Deep reasoning models such as DeepSeek R1, Kimi K2 Thinking, and Qwen 3 do not behave like standard chat endpoints. They emit extended chain-of-thought traces before surfacing a final answer, which introduces failure modes that standard LLM debugging guides rarely address: recursive reasoning loops, tool-use drift, context exhaustion, and structured-output corruption. If you are building agents, coding copilots, or research workflows on top of these systems, you need troubleshooting strategies that match their architecture. Oxlo.ai hosts several of the strongest open reasoning models, including DeepSeek R1 671B MoE, Kimi K2.6, and GLM 5, with request-based pricing that keeps long reasoning traces affordable regardless of input length. The patterns below are drawn from production workloads and apply to any provider, but we will show how to implement fixes using the Oxlo.ai API.
Recursive reasoning loops
One of the most common issues with deep reasoning models is circular reasoning. The model revisits the same sub-problem, re-derives a fact it already proved, or oscillates between two hypotheses without making progress. Unlike standard LLMs, long chain-of-thought models lack an explicit halting mechanism. Without clear stop conditions or external feedback, they treat the context window as an open-ended scratchpad.
To break these loops, enforce a hard turn or token limit inside your application logic. Inject a system instruction that forces periodic summarization, such as: "If you have verified this step in a previous turn, reference it and move forward." You can also implement a meta-prompt that requires the model to label each reasoning step with a checkpoint ID, then deduplicate repeated IDs in your client before sending the next request.
On Oxlo.ai, you can choose models that tolerate longer histories without truncation. DeepSeek V4 Flash supports a 1M context window, and Kimi K2.6 offers 131K context for agentic coding traces. If a
