dc2f26f7b5
## Problem
The `is_api_message` function in `conversation_history.rs` had a
misalignment between its documentation and implementation:
- **Comment stated**: "Anything that is not a system message or
'reasoning' message is considered an API message"
- **Code behavior**: Was returning `true` for `ResponseItem::Reasoning`,
meaning reasoning messages were incorrectly treated as API messages
This inconsistency could lead to reasoning messages being persisted in
conversation history when they should be filtered out.
## Root Cause
Investigation revealed that reasoning messages are explicitly excluded
throughout the codebase:
1. **Chat completions API** (lines 267-272 in `chat_completions.rs`)
omits reasoning from conversation history:
```rust
ResponseItem::Reasoning { .. } | ResponseItem::Other => {
// Omit these items from the conversation history.
continue;
}
```
2. **Existing tests** like `drops_reasoning_when_last_role_is_user` and
`ignores_reasoning_before_last_user` validate that reasoning should be
excluded from API payloads
## Solution
Fixed the `is_api_message` function to align with its documentation and
the rest of the codebase:
```rust
// Before: Reasoning was incorrectly returning true
ResponseItem::Reasoning { .. } | ResponseItem::WebSearchCall { .. } => true,
// After: Reasoning correctly returns false
ResponseItem::WebSearchCall { .. } => true,
ResponseItem::Reasoning { .. } | ResponseItem::Other => false,
```
## Testing
- Enhanced existing test to verify reasoning messages are properly
filtered out
- All 264 core tests pass, including 8 chat completions tests that
validate reasoning behavior
- No regressions introduced
This ensures reasoning messages are consistently excluded from API
message processing across the entire codebase.
codex-core
This crate implements the business logic for Codex. It is designed to be used by the various Codex UIs written in Rust.
Dependencies
Note that codex-core makes some assumptions about certain helper utilities being available in the environment. Currently, this support matrix is:
macOS
Expects /usr/bin/sandbox-exec to be present.
Linux
Expects the binary containing codex-core to run the equivalent of codex sandbox linux (legacy alias: codex debug landlock) when arg0 is codex-linux-sandbox. See the codex-arg0 crate for details.
All Platforms
Expects the binary containing codex-core to simulate the virtual apply_patch CLI when arg1 is --codex-run-as-apply-patch. See the codex-arg0 crate for details.