Amazon Q Language Server: Circular JSON serialization error in chat tabs #8312
Description
Problem
I am experiencing phantom chat windows that are not fixed by clearing the extension cache in VSCode. I have caught and identified that there is a uncaught exception being thrown in the Amazon Q Logs, pasted below. Error occurs during startup, when switching tabs, and when trying to close the phantoms.
Steps to reproduce the issue
Portion of Amazon Q Logs output
2025-11-18 22:02:30.274 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.267Z] lserver: Current history total size: 1536407 Bytes, max allowed: 209715200 Bytes
2025-11-18 22:02:30.274 [info] Entering postflare logic
2025-11-18 22:02:30.274 [info] amazonqLsp: [startup] Initializing language server configuration
2025-11-18 22:02:30.335 [info] [2025-11-18T21:02:30.329Z] lserver: Workspace context server opt-in flag is: true
2025-11-18 22:02:30.335 [info] [2025-11-18T21:02:30.330Z] lserver: Read configuration customizationArn=undefined
2025-11-18 22:02:30.335 [info] [2025-11-18T21:02:30.330Z] lserver: Read configuration optOutTelemetryPreference=OPTOUT
2025-11-18 22:02:30.336 [info] [2025-11-18T21:02:30.330Z] lserver: Read configuration customizationArn=undefined
2025-11-18 22:02:30.336 [info] [2025-11-18T21:02:30.330Z] lserver: Read configuration optOutTelemetryPreference=OPTOUT
2025-11-18 22:02:30.338 [info] amazonqLsp: [startup] Language server configuration completed successfully
2025-11-18 22:02:30.338 [info] [2025-11-18T21:02:30.335Z] lserver: Read сonfiguration includeSuggestionsWithCodeReferences=false
2025-11-18 22:02:30.338 [info] [2025-11-18T21:02:30.335Z] lserver: Read configuration shareCodeWhispererContentWithAWS=true
2025-11-18 22:02:30.343 [info] [2025-11-18T21:02:30.337Z] lserver: Read сonfiguration includeSuggestionsWithCodeReferences=false
2025-11-18 22:02:30.343 [info] [2025-11-18T21:02:30.337Z] lserver: Read configuration shareCodeWhispererContentWithAWS=true
2025-11-18 22:02:30.343 [info] [2025-11-18T21:02:30.337Z] lserver: Chat configuration updated customizationArn to undefined
2025-11-18 22:02:30.344 [info] [2025-11-18T21:02:30.337Z] lserver: Chat configuration telemetry preference to OPTOUT
2025-11-18 22:02:30.345 [info] [2025-11-18T21:02:30.337Z] lserver: Updating configuration of local context server
2025-11-18 22:02:30.346 [info] [2025-11-18T21:02:30.337Z] lserver: Setting project context indexing enabled to true
2025-11-18 22:02:30.346 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.337Z] lserver: Vector library initializing with GPU acceleration: false, index worker thread count: 0
2025-11-18 22:02:30.409 [info] initialized 'submitFeedback' command with default feedback id: Amazon Q
2025-11-18 22:02:30.413 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.405Z] lserver: Logging level changed to info
2025-11-18 22:02:30.419 [info] auth: Connection is valid: d13b9e84-b6ed-40bc-919f-389bc5b10dcf
2025-11-18 22:02:30.419 [info] auth: Updating connection state of d13b9e84-b6ed-40bc-919f-389bc5b10dcf to valid
2025-11-18 22:02:30.430 [info] using amazonqLsp service configuration: default
2025-11-18 22:02:30.448 [info] using codewhispererService service configuration: default
2025-11-18 22:02:30.485 [info] auth: Connection is valid: d13b9e84-b6ed-40bc-919f-389bc5b10dcf
2025-11-18 22:02:30.486 [info] auth: Updating connection state of d13b9e84-b6ed-40bc-919f-389bc5b10dcf to valid
2025-11-18 22:02:30.546 [info] auth: Connection is valid: d13b9e84-b6ed-40bc-919f-389bc5b10dcf
2025-11-18 22:02:30.546 [info] auth: Updating connection state of d13b9e84-b6ed-40bc-919f-389bc5b10dcf to valid
2025-11-18 22:02:30.736 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.734Z] lserver: Processing 1 workspace folders...
