Examples / Getting Started / Hello World

Hello World

Has SpecsRequires API Keys

A minimal Tactus program demonstrating the core workflow without the formal `Procedure` structure. This example shows how to: - Define an agent with a provider and model - Write simple Tactus code that just returns an agent call - Include an embedded BDD specification with Gherkin syntax - Use fuzzy matching to validate agent responses flexibly

Source Code

World = Agent {
  model = "openai/gpt-4o-mini",
  system_prompt = "Your name is World."
}

Specification([[
Feature: Hello World

  Scenario: Greeter returns greeting
    Given the procedure has started
    And the message is "Hello, World!"
    And the agent "World" responds with "Hello! I'm World, nice to meet you!"
    When the procedure runs
    Then the output should fuzzy match any of ["Hello", "Hi", "Hey"] with threshold 0.9
]])

local result = World({message = "Hello, World!"})
return (result and (result.output or result)) or ""

Quick Start

Run the example:

$tactus run 01-getting-started/01-hello-world.tac

Test with mocks:

$tactus test 01-getting-started/01-hello-world.tac --mock

Note

This example requires API keys. Set your OPENAI_API_KEY environment variable before running.

View source on GitHub →

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