Define the Agent's Goal and Scope: Clearly articulate what the agent should achieve and its operational boundaries.
Identify Required Tools: List all potential functions (internal GAS, external APIs) the agent might need to accomplish its goal. Wrap these in GAS functions.
Design the Agent's Orchestration Logic: Determine how the agent will interpret user input, select tools, execute them, and process results. This often involves an LLM for decision-making.
Implement Tool Execution in Apps Script: Write Apps Script functions that represent each 'tool' the agent can use. Ensure they handle inputs and return structured outputs.
Develop the Agent's Decision-Making Core: Use an LLM (e.g., Gemini via Vertex AI) to act as the agent's 'brain.' Prompt it to analyze the goal, available tools, and current state to decide the next action.
Orchestrate Multi-Step Task Flow: Create a loop or state machine in GAS that guides the agent through its process, managing context and tool calls.
Integrate with Google Workspace Services: Connect the agent's actions to specific Google Docs, Google Slides, or other services using their respective Apps Script APIs.
Build a User Interface (if custom Add-on): Design a sidebar or dialog in GAS for user interaction with the agent.
Test, Debug, and Refine Agent Behavior: Iteratively test with various inputs, debug errors, and refine prompts or logic to improve performance and reliability.