Class: Candle::Agent

Inherits:
Object
  • Object
show all
Defined in:
lib/candle/agent.rb

Constant Summary collapse

MAX_ITERATIONS = 
10

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(llm, tools:, system_prompt: nil, max_iterations: MAX_ITERATIONS) ⇒ Agent

Returns a new instance of Agent.



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# File 'lib/candle/agent.rb', line 11

def initialize(llm, tools:, system_prompt: nil, max_iterations: MAX_ITERATIONS)
  @llm = llm
  @tools = tools
  @system_prompt = system_prompt
  @max_iterations = max_iterations
end

Instance Attribute Details

#llm ⇒ Object (readonly)

Returns the value of attribute llm.



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# File 'lib/candle/agent.rb', line 9

def llm
  @llm
end

#max_iterations ⇒ Object (readonly)

Returns the value of attribute max_iterations.



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# File 'lib/candle/agent.rb', line 9

def max_iterations
  @max_iterations
end

#system_prompt ⇒ Object (readonly)

Returns the value of attribute system_prompt.



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# File 'lib/candle/agent.rb', line 9

def system_prompt
  @system_prompt
end

#tools ⇒ Object (readonly)

Returns the value of attribute tools.



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# File 'lib/candle/agent.rb', line 9

def tools
  @tools
end

Instance Method Details

#run(user_message, **options) ⇒ Object 



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# File 'lib/candle/agent.rb', line 18

def run(user_message, **options)
  messages = []
  messages << { role: "system", content: @system_prompt } if @system_prompt
  messages << { role: "user", content: user_message }

  iterations = 0
  loop do
    iterations += 1
    if iterations > @max_iterations
      raise AgentMaxIterationsError,
        "Agent exceeded maximum iterations (#{@max_iterations})"
    end

    result = @llm.chat_with_tools(messages, tools: @tools, execute: true, **options)

    if result.has_tool_calls?
      # If the model produced a substantial text answer alongside tool calls,
      # treat it as a final response (model is done, trailing tool calls are noise).
      # Strip <think> blocks so they don't count toward the length check.
      text_without_thinking = result.text_response&.gsub(/<think>.*?<\/think>/m, "")&.strip
      if text_without_thinking && text_without_thinking.length > 50
        return AgentResult.new(
          response: result.text_response,
          messages: messages,
          iterations: iterations,
          tool_calls_made: messages.count { |m| m[:role] == "tool" }
        )
      end

      messages << { role: "assistant", content: result.raw_response }

      result.tool_results.each do |tr|
        tool_name = tr[:tool_call]&.name || "unknown"
        tool_output = tr[:error] ? "Error: #{tr[:error]}" : JSON.generate(tr[:result])
        messages << { role: "tool", content: "[#{tool_name}] #{tool_output}" }
      end
    else
      return AgentResult.new(
        response: result.text_response || result.raw_response,
        messages: messages,
        iterations: iterations,
        tool_calls_made: messages.count { |m| m[:role] == "tool" }
      )
    end
  end
end