Ch 3: Planner and Task Graph
By Chapter 3, the genius can already ask for helpful errands. But a bigger request needs more than eagerness.
Imagine tonight's community movie night in the school hall. Families are coming soon, and the room is not ready yet.
If the genius starts shouting errands at random, people will redo work. Chairs might be dragged into the wrong places. The projector might be tested before anyone decides where the screen should go. The walking path might get blocked and need to be cleared again.
So the genius does something smarter first.
They cover a planning board with sticky notes.
One note says inspect the hall. Another says set out the chairs. Another says test the projector and speakers.
Then the genius draws arrows between the notes. Some steps must wait. Others can happen side by side.
That board is the heart of planning. Builders call this kind of note-and-arrow map a task graph.
Why Plan First?
Without a plan, the genius zigzags.
They might ask for chairs before the screen spot is chosen. They might test the projector, move it, and test it all over again. They might forget which prep step is ready and which one still needs to wait.
With a plan, the big request becomes smaller and clearer.
First inspect the hall. Then set out the chairs. Then test the projector and speakers.
The important part is not just the list. It is the waiting rules.
The chairs and the projector test both depend on the hall check. But they do not depend on each other.
That means they can move forward together as soon as the room has been inspected.
Please get the school hall ready for tonight's community movie night.
Put the planning-board steps in the correct order
Drag to reorder, or use Tab + Enter + Arrow keys.
- Break the big job into smaller notes
- Draw arrows for what must wait
- Start the notes that are ready
- Keep blocked notes waiting
- Finish the room prep and report back
Key Insight
The planning board does two jobs.
First, it shrinks a big job into pieces people can actually act on. Second, it marks which pieces must wait and which can move side by side.
The arrows matter.
An arrow means: "do not start this yet."
No arrow means two ready steps can move together.
If two notes point at each other, the board is broken. Everyone would wait forever.
A good planner catches that kind of confusion before the errands begin.
When builders say task graph, this is what they mean: a map of work that shows order, waiting, and chances to move in parallel.
What You Learned
You now understand what the planner adds to the story: before the genius starts acting, they first turn a big request into a map of smaller steps.
That map shows what must go first. It also shows what can move together.
In Chapter 4, the genius learns another skill: how to keep track of long conversations without carrying every scrap of detail forever.
What You Can Do Next
You now have an agent that plans before it acts. It decomposes complex requests into tasks, respects dependencies, and tracks progress. But there is a problem growing quietly in the background: the message array.
Every exchange, every tool result, every planning response — they all accumulate in the conversation history. For a four-task plan where each task takes five turns, that is 40+ messages. The model's memory is finite. Eventually, it will lose track of earlier context or the conversation will simply become too large to handle.
In Chapter 4: Memory, Summaries, and Context Control, you will learn to manage context: truncating old messages, summarizing completed work, and saving checkpoints for recovery.