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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the description only needs to add context. It does: it discloses the returned data set and the cost model ('Flat 5 points per successful run'), which annotations do not provide. It stops short of noting auth, pagination, or failure behavior, so not a 5.

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 the action and resource, followed by the concrete return fields and cost note. No filler or redundancy; every clause carries information.

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, the description correctly compensates by listing what the profile contains, and the annotations carry the safety profile. What remains thin is failure behavior (invalid username, private/deleted closet), which an agent might benefit from before calling.

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%, so both parameters are already documented, including the domain enum and the username/URL dual format. The description restates the username-or-URL input but adds no syntax, normalization, or resolution detail beyond the schema. Baseline 3 is appropriate.

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 ('Get a Poshmark seller's public closet profile') and enumerates the returned fields (bio, location, follower/following/listing counts, items sold, activity). The 'by username or URL' phrasing and the profile-shaped return set distinguish it from siblings like run_poshmark_users_search and run_poshmark_users_followers without needing the 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?

The lookup-by-username-or-URL framing implies the usage scenario, but there is no explicit when-to-use guidance, no exclusions, and no named alternatives (e.g., run_poshmark_users_search for discovery vs this direct lookup). Usage is inferred rather than stated.

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