Look beyond the single prompt.
When an AI agent can use tools and carry out a sequence of actions, the surrounding conditions matter. PASTAS is a checklist for making those conditions more explicit.
- Purpose and Audience
- What is the task for, who will use the result, and what would a useful result look like?
- Authority
- Which sources can support the answer, and how will the agent make its claims traceable and verifiable?
- Structure and Style
- What form, level of detail, and communication style does the work require?
- Tools and Access
- Which tools and information can the agent use? What is outside its access or scope?
- Accountability and Safeguards
- Who is responsible for the result? Which actions require review or approval?
- Signals and Review
- What evidence will show progress, failure, or a need to stop and revisit the task?
Use it before handing over a task.
For example, an agent helping prepare a literature scan needs more than a topic. It needs a purpose, source boundaries, an output structure, access rules, and a way to flag uncertainty for human review.
Writing down these conditions makes them easier to examine and revise. The checklist supports planning; it does not by itself establish that an agent is safe, reliable, or appropriate for a particular task.