User Guides

Reasoning

Configure reasoning parsers for models that emit thinking content
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Some models emit reasoning or thinking content separately from their final response. Dynamo can split that output into reasoning_content and normal assistant content by configuring --dyn-reasoning-parser on the backend worker.

Prerequisites

To enable reasoning parsing, launch the backend worker with:

  • --dyn-reasoning-parser: select the reasoning parser from the supported list below
$# <backend> can be sglang, trtllm, vllm, etc. based on your installation
$python -m dynamo.<backend> --help

Some models need both a reasoning parser and a tool call parser. For supported tool call parser names, see Tool Calling.

Supported Reasoning Parsers

The reasoning parser names currently supported in the codebase are:

Parser NameTypical Models / Format
basicGeneric <think>...</think> reasoning blocks
deepseek_r1Models that should treat output as reasoning until </think> is seen, such as deepseek-ai/DeepSeek-R1 style responses
glm45zai-org/GLM-4.5 and GLM-5 style <think>...</think> reasoning blocks
gpt_ossopenai/gpt-oss-*
graniteGranite models that emit Here's my thought process: / Here's my response: markers
kimiKimi models that emit ◁think▷...◁/think▷
kimi_k25moonshotai/Kimi-K2.5* models that require force-reasoning handling for <think>...</think>
minimax_append_thinkMiniMax models that begin reasoning immediately and effectively need an implicit opening <think> tag prepended
mistralMistral reasoning models that emit [THINK]...[/THINK]
nemotron_deciNemotron models that emit standard <think>...</think> reasoning blocks
nemotron_nanoNemotron Nano reasoning output that ends with </think> without requiring a visible opening tag
qwen3Qwen/Qwen3-* style <think>...</think> responses
step3Step-style models that should treat content as reasoning until </think> is seen

Common Parser Pairings

Some models need both parsers configured together. Common pairings include:

  • openai/gpt-oss-*: --dyn-tool-call-parser harmony --dyn-reasoning-parser gpt_oss
  • zai-org/GLM-4.7: --dyn-tool-call-parser glm47 --dyn-reasoning-parser glm45
  • moonshotai/Kimi-K2.5*: --dyn-tool-call-parser kimi_k2 --dyn-reasoning-parser kimi_k25
  • MiniMax M2.1 style outputs: --dyn-tool-call-parser minimax_m2 --dyn-reasoning-parser minimax_append_think

Tool Calling Interplay

Reasoning parsing happens before tool call parsing. If a model emits both reasoning content and tool calls, configure both parsers so Dynamo can first separate reasoning text and then parse tool calls from the remaining assistant output.