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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior. The description adds substantial context beyond that: returned fields, the bookableViaMcp flag, the fact that services exist even for non-bookable venues, and what id=null means for create_booking.

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 front-loaded with the core purpose and then layers in the critical parameter distinction and return-value caveat. It is somewhat dense and repeats the venue-vs-directory distinction, but every major sentence carries useful operational 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?

Given no output schema and simple annotations, the description covers the purpose, the key parameter behavior, return fields, and the booking limitation caused by bookableViaMcp=false. Nothing essential for correct invocation 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?

With one parameter and 100% schema description coverage, the baseline is 3. The description meaningfully expands on the schema by explaining that place_slug selects a venue rather than the directory site and that only this form's serviceId works with create_booking.

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: listing a venue's services with price and duration. It clearly distinguishes the venue-specific form from the directory-site fallback, so an agent can immediately understand what this tool returns.

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?

Explicitly names search_places as the source for place_slug, says this is what you want in almost every case, and explains why omitting it usually returns unwanted directory-site services. It also ties the venue-specific serviceId to create_booking, giving clear guidance on when and how to use the tool.

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