Where does the bug appear (feature/product)?
Cursor IDE
Describe the Bug
Provider returned error: [{ “error”: { “code”: 400, “message”: “Function call is missing a thought_signature in functionCall parts. This is required for tools to work correctly, and missing thought_signature may lead to degraded model performance. Additional data, function call default_api:StrReplace , position 111. Please refer to … for more details.”, “status”: “INVALID_ARGUMENT” } } ]
Steps to Reproduce
add api key add 3.1 flash
Expected Behavior
it should work
Operating System
MacOS
Version Information
cursor ide
For AI issues: which model did you use?
gemini-3.1-flash-lite-preview
For AI issues: add Request ID with privacy disabled
Request ID: 5a1bbd17-8854-4d20-9b13-3e867a1e6d43
{“error”:“ERROR_PROVIDER_ERROR”,“details”:{“title”:“Provider Error”,“detail”:“Provider returned error: [{\n "error": {\n "code": 400,\n "message": "Function call is missing a thought_signature in functionCall parts. This is required for tools to work correctly, and missing thought_signature may lead to degraded model performance. Additional data, function call default_api:StrReplace , position 111. Please refer to https://ai.google.dev/gemini-api/docs/thought-signatures for more details.",\n "status": "INVALID_ARGUMENT"\n }\n}\n]”,“isRetryable”:false,“additionalInfo”:{},“buttons”:,“planChoices”:},“isExpected”:true}
Provider Error Provider returned error: [{
“error”: {
“code”: 400,
“message”: “Function call is missing a thought_signature in functionCall parts. This is required for tools to work correctly, and missing thought_signature may lead to degraded model performance. Additional data, function call default_api:StrReplace , position 111. Please refer to https://ai.google.dev/gemini-api/docs/thought-signatures for more details.”,
“status”: “INVALID_ARGUMENT”
}
}
]
TAi: Provider Error Provider returned error: [{
“error”: {
“code”: 400,
“message”: “Function call is missing a thought_signature in functionCall parts. This is required for tools to work correctly, and missing thought_signature may lead to degraded model performance. Additional data, function call default_api:StrReplace , position 111. Please refer to … for more details.”,
“status”: “INVALID_ARGUMENT”
}
}
]
at n5A (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:34249:23670)
at e5A (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:34249:22658)
at l5A (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:34250:6285)
at _ou.run (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:34250:10400)
at async vOa.runAgentLoop (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:46813:9906)
at async I3u.streamFromAgentBackend (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:46867:9277)
at async I3u.getAgentStreamResponse (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:46867:13639)
at async bMe.submitChatMaybeAbortCurrent (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:34310:17597)
at async nc (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:45792:4828)
Does this stop you from using Cursor
Yes - Cursor is unusable