If you’re looking for a significantly cheaper and more customizable option, check out GitHub - transitive-bullshit/OpenOpenAI: Self-hosted version of OpenAI’s new stateful Assistants API
It’s 100% spec compliant with the official OpenAI OpenAPI spec for all Assistant-related resources, so you can use it with the official OpenAI sdks at a fraction of the cost.
The current version still uses OpenAI’s chat completion API under the hood to handle tool invocation and responses, but I plan on adding support for more model providers shortly.