openai/codex · error · anyhow::Error

non-spawn interaction edge {} carried a spawn fallback targe

Error message

non-spawn interaction edge {} carried a spawn fallback target

What it means

Error "non-spawn interaction edge {} carried a spawn fallback target" thrown in openai/codex.

Source

Thrown at codex-rs/rollout-trace/src/reducer/tool/agents.rs:600

                &mut existing.carried_raw_payload_ids,
                pending.carried_raw_payload_ids,
            );
            return Ok(());
        }

        self.pending_agent_interaction_edges.push(pending);
        Ok(())
    }

    /// Materializes unresolved spawn edges that have a valid child-thread fallback target.
    pub(in crate::reducer) fn resolve_pending_spawn_edge_fallbacks(&mut self) -> Result<()> {
        let pending_edges = std::mem::take(&mut self.pending_agent_interaction_edges);
        for pending in pending_edges {
            let Some(child_thread_id) = pending.unresolved_spawn_thread_id else {
                continue;
            };
            if pending.kind != InteractionEdgeKind::SpawnAgent {
                bail!(
                    "non-spawn interaction edge {} carried a spawn fallback target",
                    pending.edge_id
                );
            }
            if !self.rollout.threads.contains_key(&child_thread_id) {
                continue;
            }

            // Spawn normally resolves to the child task message because that is
            // where the delegated work first becomes model-visible. A child can
            // fail before that transcript item exists, but the spawned thread is
            // still real and the spawning tool still created it. Preserve that
            // relationship with the thread fallback instead of dropping the edge.
            self.upsert_interaction_edge(InteractionEdge {
                edge_id: pending.edge_id,
                kind: pending.kind,
                source: pending.source,
                target: TraceAnchor::Thread {

View on GitHub (pinned to 339751715c)

When it happens

Trigger: Thrown at codex-rs/rollout-trace/src/reducer/tool/agents.rs:600 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/7b6f437e40cd23b7. Report an issue: GitHub.