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

Annotations already declare this a safe, idempotent, read-only operation, so the safety bar is low. The description adds genuinely useful context beyond them by disclosing billing behavior ('1 point per returned record'), which the annotations do not cover. It stops short of noting pagination or result-ordering behavior.

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?

Two short sentences with no filler; the purpose is front-loaded and the billing note follows. Every sentence earns its place.

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 full parameter coverage, the description is nearly sufficient for a simple read tool. The only remaining gap is any hint about result ordering or how 'related' is determined, which is minor for this complexity.

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 item, domain, and max_items are already documented in the schema with defaults and bounds. The description only echoes the item parameter's id-or-URL flexibility, adding no new syntax or format detail, so baseline 3 applies.

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: listings that Poshmark shows as related to a given listing. It clearly distinguishes itself from run_poshmark_items_search by being relationship-based rather than query-based, though it does not name the sibling explicitly.

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?

Usage is implied by the input ('by listing id or URL'), so an agent can infer that it needs an existing listing. However there is no explicit when-to-use guidance, no mention of when to prefer run_poshmark_items_search, and no prerequisites stated.

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