# Data Designer's Config Builder

Use [DataDesignerConfigBuilder](#data_designer.config.config_builder.DataDesignerConfigBuilder) to construct [DataDesignerConfig](data_designer_config.md#data_designer.config.data_designer_config.DataDesignerConfig) objects. The builder accumulates model configs, tool configs, column configs, constraints, seed settings, processors, and profilers.

Inputs can come from scratch, a `dict`, [BuilderConfig](#data_designer.config.config_builder.BuilderConfig), a local YAML/JSON file, or an HTTP(S) YAML/JSON URL via [`from_config()`](#data_designer.config.config_builder.DataDesignerConfigBuilder.from_config). Use [`build()`](#data_designer.config.config_builder.DataDesignerConfigBuilder.build) to create a [DataDesignerConfig](data_designer_config.md#data_designer.config.data_designer_config.DataDesignerConfig), or [`write_config()`](#data_designer.config.config_builder.DataDesignerConfigBuilder.write_config) to serialize the current builder config to YAML or JSON.

!!! info "Model config loading"
    [DataDesignerConfigBuilder](#data_designer.config.config_builder.DataDesignerConfigBuilder) accepts model configs as a list of [ModelConfig](models.md#data_designer.config.models.ModelConfig) objects, a YAML/JSON config path, or `None`. When `model_configs=None`, the builder loads default model configs if Data Designer can run locally; otherwise initialization raises BuilderConfigurationError. Model configs define the aliases referenced by model-backed columns such as [`LLMTextColumnConfig`](column_configs.md#data_designer.config.column_configs.LLMTextColumnConfig), [`LLMCodeColumnConfig`](column_configs.md#data_designer.config.column_configs.LLMCodeColumnConfig), [`LLMStructuredColumnConfig`](column_configs.md#data_designer.config.column_configs.LLMStructuredColumnConfig), [`LLMJudgeColumnConfig`](column_configs.md#data_designer.config.column_configs.LLMJudgeColumnConfig), [`EmbeddingColumnConfig`](column_configs.md#data_designer.config.column_configs.EmbeddingColumnConfig), and [`ImageColumnConfig`](column_configs.md#data_designer.config.column_configs.ImageColumnConfig).

::: data_designer.config.config_builder