List Users

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

Annotations already establish read-only, idempotent, and non-destructive behavior. The description adds valuable behavioral context by specifying the response contents, filtering capability, and the search matching semantics. No contradiction with the annotations exists.

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 three concise, front-loaded sentences. The first sentence states the core action and output shape, the second adds filtering scope, and the third explains the search parameter. Every sentence earns its place with no filler or 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?

Given there is no output schema, the description's explicit statement of return fields is important. With annotations covering safety behavior and the schema covering all parameters, the definition is largely complete. Sort, pagination, and date-range behavior are left to the schema, which is acceptable given their detailed descriptions there.

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 the structured schema already documents all 14 parameters in detail. The description adds little new parameter-level meaning beyond restating the search behavior, which the schema also covers. This is the expected baseline when the schema carries the parameter documentation burden.

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 operation ('List users for a site'), identifies the target resource, and enumerates the returned data: user IDs, session counts, first/last seen dates, and user traits. It also specifies the required site scoping. It does not explicitly differentiate from sibling tools like rybbit_get_user or rybbit_live_users, so it falls just short of a 5.

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 description gives clear usage context: use this to list users for a site and optionally filter by analytics dimensions. It also provides direct guidance for the 'search' param with case-insensitive partial matching. It does not explicitly state when to choose an alternative tool or list exclusions, but the context is strong enough for an agent to select it appropriately.

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