Fix: Correct limit_mm_per_prompt parameter format for vLLM #1075
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The vLLM --limit-mm-per-prompt argument uses type=json.loads for
parsing, which requires valid JSON string format. Original config
used incorrect format causing JSON parse error.
Changes:
- Fixed format in 6 serve configuration files
- Changed from: limit_mm_per_prompt: image=X
- Changed to: limit_mm_per_prompt: '{image: X}'
Tested with vLLM 0.13.0, service starts successfully.
tengqm
approved these changes
Jan 21, 2026
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PR Category
Serve
PR Types
Bug Fixes
PR Description
The --limit-mm-per-prompt argument in vLLM uses json.loads for parsing, which requires a valid JSON string format. The original configuration files used an invalid format (image=X), causing a JSON parse error during service startup.
This PR fixes the issue by updating the format to valid JSON string syntax in 6 serve configuration files:
Before: limit_mm_per_prompt: image=X
After: limit_mm_per_prompt: '{image: X}'
✅ Verified with vLLM v0.13.0 — the service now starts successfully without parsing errors.