2025-11-18 22:02:30.736 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.734Z] lserver: Local context server has been initialized
2025-11-18 22:02:30.828 [info] AB Testing Cohort Assignments []
2025-11-18 22:02:30.829 [info] auth: Connection is valid: d13b9e84-b6ed-40bc-919f-389bc5b10dcf
2025-11-18 22:02:30.829 [info] auth: Updating connection state of d13b9e84-b6ed-40bc-919f-389bc5b10dcf to valid
2025-11-18 22:02:30.926 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"telemetry/event","params":{"name":"enterFocus"}} from chat
2025-11-18 22:02:30.927 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"ui-is-ready"} from chat
2025-11-18 22:02:30.928 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"aws/chat/ready"} from chat
2025-11-18 22:02:30.928 [info] [Info - 10:02:30 PM] [VSCode Client] "aws/chat/ready" event is received, sending chat options
2025-11-18 22:02:30.928 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"aws/chat/tabAdd","params":{"tabId":"4dgd6a"}} from chat
2025-11-18 22:02:30.928 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"telemetry/event","params":{"triggerType":"click","tabId":"4dgd6a","name":"tabAdd"}} from chat
2025-11-18 22:02:30.928 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"aws/chat/listAvailableModels","params":{"tabId":"4dgd6a"}} from chat
2025-11-18 22:02:30.933 [info] [Info - 10:02:30 PM] [VSCode Client] Chat options flags: mcpServers=true, history=true, export=true, quickActions=[/help, /clear, /compact]
2025-11-18 22:02:30.976 [info] [Info - 10:02:30 PM] [VSCode Telemetry] Emitting amazonq_enterFocusChat telemetry: {"credentialStartUrl":"https://view.awsapps.com/start","result":"Succeeded"}
2025-11-18 22:02:30.978 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.977Z] lserver: Migrated agent config to CLI format: C:\Users\Ian.aws\amazonq\agents\default.json
2025-11-18 22:02:30.979 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.977Z] lserver: MCP manager: initialized with 2 configs
2025-11-18 22:02:30.979 [info] [Warn - 10:02:30 PM] [2025-11-18T21:02:30.977Z] lserver: Agent config not found at e:\NASRDataApp.amazonq\agents\default.json, skipping.
2025-11-18 22:02:30.979 [info] [Warn - 10:02:30 PM] [2025-11-18T21:02:30.978Z] lserver: MCP config not found at e:\NASRDataApp.amazonq\mcp.json, skipping.
2025-11-18 22:02:30.979 [info] [Warn - 10:02:30 PM] [2025-11-18T21:02:30.978Z] lserver: MCP config not found at C:\Users\Ian.aws\amazonq\mcp.json, skipping.
2025-11-18 22:02:30.979 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.978Z] lserver: Loaded 0 servers from legacy MCP configs
2025-11-18 22:02:30.979 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.978Z] lserver: Successfully processed 2 agent config files and legacy MCP configs
2025-11-18 22:02:30.979 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.978Z] lserver: Using agent configuration
2025-11-18 22:02:30.979 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.978Z] lserver: MCP: discovered 0 tools across all servers
2025-11-18 22:02:30.980 [info] [Info - 10:02:30 PM] [VSCode Telemetry] Emitting amazonq_mcpConfig telemetry: {"credentialStartUrl":"https://view.awsapps.com/start","languageServerVersion":"1.45.0","numActiveServers":0,"numGlobalServers":0,"numProjectServers":0,"numToolsAlwaysAllowed":0,"numToolsDenied":0}
2025-11-18 22:02:30.980 [info] [Info - 10:02:30 PM] [2025-11-18T21:02:30.978Z] lserver: ProfileStatusMonitor started - checking MCP configuration every 24 hours
2025-11-18 22:02:30.983 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"aws/chat/tabAdd","params":{"tabId":"xj4yju","restoredTab":true}} from chat
2025-11-18 22:02:30.983 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"telemetry/event","params":{"triggerType":"click","tabId":"xj4yju","name":"tabAdd"}} from chat
2025-11-18 22:02:30.983 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"command":"aws/chat/listAvailableModels","params":{"tabId":"xj4yju"}} from chat
