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

Goes well beyond the read-only annotations: booked and blocked times are excluded from results, times are returned as ISO-8601 with offset, the shop timezone is America/New_York, and the endpoint is rate limited per IP and per shop. These are exactly the operational traits an agent needs before calling.

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 trigger condition is front-loaded and most sentences carry distinct facts (exclusions, timezone, non-reservation, rate limits). A few sentences restate format details already present in the schema, which is mild redundancy rather than bloat.

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 an output schema present, return values need no explanation, and the description still covers trigger, exclusions, timezone, dependency on get_business/search_businesses, non-reservation, and rate limits. Nothing needed to invoke it correctly is missing.

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 already 100%, so the baseline is 3; the description adds the semantic role of offering ('selects that shop's rules from get_business') and reiterates the date/start formats and timezone. Most format detail duplicates the schema, but the offering behavior is genuinely new information.

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 ('check availability ... Lists the open 30-minute slots for one shop and one date') and constrains scope to a single shop/date, which clearly separates it from get_booking_status and request_booking. An agent can identify what it returns 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?

'Use this when the user wants to check availability ... before booking' gives clear trigger context, and 'Does not reserve a slot' rules it out as a write path. It does not, however, explicitly name request_booking as the follow-up tool, so the alternative 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.