Rig v0.33 now available!

[joshua-mo-143]

Hi everyone, Rig v0.33 is available to use!

Let's get right into talking about what's new this version and what's been updated.

New custom MCP Client

Do your MCP servers need to update their tools often? Now you can easily update your agent's tools with our new McpClientHandler, which automatically does this for you. All you need is a ToolServerHandle (created when using ToolServer::run()) and an MCP client. Then simply attach your tool server handle to your agent and you'll be good to go!

System messages

For a long time now, preamble has basically been the default "system prompt" in Rig. Now however, you can also directly insert system messages into your message history (as the first message!) which will make it much easier to print as part of a chat history rather than needing to directly manipulate the preamble itself.

New providers and provider integrations

The following new providers and provider integrations have been added:

• Llamafile
• xAI image gen
• OpenAI Responses API websocket
• Gemini Interactions API

Provider-native tooling support

We now support using provider-native tooling! You can use the tooling that each provider is able to use natively without any interaction required from Rig's side. Simply include it in your request and let the provider do all the work for you.

Cached tokens in telemetry

Cached tokens are now shown in telemetry. Pretty useful for anyone who needs aggregated token counts!

Fixed

• Fixed an issue where deserializing straight to an f64 would break any program using the serde_json/arbitrary_precision feature.
• Fixed an issue where in some cases the OpenAI streaming tool calls would break due to incorrect de-duping logic
• Fixed an issue with Gemini embedding dimensions being hard coded
• Fixed an issue where Gemini URL backed docs were not supported
• Fixed an issue with max_tokens not being forwarded in OpenAI requests
• Fixed an issue with cached_input_tokens not propagated in chat completions streaming
• Fixed an issue with Gemini trying to pass in an invalid tool argument to an MCP tool

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Full changelog: #1489

Thanks for reading! We build rig, rig builds us.