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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds useful behavioral context beyond that: the response bundles profile/reputation stats, a page of listings, and a total count, and max_id is framed as a continuation cursor. An output schema exists, so not explaining return shapes is acceptable.

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 sentences, front-loaded with what the tool returns and followed by routing/pagination guidance. Every clause earns its place with no redundancy.

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?

Purpose, sibling routing, and pagination are all covered, and an output schema means return structure needn't be restated. Minor gap: the schema marks max_id as required despite describing it as omit-for-first-page, and the description's 'continuation' phrasing does not resolve that ambiguity.

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 both parameters are already documented in the schema, making 3 the baseline. The description corroborates max_id as a continuation mechanism and username as the lookup key but adds no format or edge-case detail beyond the schema.

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 (Fetch) and resource (a Poshmark seller's public closet) and enumerates exactly what it returns: profile/reputation stats, a page of current listings, and total listing count. It also distinguishes itself from poshmark_search and poshmark_listing by name, so an agent can route without opening a schema.

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?

Explicitly names the alternatives (poshmark_search to find closets, poshmark_listing for one item) and how to continue results (use max_id). The condition selecting each tool is clear, leaving little to inference.

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