Introduction to model.yaml

Draft

model.yaml describes a model and all of its variants in a single portable file. Models in LM Studio's model catalog are all implemented using model.yaml.

This allows abstracting away the underlying format (GGUF, MLX, etc) and presenting a single entry point for a given model. Furthermore, the model.yaml file supports baking in additional metadata, load and inference options, and even custom logic (e.g. enable/disable thinking).

You can clone existing model.yaml files on the LM Studio Hub and even publish your own!

Core fields

model

The canonical identifier in the form publisher/model.

model: qwen/qwen3-8b

base

Points to the "concrete" model files or other virtual models. Each entry uses a unique key and one or more sources from which the file can be fetched.

The snippet below demonstrates a case where the model (qwen/qwen3-8b) can resolve to one of 3 different concrete models.

model: qwen/qwen3-8b
base:
  - key: lmstudio-community/qwen3-8b-gguf
    sources:
      - type: huggingface
        user: lmstudio-community
        repo: Qwen3-8B-GGUF
  - key: lmstudio-community/qwen3-8b-mlx-4bit
    sources:
      - type: huggingface
        user: lmstudio-community
        repo: Qwen3-8B-MLX-4bit
  - key: lmstudio-community/qwen3-8b-mlx-8bit
    sources:
      - type: huggingface
        user: lmstudio-community
        repo: Qwen3-8B-MLX-8bit

Concrete model files refer to the actual weights.

metadataOverrides

Overrides the base model's metadata. This is useful for presentation purposes, for example in LM Studio's model catalog or in app model search. It is not used for any functional changes to the model.

metadataOverrides:
  domain: llm
  architectures:
    - qwen3
  compatibilityTypes:
    - gguf
    - safetensors
  paramsStrings:
    - 8B
  minMemoryUsageBytes: 4600000000
  contextLengths:
    - 40960
  vision: false
  reasoning: true
  trainedForToolUse: true

config

Use this to "bake in" default runtime settings (such as sampling parameters) and even load time options. This works similarly to Per Model Defaults.

• operation: inference time parameters
• load: load time parameters

config:
  operation:
    fields:
      - key: llm.prediction.topKSampling
        value: 20
      - key: llm.prediction.temperature
        value: 0.7
  load:
    fields:
      - key: llm.load.contextLength
        value: 42690

customFields

Define model-specific custom fields.

customFields:
  - key: enableThinking
    displayName: Enable Thinking
    description: Controls whether the model will think before replying
    type: boolean
    defaultValue: true
    effects:
      - type: setJinjaVariable
        variable: enable_thinking

In order for the above example to work, the jinja template needs to have a variable named enable_thinking.

Complete example

Taken from https://lmstudio.ai/models/qwen/qwen3-8b

# model.yaml is an open standard for defining cross-platform, composable AI models
# Learn more at https://modelyaml.org
model: qwen/qwen3-8b
base:
  - key: lmstudio-community/qwen3-8b-gguf
    sources:
      - type: huggingface
        user: lmstudio-community
        repo: Qwen3-8B-GGUF
  - key: lmstudio-community/qwen3-8b-mlx-4bit
    sources:
      - type: huggingface
        user: lmstudio-community
        repo: Qwen3-8B-MLX-4bit
  - key: lmstudio-community/qwen3-8b-mlx-8bit
    sources:
      - type: huggingface
        user: lmstudio-community
        repo: Qwen3-8B-MLX-8bit
metadataOverrides:
  domain: llm
  architectures:
    - qwen3
  compatibilityTypes:
    - gguf
    - safetensors
  paramsStrings:
    - 8B
  minMemoryUsageBytes: 4600000000
  contextLengths:
    - 40960
  vision: false
  reasoning: true
  trainedForToolUse: true
config:
  operation:
    fields:
      - key: llm.prediction.topKSampling
        value: 20
      - key: llm.prediction.minPSampling
        value:
          checked: true
          value: 0
customFields:
  - key: enableThinking
    displayName: Enable Thinking
    description: Controls whether the model will think before replying
    type: boolean
    defaultValue: true
    effects:
      - type: setJinjaVariable
        variable: enable_thinking

The GitHub specification contains further details and the latest schema.