How to Create an AI Agent for Beginners

Goal: Build an agent that reads your Gmail and creates Notion tasks.

Step 1: Define ONE Task (15 min)

Write: Input → Output → Done criteria. Example: Input: Unread emails with "invoice". Output: Notion DB row with vendor, amount, due date. Done when 90% accuracy on 20 tests.

Step 2: Pick Stack (Beginner)

Option A (No-code): Relevance AI or Lindy. Option B (Low-code): OpenAI Assistants + Zapier.

Step 3: Create Tools

Tool 1: gmail_search(query)
Tool 2: parse_invoice(text)
Tool 3: notion_create(database, properties)
Describe each with: what it does, inputs, when to use, example.

Step 4: Write System Prompt

"You are invoice helper. You never delete emails. You extract vendor, amount. If unsure, ask. Always output JSON."

Step 5: Test with 10 Examples

Log failures. Fix tool descriptions first, prompt second.

Step 6: Add Guardrails

Max 5 steps, $0.10/run cap, human approval for Notion writes first week.

Full code example in Resources.