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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds genuine behavioral context beyond them: name filters are applied server-side, so the returned total is exact without paging through everyone.

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?

Front-loaded with the primary list behavior before the single-record mode, and every sentence carries content. The example-question run is slightly verbose but earns its place by doubling as usage guidance.

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. Between the description's mode coverage, filter semantics, count exactness, and the fully documented schema, an agent has everything needed to call this correctly.

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 coverage is 100%, so baseline is 3, but the description adds value by clarifying the two usage modes, noting that when `id` is supplied the person comes back 'in full (phone, start date)' and that the other arguments are then ignored. This is real semantic layering on top of the schema.

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?

States a specific verb and resource plus its two modes: listing active team members with titles/departments/reporting and the matching total, or reading one person in full by id. No sibling tool overlaps with staff, so an agent can route correctly without opening the schema.

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?

Maps concrete user questions ('who is on the team?', 'who reports to whom?', 'find someone by name') directly to this tool, which is strong intent routing. It stops short of naming when NOT to use it or any alternative tool, but no sibling competes for these queries.

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