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

Annotations already declare this as a read-only, idempotent, non-destructive, closed-world listing. Beyond that, the description discloses meaningful domain behavior: which warehouse categories are structurally ineligible to be PO destinations, and which flags the response carries. No output schema exists, so this disclosure genuinely adds value rather than repeating structured data.

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?

Three sentences, front-loaded with the core purpose before the filter and the PO-destination rule. Every sentence carries information, though the type enumeration is duplicated verbatim from the schema and could be trimmed.

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?

With no output schema and only one optional parameter, the description compensates well by naming the two decision-relevant response flags and their business implication for PO destination selection. It still doesn't say what the remaining warehouse fields look like, but nothing essential to correct invocation is missing.

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 coverage is 100% and the schema's own description already enumerates the accepted type values (direct, 3pl, supplier, amazon_fba, virtual). The description restates the same list and adds only the word "optionally". Baseline 3 is appropriate; the schema does the heavy lifting for this single parameter.

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 all available warehouses") plus the optional scope of filtering by type. There is no competing warehouse listing tool among the siblings, so the purpose is unambiguous and the agent can tell exactly what it gets.

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 gives a concrete downstream usage rule: when resolving a purchase order destination, only offer warehouses where "can_be_po_destination" is true, and explains why supplier/Amazon FBA warehouses are excluded. It does not name an explicit alternative tool or say when not to call this, but the context is clear.

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