How do I pick a model that is not in the list?

From version 1.9.16 every model field lets you type. Click in the field, type the model name and press Enter. This works for OpenAI (and any server set with a Base URL), for Ollama (for example a ":cloud" model), for Claude when it uses another server, and for OpenRouter (type the id as vendor/model-id). The list under the field filters as you type, and you can move through it with the arrow keys. For Gemini, Grok and Claude on the official Anthropic address the field only accepts models from the list, so that a typing mistake cannot break a generation.