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

Annotations already declare readOnly, idempotent, closed-world, non-destructive, so the safety profile is covered. The description adds real value beyond them by enumerating the returned content (identity, public links, biography with sources, added statement) — useful since no output schema exists. It does not say what happens for an unknown slug.

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 zero filler; the scope and returned payload come first. Slight terseness as a noun fragment rather than a full clause is the only cost.

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?

For a simple one-parameter read tool with full annotations and no output schema, describing the returned content is the main remaining burden and the description meets it. Only the unknown-slug/error behavior is unaddressed, which is a minor gap.

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?

With only one parameter and 0% schema description coverage, the description does the minimum by tying 'slug' to the collector identifier. It does not clarify slug format or provenance (URL path form vs. internal id), so an agent still has to guess what a valid slug looks like.

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 the specific resource (a collector profile) and its scope (one, by slug), which is enough to distinguish it from list_collectors and search_works without opening the schema. It lacks an explicit verb ('retrieve/fetch'), so the operation is implied rather than stated.

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 phrase 'by slug' hints at the precondition, but there is no explicit when-to-use guidance, no exclusion, and no named alternative such as list_collectors for enumeration or search_book-style lookup. The agent must infer that this is a single-record fetch keyed on a known slug.

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