1# Tool Use — Ruby
2 
3For conceptual overview (tool definitions, tool choice, tips), see [shared/tool-use-concepts.md](../../shared/tool-use-concepts.md).
4 
5## Tool Use
6 
7The Ruby SDK supports tool use via raw JSON schema definitions and also provides a beta tool runner for automatic tool execution.
8 
9### Tool Runner (Beta)
10 
11```ruby
12class GetWeatherInput < Anthropic::BaseModel
13  required :location, String, doc: "City and state, e.g. San Francisco, CA"
14end
15 
16class GetWeather < Anthropic::BaseTool
17  doc "Get the current weather for a location"
18 
19  input_schema GetWeatherInput
20 
21  def call(input)
22    "The weather in #{input.location} is sunny and 72°F."
23  end
24end
25 
26client.beta.messages.tool_runner(
27  model: :"claude-opus-4-8",
28  max_tokens: 16000,
29  tools: [GetWeather.new],
30  messages: [{ role: "user", content: "What's the weather in San Francisco?" }]
31).each_message do |message|
32  puts message.content
33end
34```
35 
36### Manual Loop
37 
38See the [shared tool use concepts](../../shared/tool-use-concepts.md) for the tool definition format and agentic loop pattern.
39 
40---
41 
42