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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, so the description does not need to restate safety. It adds the slug format example, but no further behavioral traits such as auth requirements, rate limits, or response size are disclosed. This is acceptable given annotation coverage.

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 that states the purpose and gives an example. Every word earns its place; no filler or redundant phrasing.

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 should indicate what the returned profile contains (e.g., name, bio, contact info). It only says 'public profile', which is vague. While the tool is simple, an agent might need to know whether to expect a specific structure. The scope (library user/author) is clarified, but return details are 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?

The input schema has zero description coverage for the slug parameter, so the description must compensate. It provides an example ("dovid-birk") which clarifies the format, but it does not explain how to obtain a slug, what constraints exist, or what the profile contains. The compensation is minimal but helpful.

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?

The description clearly states the tool retrieves a public profile of a library user/author by slug, with a concrete example. It distinguishes itself from siblings like get_author_works (which fetches works) and get_source_sheet (which fetches a sheet) by explicitly scoping to profile data.

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?

No guidance is given on when to use this tool versus alternatives. While the slug example hints at usage, there is no mention of when to prefer this over get_author_works or other user-related tools, nor any exclusions or prerequisites.

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