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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds two things beyond them: the exact field set returned and that the call is free (no billing cost). It does not explain how the limit behaves or whether results are truncated, which keeps it from a 5.

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?

Two short sentences with no filler; the field list and the query semantics are front-loaded. The opening is a noun fragment rather than an action statement, a minor structural weakness.

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 does supply the shape of returned records, which is valuable. But for a paginated list tool it omits default page size, max cap, and whether more results exist beyond the limit — information an agent needs to page 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 0%, so the description should compensate. It does explain 'query' (name and email matching) but says nothing about 'limit' (default 50, max 200), leaving half the parameters undocumented anywhere.

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?

Names the resource (people in the company directory) and enumerates the returned fields (id, name, email, title, department, sign-in status), which makes it distinguishable from directory_get_user and directory_list_groups. It stops short of an explicit verb form ('List ...'), but the intent is unambiguous.

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 never says when to use this vs. directory_get_user for a single person, hr_list_people, or admin_list_people. The only guidance-adjacent statement ('query searches names and emails') is parameter behavior, not usage context.

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