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

Annotations already establish readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds two non-obvious behavioral facts: times are expressed in the pro's local time zone, and no ShearQuery account is required to call it. It still says nothing about return shape or result limits, but the added context is substantive.

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?

Dense but front-loaded with no filler: the action, the when-formats, the time-zone caveat, and the auth note all arrive in order of query value. Sentence two is slightly overloaded with alternatives, but every clause carries information.

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?

For a read-only availability query with an output-less schema and only three parameters, the description covers inputs, time semantics, and auth requirements adequately. The remaining gap—what the returned time slots look like—is minor given there is no output schema and the tool is a simple query.

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 33% (only "when" is documented in the schema), so the description must compensate and only partly does. It richly enumerates accepted "when" values (today/tomorrow/week/date/range) and clarifies pro_id as an id from find_pros_to_book or a booking handle, but leaves "service" undefined as to whether it expects a name, id, or category.

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+resource: returns open (bookable) times with a named pro for a given service. An agent can immediately tell this is an availability-query tool. It does not, however, distinguish itself from the sibling find_open_times, leaving the reader to infer which availability tool applies.

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 embeds workflow context by naming the source of the required id ("id from find_pros_to_book, or their booking handle"), which tells the agent what to call first. It gives no explicit when-not guidance or a stated contrast with find_open_times, so it is clear context without exclusions.

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