2025-11-18 22:02:30.990 [info] [Info - 10:02:30 PM] [VSCode Client] Received {"requestId":"8a5a1f6c-72f0-4ae6-9fcf-db27e368010c","command":"aws/chat/openTab","params":{"success":true,"result":{"tabId":"xj4yju"}}} from chat
2025-11-18 22:02:31.003 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/tabAdd","params":{"tabId":"wnijic","restoredTab":true}} from chat
2025-11-18 22:02:31.004 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"telemetry/event","params":{"triggerType":"click","tabId":"wnijic","name":"tabAdd"}} from chat
2025-11-18 22:02:31.004 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/listAvailableModels","params":{"tabId":"wnijic"}} from chat
2025-11-18 22:02:31.004 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"requestId":"2dca2f6d-f49d-4b35-a1fe-0e5931a0629d","command":"aws/chat/openTab","params":{"success":true,"result":{"tabId":"wnijic"}}} from chat
2025-11-18 22:02:31.026 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/tabAdd","params":{"tabId":"7ahnmk","restoredTab":true}} from chat
2025-11-18 22:02:31.027 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"telemetry/event","params":{"triggerType":"click","tabId":"7ahnmk","name":"tabAdd"}} from chat
2025-11-18 22:02:31.027 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/listAvailableModels","params":{"tabId":"7ahnmk"}} from chat
2025-11-18 22:02:31.064 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"requestId":"05436ac2-64fb-4d41-a639-aa722c1e7896","command":"aws/chat/openTab","params":{"success":true,"result":{"tabId":"7ahnmk"}}} from chat
2025-11-18 22:02:31.131 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/tabAdd","params":{"tabId":"6dc4ah","restoredTab":true}} from chat
2025-11-18 22:02:31.131 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"telemetry/event","params":{"triggerType":"click","tabId":"6dc4ah","name":"tabAdd"}} from chat
2025-11-18 22:02:31.131 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/listAvailableModels","params":{"tabId":"6dc4ah"}} from chat
2025-11-18 22:02:31.178 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"requestId":"56442949-835b-4bfa-9299-5fd5b15e626b","command":"aws/chat/openTab","params":{"success":true,"result":{"tabId":"6dc4ah"}}} from chat
2025-11-18 22:02:31.293 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/tabAdd","params":{"tabId":"v1s4q6","restoredTab":true}} from chat
2025-11-18 22:02:31.294 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"telemetry/event","params":{"triggerType":"click","tabId":"v1s4q6","name":"tabAdd"}} from chat
2025-11-18 22:02:31.294 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/listAvailableModels","params":{"tabId":"v1s4q6"}} from chat
2025-11-18 22:02:31.305 [info] [Info - 10:02:31 PM] [2025-11-18T21:02:31.303Z] lserver: MCP config file changed: C:\Users\Ian.aws\amazonq\agents\default.json
2025-11-18 22:02:31.305 [info] [Info - 10:02:31 PM] [2025-11-18T21:02:31.303Z] lserver: File watcher triggered - isProgrammaticChange: false, lastProgrammaticState: false
2025-11-18 22:02:31.312 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"requestId":"a2e4a410-c377-4ae2-aedd-bd0de818a16f","command":"aws/chat/openTab","params":{"success":true,"result":{"tabId":"v1s4q6"}}} from chat
2025-11-18 22:02:31.376 [info] Uncaught exception: TypeError: Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle
at JSON.stringify ()
at C:\Users\Ian\AppData\Local\aws\toolkits\language-servers\AmazonQ\1.45.0\servers\aws-lsp-codewhisperer.js:2:1843624
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
Exception origin: unhandledRejection
2025-11-18 22:02:31.376 [info] Uncaught exception: TypeError: Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle
at JSON.stringify ()
at C:\Users\Ian\AppData\Local\aws\toolkits\language-servers\AmazonQ\1.45.0\servers\aws-lsp-codewhisperer.js:2:1843624
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
Exception origin: unhandledRejection
