## 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.
**Disabling Image-Gen for Non-SIWC Codex Users**
We are only enabling image-gen feature for SIWC Codex users until there
comes a fix in ResponsesAPI to omit output from responses.completed, to
prevent the following issues:
1. websocket blows up due to heavier load (images) than before (text)
2. http parser streams through n^2 of n-base64 bytes (sum of base64s of
all images generated in turn) that causes long delays in
turn_completion.
Allow multi_agent_v2 features to have its own temporary configuration
under `[features.multi_agent_v2]`
```
[features.multi_agent_v2]
enabled = true
usage_hint_enabled = false
usage_hint_text = "Custom delegation guidance."
hide_spawn_agent_metadata = true
```
Absent `usage_hint_text` means use the default hint.
```
[features]
multi_agent_v2 = true
```
still works as the boolean shorthand.
## Summary
- make `CODEX_EXEC_SERVER_URL=none` map to an explicit disabled
environment mode instead of inferring from a missing URL
- expose environment capabilities (`exec_enabled`, `filesystem_enabled`)
so tool building can gate behavior explicitly and future
multi-environment work has a clearer seam
- suppress env-backed tools when the relevant capability is unavailable,
including exec tools, `js_repl`, `apply_patch`, `list_dir`, and
`view_image`
- keep handler/runtime backstops so disabled environments still reject
execution if a tool path somehow bypasses registration
## Testing
- `just fmt`
- `cargo test -p codex-exec-server`
- `cargo test -p codex-tools
disabled_environment_omits_environment_backed_tools`
- `cargo test -p codex-tools
environment_capabilities_gate_exec_and_filesystem_tools_independently`
- remote devbox Bazel build via `codex-applied-devbox`:
`//codex-rs/cli:cli`
## 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::`
