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

Annotations already establish read-only, idempotent, non-destructive behavior. The description adds meaningful context beyond these hints: it restricts scope to public handles and explicitly states the tool does not claim, change, or contact an identity, which is valuable behavioral disclosure for safe selection.

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 sentence carries purpose, usage trigger, and exclusions with zero redundancy. The key action and the most important behavioral constraint are front-loaded, and no word is wasted.

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 an output schema present, full parameter documentation, and annotations covering safety, the description is complete for a browse/list tool. The cursor and sort semantics are handled by the schema, and the description covers when and why to use this tool.

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 all four parameters (q, sort, limit, cursor) are already documented with types, constraints, and purpose. The description adds no parameter syntax or semantics beyond what the schema provides, so the baseline of 3 holds.

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 states a specific verb and resource: 'find or browse public Sup handles'. It also explicitly carves out what the tool does not do ('without claiming, changing, or contacting an identity'), which clearly distinguishes it from identity-mutating sibling tools like sup_call_card or sup_probe.

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?

'Use this when the user asks to find or browse...' gives an explicit trigger condition, and 'without claiming, changing, or contacting an identity' provides a clear when-not condition. This effectively routes the agent away from identity-affecting alternatives even though sibling names are not spelled out.

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