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> For full documentation content, see https://docs.nvidia.com/nemo/datadesigner/llms-full.txt.
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# Seeds

Seed configs declare existing data used as input during generation. A `SeedConfig` combines a seed source with optional row sampling and selection settings. Seed source objects declare where seed data comes from; the engine reads them through seed readers.

Use these objects with `DataDesignerConfigBuilder.with_seed_dataset()`. Related pages: [Seed Datasets](/concepts/seed-datasets) and [seed readers](/code-reference/engine-extension-api/seed-readers).

Built-in seed sources include local files, Hugging Face paths, in-memory DataFrames, directories, file contents, and agent rollout traces. Plugin seed sources can extend the same discriminated union through the plugin system.