> ## Documentation Index
> Fetch the complete documentation index at: https://agentclientprotocol.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Model Config Category is stabilized

> Announcement that the model_config session configuration category is now part of the stable ACP protocol.

**Published:** June 24, 2026

The [Model Config Option Category RFD](/rfds/model-config-category) has moved to Completed and the `model_config` category is stabilized.

Agents can use the category for model-related parameters such as context size or speed and quality trade-offs. Clients can then group those options near the primary model selector without depending on Agent-specific option IDs.

For the protocol documentation, see [Option Categories](/protocol/v1/session-config-options#option-categories).