Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare this as read-only, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds useful context beyond annotations: results are grouped by PO, the tool never modifies orders, and a connected Forthcast store with sign-in is required.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two focused sentences with no wasted framing. It front-loads the usage condition, then adds the key behavioral and prerequisite constraints.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only list tool with full schema coverage, annotations, and an output schema, the description is complete. It covers scope, exclusions, result grouping, authentication prerequisites, and non-mutation behavior.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents limit, status, and supplier semantics. The description reinforces status and supplier use cases but does not add parameter-level detail such as how the limit applies to grouped results.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description gives a specific verb and resource: listing purchase orders. It enumerates the merchant questions it answers and clearly states results are grouped by PO, making the tool distinguishable from the inventory-analysis siblings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly says when to use the tool, covering ordered/drafted/open/partial/received/cancelled/overdue/expected and supplier-associated questions. It also states when not to use it by clarifying that it does not approve, receive, cancel, or otherwise modify orders.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.