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Problems.

Models fail to return valid structured output

LLM apps8 posts from 8 people6d active+22 posts in the last 7 days, 2 the 7 days before (steady)

Posts per day

Posts per day8 posts, Aug 31 to Sep 25

The posts behind it

8, newest first
PostDate
JEV almost dead: CLM vs JEV...performance on Terminal-Bench 2.1 (87.6%) and DeepSWE (81.6%) , whereas zero-shot Jev struggled on those exact benchmarks (scoring ~71% on DeepSWE).. 3. Where Jev Still Has the Edge (CLM-8B Limitations) While CLM covers the entire feature surface of Jev, the current CLM-v0.1-8B...r/LocalLLaMAu/R_DuncanSep 24yesterday
...outputs to gpt-5-mini made zero sense just because 5 was reasoning model and there was no way to disable the reasoning and it also did not have support for fine-tuning. So essentially I was not able to get nowhere close to the accuracy of previous model and it was slower, and...Hacker News commentsbuckwheatmilkSep 232 days ago
Feature Request: Fast Tool Gating & Single-Pass Selection via Prefill Logit Slicing### Prerequisites - [x] I am running the latest code. Mention the version if possible as well. - [x] I carefully followed the [README.md](https://github.com/ggml-org/llama.cpp/blob/master/README.md). - [x] I searched using keywords relevant to my issue to make sure that I am...ggml-org/llama.cppmattepiuSep 178 days ago
[Bug]: DashScope FunctionTool conversion drops nested JSON Schema definitions## Bug description `llama-index-llms-dashscope==0.7.0` corrupts valid nested JSON Schema when it converts a `FunctionTool` for DashScope. `DashScope._convert_tool_to_dashscope_format()` retains only `type` and `properties` from `tool.metadata.get_parameters_dict()`. For Pydantic...run-llama/llama_indexGYWang1983Sep 178 days ago
Ollama: think=False is coerced to None (falls back to self.thinking) in chat/stream_chat/achat/astream_chat...4) gets the instance default instead - the opposite of what was asked - and there is no way to disable thinking per call when `self.thinking` is truthy or `None` (Ollama then decides for itself). Expected: The fix is four lines, one per method. With it the request body carries...run-llama/llama_indexrich12312Sep 62 weeks ago
`HumanInTheLoopMiddleware` silently drops configured `args_schema` from interrupt payload### Submission checklist - [x] This is a bug, not a usage question. - [x] I added a clear and descriptive title that summarizes this issue. - [x] I used the GitHub search to find a similar question and didn't find it. - [x] I am sure that this is a bug in LangChain rather than...langchain-ai/langchainChampionsZhangSep 33 weeks ago
Mistral Cloud Chat Model fails in AI Agent: "Failed to parse URL from [object Request]" — still broken in 2.36.9 Cloud (same as #25318)## Describe the problem/error/question Any AI Agent node using the **Mistral Cloud Chat Model** (lmChatMistralCloud) fails on every execution. The agent receives its input correctly (full prompt visible in the model node's input), then the HTTP call to the Mistral API fails...n8n-io/n8nalanwang-collabAug 313 weeks ago
[Feature]: Upgrade XGrammar to >=0.2.4 and expose max_whitespace_cnt### 🚀 The feature, motivation and pitch vLLM currently declares the following XGrammar dependency: The generated test lockfiles currently resolve to: - CPU/CUDA/XPU: `xgrammar==0.2.3` - ROCm: `xgrammar==0.2.1` XGrammar added `max_whitespace_cnt` support for structural tags in...vllm-project/vllmwangxuwAug 313 weeks ago

Companies and products named

Company or productPosts naming it
GitHub3
Hugging Face2
Ollama2
LlamaIndex2
ChatGPT1
Anthropic1
About this problem

Evidence

8 posts from 8 people in 7 places, about 2 a week over 25 days. Mostly on run-llama/llama_index, Hacker News comments, r/LocalLLaMA. Tools named alongside: GitHub, Hugging Face, Ollama, LlamaIndex.

Frustration Frustration 1 of 3· Seen on GitHub issues, Hacker News, Reddit

How it was grouped

Posts that state a pain and match the "structured-output" rule. First post Aug 31, 2026, latest Sep 24, 2026. Corroborated: 3 or more posts from 2 or more people or places. Method

History

  • 2026-09-25 Added: Models fail to return valid structured output (7 posts)

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