06.02 · Concept
Thinking out loud, on purpose
Use a scratchpad so the model's reasoning is inspectable rather than implied.
A scratchpad makes an agent write its working assumptions, planned steps, trade-offs and checks before producing an answer or taking an action. It turns hidden inference into something reviewable, so you can spot weak assumptions, missing cases and bad plans while there is still time to correct them.
What this lesson answers
- how should agents use a scratchpad
- when should model reasoning be made visible
- does showing reasoning make agents more reliable
Notes
A scratchpad is a place where the model writes intermediate thoughts before committing to an answer or action. For a software engineer, think of it like making implicit control flow explicit: instead of asking for a final output and hoping the model privately inferred the right steps, you ask it to list assumptions, break the job into subproblems, compare options, and then produce the result. The point is not magic intelligence; it is observability and structure.
The concrete mental model is a work log beside the final response. If the model is debugging, the scratchpad might contain…
Common questions
- What is a scratchpad in an agent workflow?
- A scratchpad is a separate working area where the model records intermediate reasoning before returning a final result or choosing a tool call. It can include assumptions, candidate approaches, evidence, risks, checks and discarded options. The main benefit is not deeper intelligence, but making the model’s path easier to inspect and correct.
- When should I ask a model to use a scratchpad?
- Use a scratchpad when the task is ambiguous, multi-step, risky or expensive to fix after the fact. It is useful for debugging, planning changes, comparing designs and coordinating tool use. For trivial lookups or simple transformations, asking for detailed working can add noise without improving the result.
- Does visible reasoning mean the answer is correct?
- No. A model can produce a neat-looking rationale that is still incomplete or wrong. Visible reasoning helps because it gives you something to challenge: assumptions, missing constraints, weak evidence and unsafe next steps. Treat the scratchpad as review material, not proof that the final answer is valid.
Short definition: what is Thinking out loud, on purpose?