List users

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

Annotations include readOnlyHint:true, so safety is known, but the description adds no behavioral context. It doesn't mention sorting, pagination, or that omitting query returns all users. The description only restates the username filter already present in the schema.

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?

The description is a four-word fragment, which is concise but under-specified. It lacks the structure of a complete description and doesn't earn its place as a standalone sentence. It could be improved without adding verbosity.

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 clarify what the tool returns, but it doesn't. It also doesn't state whether an empty query returns all users or how the limit interacts. The tool is simple, but this description leaves too much unspecified.

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 schema has 100% coverage for both limit and query, including descriptions. The description's 'User.filter by username' adds no additional parameter semantics beyond the schema, 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?

The description 'User.filter by username' indicates the tool filters users by username, and the title 'List users' clarifies the action. However, the description is a cryptic fragment rather than a complete sentence, so it doesn't fully articulate the purpose on its own. It distinguishes from siblings by the username filter.

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 usage guidance is provided in the description. There are no alternatives mentioned, nor any indication of when to use this tool over other list tools. The usage is only implied by the tool name and the query parameter description.

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