{"record":{"id":"4b35b8c10ccae946","repo":"Hmbown/CodeWhale","slug":"failed-to-sync-thread-session-e","errorCode":null,"errorMessage":"Failed to sync thread session: {e}","messagePattern":"Failed to sync thread session: (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"crates/tui/src/runtime_threads.rs","lineNumber":6806,"sourceCode":"                .map(|s| SystemPrompt::Text(s.clone()));\n            if !session_messages.is_empty() || sys_prompt.is_some() {\n                engine\n                    .send(Op::SyncSession {\n                        session_id: thread.session_id.clone(),\n                        messages: session_messages,\n                        system_prompt: sys_prompt,\n                        system_prompt_override: thread.system_prompt.is_some(),\n                        model: route_model.clone(),\n                        workspace: thread.workspace.clone(),\n                        mode: RuntimePolicyProjection::from_persisted(\n                            &thread.mode,\n                            thread.permission_posture.as_deref(),\n                            thread.auto_approve,\n                        )\n                        .mode,\n                    })\n                    .await\n                    .map_err(|e| anyhow!(\"Failed to sync thread session: {e}\"))?;\n            }\n\n            let mut active = self.active.lock().await;\n            if let Some(winner) = active\n                .engines\n                .get(&thread.id)\n                .map(|state| state.engine.clone())\n            {\n                touch_lru(&mut active.lru, &thread.id);\n                drop(active);\n                engine.cancel_with_reason(crate::core::engine::CancelReason::Internal);\n                let _ = engine.try_send(Op::Shutdown);\n                return Ok(winner);\n            }\n\n            // Atomically compare the record used for construction with the latest\n            // durable record while holding the same active -> thread lock order as\n            // updates. A concurrent workspace/model/session/policy change makes","sourceCodeStart":6788,"sourceCodeEnd":6824,"githubUrl":"https://github.com/Hmbown/CodeWhale/blob/0c42157ee52f9d55af2b506d71b46249910f77d3/crates/tui/src/runtime_threads.rs#L6788-L6824","documentation":"Wrapper raised when the engine.send(Op::SyncSession ...) call fails while (re)attaching a thread: the engine could not accept the session sync carrying session_id, prior messages, system prompt, route model, workspace, and policy projection. The inner {e} carries the engine-side cause; typically a closed op channel or an engine task that is shutting down.","triggerScenarios":"Thrown at crates/tui/src/runtime_threads.rs:6806 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Check whether the engine task for this thread already shut down; restart the session and retry the attach","Inspect the inner error for engine-side rejection causes (bad session state, closed channel)","Avoid attaching the same thread from two processes simultaneously"],"exampleFix":null,"handlingStrategy":"try-catch","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"0c42157ee52f9d55af2b506d71b46249910f77d3","analyzedAt":"2026-08-20T21:50:45.477Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-14T00:17:10.932Z"}