Error when i use deepseek-v4-flash

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1

Request ID: cf87522c-4f2a-4ea8-a65f-89b1835e8b9d
{“error”:“ERROR_PROVIDER_ERROR”,“details”:{“title”:“Provider Error”,“detail”:“Provider returned error: {“error”:{“message”:“The reasoning_content in the thinking mode must be passed back to the API.”,“type”:“invalid_request_error”,“param”:null,“code”:“invalid_request_error”}}”,“isRetryable”:false,“additionalInfo”:{},“buttons”:,“planChoices”:},“isExpected”:true}
Provider Error Provider returned error: {“error”:{“message”:“The reasoning_content in the thinking mode must be passed back to the API.”,“type”:“invalid_request_error”,“param”:null,“code”:“invalid_request_error”}}
Cvs: Provider Error Provider returned error: {“error”:{“message”:“The reasoning_content in the thinking mode must be passed back to the API.”,“type”:“invalid_request_error”,“param”:null,“code”:“invalid_request_error”}}
at Pf_ (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:29432:24260)
at Rf_ (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:29432:23144)
at Uf_ (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:29433:6490)
at q0h.run (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:29433:11307)
at async cQi.runAgentLoop (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:41748:12418)
at async Vnm.streamFromAgentBackend (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:41816:12344)
at async Vnm.getAgentStreamResponse (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:41816:19567)
at async lCt.submitChatMaybeAbortCurrent (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:29548:16906)
at async Object.Va [as onSubmit] (vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:40804:4230)
at async vscode-file://vscode-app/o:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:40803:100980

2

Hi there!

We detected that this may be a bug report, so we’ve moved your post to the Bug Reports category.

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5

You may try this workaround: GitHub - yxlao/deepseek-cursor-proxy: Fixes reasoning_content issue of DeepSeek V4, supprting deepseek-v4-pro and deepseek-v4-flash · GitHub

This proxy injects the missing `reasoning_content` for deepseek requests.

7

Hey, this is a known issue with BYOK and DeepSeek V4 in thinking mode: our proxy isn’t passing reasoning_content back in multi-turn requests with tool calls, and the DeepSeek API rejects them with invalid_request_error. I reported the issue internally, no ETA for a fix yet.

A workaround was already shared earlier in this thread: the proxy by @yxlao that reinjects reasoning_content: GitHub - yxlao/deepseek-cursor-proxy: Fixes reasoning_content issue of DeepSeek V4, supprting deepseek-v4-pro and deepseek-v4-flash · GitHub

Main discussion and extra context: Compatibility with DeepSeek model's design to return reasoning content after tool calls?