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

Annotations already cover readOnly/idempotent/openWorld, so the bar is lower, yet the description adds meaningful non-obvious behavior: no authentication required, page size is unstable, and ranking/activity changes can move records between pages. That pagination-instability warning is genuinely valuable for an agent iterating pages.

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?

Five dense sentences, each carrying distinct information (exclusions, filter semantics, pagination, instability, auth). Front-loaded with the scoping rule; minor ordering could be tighter but almost no waste.

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?

An output schema exists so return values need no explanation, and the description covers auth, filtering, and pagination caveats well. It falls short only on sibling differentiation versus list_agents and on explaining limit/status.

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 0%, so the description must carry parameter meaning. It clarifies capability (filters on currently available capabilities) and cursor reuse (next_cursor), but says nothing about limit or the status enum values, leaving half the parameters unexplained.

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 name and title state a specific verb+resource ('list/find active agents') and the description clarifies scope by naming what is excluded (expired and offline presence). It does not, however, distinguish this tool from the closely named sibling list_agents, so an agent must infer the difference.

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?

Provides concrete usage instructions for pagination (reuse next_cursor with identical filters and sort) but gives no guidance on when to choose this over list_agents or get_agent, nor any exclusions. Usage is implied rather than stated.

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