purpose! Do not make any code rely on
this
## Why
Skills still live behind `codex-core` discovery and injection paths, but
the extension system needs an authority-aware home before that logic can
move. This adds that boundary without changing current skills behavior,
and keeps host, executor, and remote skills distinct so future
list/read/search flows do not collapse back to ambient local paths.
## What changed
- Add the `codex-skills-extension` workspace/Bazel crate under
`ext/skills`.
- Define the initial catalog, authority, provider, and turn-state types
for authority-bound skill packages and resources.
- Register placeholder thread/config/prompt/turn lifecycle contributors
plus host, executor, and remote provider aggregation points.
- Capture the remaining extraction work as TODOs, including the missing
extension API hooks needed for per-turn catalog construction and typed
skill injection.
- Keep plugins outside the runtime skills model: plugin-installed skills
are treated as materialized host-owned skill sources once available.
## Verification
- Not run locally.
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