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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is partly covered. The description goes beyond them by explicitly stating it 'Does not create, hold, modify, or cancel a reservation' and that the data matches an anonymous pre-sign-in view, which is genuinely useful context (no auth needed, no side effects). Rate limits and pagination are not mentioned.

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?

Three sentences, front-loaded with the core purpose, then the scope exclusion, then the required inputs. Every sentence earns its place with no redundant restatement of the name.

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 not be described. The description supplies purpose, read-only guarantee, data-source semantics, and required parameters, which is complete for a straightforward availability-lookup tool.

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 0%, so the schema carries no parameter meaning. The description partially compensates by naming the inputs ('a restaurant, date, and party size') and marking restaurantId and date as required, but party_size's role is only implicit and no format hints (e.g., date syntax) are given.

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 ('Read-only bookable reservation timeslots ... currently shows for a restaurant, date, and party size'), which is unmistakably distinct from sibling tools like resy_restaurant (details) or resy_search (discovery). An agent knows exactly what this tool 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?

The description gives clear context for use ('the same availability an anonymous visitor sees before signing in') and scopes it to a known restaurant/date/party size. It does not name alternative siblings or state explicit when-not conditions, but the read-only framing makes the intended use obvious.

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