2025-11-18 22:02:31.376 [info] Uncaught exception: TypeError: Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle
at JSON.stringify ()
at C:\Users\Ian\AppData\Local\aws\toolkits\language-servers\AmazonQ\1.45.0\servers\aws-lsp-codewhisperer.js:2:1843624
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
Exception origin: unhandledRejection
2025-11-18 22:02:31.376 [info] Uncaught exception: TypeError: Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle
at JSON.stringify ()
at C:\Users\Ian\AppData\Local\aws\toolkits\language-servers\AmazonQ\1.45.0\servers\aws-lsp-codewhisperer.js:2:1843624
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
Exception origin: unhandledRejection
Uncaught exception: TypeError: Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle
at JSON.stringify ()
at C:\Users\Ian\AppData\Local\aws\toolkits\language-servers\AmazonQ\1.45.0\servers\aws-lsp-codewhisperer.js:2:1843624
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
Exception origin: unhandledRejection
Uncaught exception: TypeError: Converting circular structure to JSON
--> starting at object with constructor 'TLSSocket'
| property 'parser' -> object with constructor 'HTTPParser'
--- property 'socket' closes the circle
at JSON.stringify ()
at C:\Users\Ian\AppData\Local\aws\toolkits\language-servers\AmazonQ\1.45.0\servers\aws-lsp-codewhisperer.js:2:1843624
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
Exception origin: unhandledRejection
2025-11-18 22:02:31.377 [info] [Info - 10:02:31 PM] [VSCode Telemetry] Emitting runtime_processCrash telemetry: {"reasonDesc":"TypeError: Converting circular structure to JSON --> starting at object with constructor 'TLSSocket' | property 'parser' -> object with constructor 'HTTPParser' --- property 'socket' closes the circle"}
2025-11-18 22:02:31.377 [info] [Info - 10:02:31 PM] [VSCode Telemetry] Emitting runtime_processCrash telemetry: {"reasonDesc":"TypeError: Converting circular structure to JSON --> starting at object with constructor 'TLSSocket' | property 'parser' -> object with constructor 'HTTPParser' --- property 'socket' closes the circle"}
2025-11-18 22:02:31.377 [info] [Info - 10:02:31 PM] [VSCode Telemetry] Emitting runtime_processCrash telemetry: {"reasonDesc":"TypeError: Converting circular structure to JSON --> starting at object with constructor 'TLSSocket' | property 'parser' -> object with constructor 'HTTPParser' --- property 'socket' closes the circle"}
2025-11-18 22:02:31.377 [info] [Info - 10:02:31 PM] [VSCode Telemetry] Emitting runtime_processCrash telemetry: {"reasonDesc":"TypeError: Converting circular structure to JSON --> starting at object with constructor 'TLSSocket' | property 'parser' -> object with constructor 'HTTPParser' --- property 'socket' closes the circle"}
2025-11-18 22:02:31.377 [info] [Info - 10:02:31 PM] [VSCode Telemetry] Emitting runtime_processCrash telemetry: {"reasonDesc":"TypeError: Converting circular structure to JSON --> starting at object with constructor 'TLSSocket' | property 'parser' -> object with constructor 'HTTPParser' --- property 'socket' closes the circle"}
2025-11-18 22:02:31.377 [info] [Info - 10:02:31 PM] [VSCode Telemetry] Emitting runtime_processCrash telemetry: {"reasonDesc":"TypeError: Converting circular structure to JSON --> starting at object with constructor 'TLSSocket' | property 'parser' -> object with constructor 'HTTPParser' --- property 'socket' closes the circle"}
2025-11-18 22:02:31.378 [info] [Info - 10:02:31 PM] [2025-11-18T21:02:31.376Z] lserver: abconfig: []
2025-11-18 22:02:31.412 [info] [Info - 10:02:31 PM] [VSCode Client] Received {"command":"aws/chat/tabAdd","params":{"tabId":"b6vtfu","restoredTab":true}} from chat
System details (run AWS: About and/or Amazon Q: About)
Amazon Q Language Server version: 1.45.0
Error: "Converting circular structure to JSON" with TLSSocket
Impact: Phantom chat tabs, corrupted chat state
Reproduction: Occurs during chat tab restoration on VS Code startup
Log location: Line 1843624 in aws-lsp-codewhisperer.js