list_open_purchase_orders

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

With no annotations, the description carries the full burden. It discloses what fields come back (quantities, unit price), which is useful, but says nothing about whether results are filtered to open lines only, pagination, supplier resolution behavior, or what happens when the supplier is unknown.

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?

A single front-loaded sentence with no filler; the resource and returned fields come first. Nothing redundant or padded.

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?

An output schema exists, so return-value detail is rightly omitted, but the description omits the 'open' filtering semantics that the name implies and that materially change results. For a listing tool whose whole point is scope, that gap is significant.

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 0% for the single 'supplier' parameter, so the description must compensate. It clarifies that the argument scopes results to one supplier, but never states the expected format — supplier ID, code, or name — leaving real ambiguity at call time.

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?

States a specific verb and resource: 'List PO lines for a supplier,' and names the returned fields (ordered/received quantities, agreed unit price). It is not differentiated from the sibling check_invoice, though that tool is unrelated enough that confusion is unlikely. Minor mismatch: the name says 'open purchase orders' while the description says 'PO lines,' without clarifying the relationship.

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?

No guidance on when to use this versus alternatives, no prerequisites, no exclusions. Most notably, the 'open' qualifier in the tool name is never explained — an agent cannot tell whether closed/fully-received orders are included or filtered out.

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