Cline error
Cline: Model returned empty response
Model returned empty responseStatus: OpenLast verified 3 documented fixes3 sources
What it means
A turn finished without any visible model output (no text and no tool call), so Cline fails the turn.
Causes
- Act mode running with a low Max Output Tokens cap: a maintainer explained a turn can spend its whole budget before producing visible output, and Cline reports that as "Model returned empty response" (#13113).
- Before 4.1.4, empty responses were only retried on Ollama, causing hard failures on OpenRouter, Cline, and OpenAI-compatible endpoints.
- Before 4.1.22, responses blocked by a content filter were also reported as "Model returned empty response".
- Messages whose content held only empty text parts were rejected by strict providers (fixed in 4.1.9).
How to fix it
- Fix 1.
Check the Max Output Tokens setting for Act mode and whether "use different models for Plan and Act mode" is enabled (maintainer request in #13113).
- Fix 2.
Update Cline: 4.1.4 retries empty model responses on every provider; 4.1.9 fixes the empty-text-parts case; 4.1.22 shows a content-filter message suggesting rephrasing instead of the empty response error.
- Fix 3.
If it persists on the latest version, maintainers ask for the exact error row text plus View > Output > Cline logs, conversation length, and whether it happens on every mode switch.
More Cline errors
All 17 Cline errorsShell Integration Unavailable. Cline may have trouble viewing the command's output. Please update VSCode (CMD/CTRL + Shift + P → "Update") and make sure you're using a supported shell: zsh, bash, fish, or PowerShell (CMD/CTRL + Shift + P → "Terminal: Select Default Profile").Status: WorkaroundError executing command: The command ran successfully, but we couldn't capture its output. Please proceed accordingly.Status: Fixed in releaseCommand failed with exit code 1: powershell (Get-CimInstance -ClassName Win32_OperatingSystem).caption 'powershell' is not recognized as an internal or external command, operable program or batch file.Status: WorkaroundUnexpected API Response: The language model did not provide any assistant messages. This may indicate an issue with the API or the model's output.Status: WorkaroundInvalid API Response: The provider returned an empty or unparsable response. This is a provider-side issue where the model failed to generate valid output or returned tool calls that Cline cannot process. Retrying the request may help resolve this issue.Status: OpenFunction 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.Status: Fixed in release429 {"type":"error","error":{"type":"rate_limit_error","message":"Number of request tokens has exceeded your per-minute rate limit (https://docs.anthropic.com/en/api/rate-limits); see the response headers for current usage. Please reduce the prompt length or the maximum tokens requested, or try again later. You may also contact sales at https://www.anthropic.com/contact-sales to discuss your options for a rate limit increase."}}Status: WorkaroundInvalid MCP settings format. Please ensure your settings follow the correct JSON format.Status: Workaround
Related reading
- What Is Cline? The Open-Source AI Coding Agent for VS CodeCline is a free, open-source VS Code extension for agentic AI coding. Bring your own model, a cloud API or a local one via Ollama, with no vendor lock-in.
- Every AI Coding Tool Compared: The 2026 MatrixEvery AI coding tool compared: 15 terminal, IDE, cloud and browser tools side by side on pricing, model surface, strengths, weaknesses and best use cases.
FAQ
What does "Model returned empty response" mean in Cline?
A turn finished without any visible model output (no text and no tool call), so Cline fails the turn.
How do I fix "Model returned empty response"?
There are 3 documented fixes. Start with the first: Check the Max Output Tokens setting for Act mode and whether "use different models for Plan and Act mode" is enabled (maintainer request in #13113).
Is this Cline error fixed?
Status: Open. Still open upstream. Any documented fixes are workarounds so far. Affected versions: 4.x (reported on 4.1.7); partial fixes in 4.1.4, 4.1.9, 4.1.22
Sources
Last verified against 3 sources: official docs, maintainer replies and release notes.
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