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Tools

Tools let the agent take actions. The LLM decides which tool to call and with what arguments.

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Registering Tools

Pass tools to the Tools collection: 
use Cognesy\Agents\Core\Collections\Tools;
use Cognesy\Agents\Core\Tools\MockTool;

$calculator = MockTool::returning('calculator', 'Performs math', '42');
$tools = new Tools($calculator);
// @doctest id="22fb"

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Using FunctionTool

Wrap any callable as a tool. Parameter schema is auto-generated from the function signature: 
use Cognesy\Agents\Core\Tools\FunctionTool;

$tool = FunctionTool::fromCallable(
    function (string $city): string {
        return "Weather in {$city}: 72F, sunny";
    }
);

$tools = new Tools($tool);
// @doctest id="e9cb"

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Agent with Tools

use Cognesy\Agents\Core\AgentLoop;
use Cognesy\Agents\Core\Collections\Tools;
use Cognesy\Agents\Core\Data\AgentState;

$loop = AgentLoop::default()->withTool($tool);

$state = AgentState::empty()->withUserMessage('What is the weather in Paris?');
$result = $loop->execute($state);
// LLM calls the weather tool, gets result, then responds
// @doctest id="06c9"

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How It Works

  1. LLM sees tool schemas and decides to call a tool
  2. ToolExecutor runs the tool with provided arguments
  3. Tool results are formatted as messages and fed back to the LLM
  4. LLM uses the results to formulate a final response
  5. Loop continues until LLM responds without tool calls