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

Annotations already declare readOnly, idempotent, and non-destructive. The description adds meaningful behavioral context by specifying the time periods and status breakdown of the returned counts, which goes beyond the annotations. No caveats (e.g., timezone handling) are mentioned, but annotations cover the safety profile.

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 a single concise sentence that front-loads the key information (booking counts) and adds the relevant breakdown details. No waste 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?

The tool has an output schema, no parameters, and strong annotations. The description sufficiently conveys the purpose and scope for a simple stats tool. It does not explain edge cases (e.g., definition of 'today' or status values), but the output schema and simplicity make this acceptable.

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?

There are zero parameters, so the baseline is 4. The description adds value by explaining what the returned counts represent, though no parameter-specific semantics are needed.

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 tool returns booking counts for today, this week, this month, and broken down by status. It uses a specific verb ('Get') and resource ('booking counts'), distinguishing it from related tools like get_booking_detail or list_bookings.

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 implies the tool is for aggregate summary statistics but does not explicitly state when to use it over alternatives like list_bookings or get_dashboard_stats. No exclusions or alternative recommendations are provided, so the usage context is only implied.

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