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

No annotations exist, so the description carries full burden. It discloses a key behavioral trait: 'slot times are returned in the VENUE's timezone, which is not necessarily the directory's.' This adds value beyond the schema. It implies read-only behavior (no destructive hints needed).

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 sentences, front-loaded with purpose, every word earns its place. No redundant 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?

Without an output schema, the description does not explain the return structure (e.g., what each time slot contains). It mentions time slots and timezone but lacks detail on format (start/end, capacity). Given the tool's simplicity, it is adequate but could be more complete.

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. The description adds context: serviceId comes from list_booking_services, date format is reinforced, and place_slug should match that used in the sister tool. This adds meaning beyond the schema descriptions.

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 'Get available time slots for a bookable service on a given date (Wix Bookings).' It uses a specific verb (Get) and resource (time slots) and distinguishes from siblings like list_booking_services (lists services, not slots) and create_booking (creates 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 provides explicit guidance: pass serviceId from list_booking_services, date in YYYY-MM-DD, and use the same place_slug. It also clarifies timezone behavior. It implies when to use (to get available slots before booking) but does not explicitly state when not to use.

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