tool call start used thread {thread_id}, but Codex turn {cod

Error message

tool call start used thread {thread_id}, but Codex turn {codex_turn_id} belongs to {}

What it means

Error "tool call start used thread {thread_id}, but Codex turn {codex_turn_id} belongs to {}" thrown in openai/codex.

Source

Thrown at codex-rs/rollout-trace/src/reducer/tool.rs:401

        self.rollout
            .codex_turns
            .get(codex_turn_id)
            .map(|turn| turn.thread_id.clone())
            .with_context(|| {
                format!("tool call start referenced unknown Codex turn {codex_turn_id}")
            })
    }

    fn validate_tool_turn(&self, thread_id: &str, codex_turn_id: Option<&str>) -> Result<()> {
        if !self.rollout.threads.contains_key(thread_id) {
            bail!("tool call start referenced unknown thread {thread_id}");
        }
        if let Some(codex_turn_id) = codex_turn_id {
            let Some(turn) = self.rollout.codex_turns.get(codex_turn_id) else {
                bail!("tool call start referenced unknown Codex turn {codex_turn_id}");
            };
            if turn.thread_id != thread_id {
                bail!(
                    "tool call start used thread {thread_id}, but Codex turn {codex_turn_id} \
                     belongs to {}",
                    turn.thread_id
                );
            }
        }
        Ok(())
    }

    fn ensure_unique_model_visible_tool_call(
        &self,
        model_visible_call_id: Option<&str>,
        tool_call_id: &str,
    ) -> Result<()> {
        let Some(model_visible_call_id) = model_visible_call_id else {
            return Ok(());
        };
        if let Some(existing) = self.single_tool_for_model_visible_call(model_visible_call_id)?

View on GitHub (pinned to 339751715c)

When it happens

Trigger: Thrown at codex-rs/rollout-trace/src/reducer/tool.rs:401 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of openai/codex@339751715c (2026-08-25). Data as JSON: /api/errors/37608618387ccc50. Report an issue: GitHub.