Station 02 · The Anatomy Wall

The five parts every agent shares.

Strip the marketing language away and every agent has the same five parts. If you can describe these five things for one of your own tasks, you have an agent spec.

Every agent reads one thing, decides one thing, and posts one thing.

Pip beside a small wall clock floating in the air.

01 · Trigger

When does it run? Pick one: a schedule (every weekday at 07:30), an event (a new ticket arrives), or a person asking (someone clicks a button).

→ Your first agent should run on a schedule. Event-driven is a year-2 problem.

02 · Read

Where does it look? Name the sources in plain language: an inbox, a database, a spreadsheet, a folder.

→ If you can't name the source in one sentence, the data isn't ready yet.

Pip holding a magnifying glass over a small stack of pastel papers.

Pip holding a small mint shield in a gentle protective stance.

03 · Guard

When should it refuse? When the inputs look wrong, missing, or impossible. This is the part everyone skips and regrets.

→ Every guard you write here saves you from one future embarrassing post.

🤖

Pip thinks…

The Guard is the most important part. Without one, an agent will publish garbage with full confidence. Write one more guard than you think you need.

04 · Compute

What does it actually do with the input? Summarise, compare, classify, decide, draft.

→ If you can't write the rules in plain English, you can't write them at all.

Pip in a thinking pose with a small lightbulb in a thought bubble above its head.

Pip releasing a paper airplane toward a small chat bubble.

05 · Post

Where does the answer go? One destination, one message. A Slack channel, an email, a doc, a CRM field.

→ One destination only. Multi-channel agents fail twice as often.

A worked example

The same five parts, for one real agent.

Here's an "Inventory Watchdog" agent dissected. Any business that buys and sells physical product could build this one.

Worked example

The Inventory Watchdog agent

Trigger

Every weekday at 07:00 [your timezone]

Read

Current stock per SKU, last 14 days of unit velocity, supplier lead times

Guard

Refuse if stock table hasn't refreshed since last close

Compute

Days-of-cover per SKU. Flag where cover < lead time. Top 15.

Post

→ One message to your team's #purchasing channel

One agent, one job.

Try this, before you scroll on

Fill in five lines for one of your tasks.

Pick the repetitive thing you held in your head from Station 01. Try to write down its Trigger, Read, Guard, Compute, and Post in a single sentence each. If you can do that, you can build it. If you can't, you've found which part needs more thought.

You finished Station 02

Anatomy Apprentice

Second sticker. Seven more to collect.