Online-booking availability

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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds the return vocabulary (open / few_left / full), which is genuinely useful behavioral context, but says nothing about freshness, scraping cost, rate limits, or failure modes for a live third-party booking calendar.

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 compact clauses, each one mapping a calling pattern to a result shape, with the no-parameter case front-loaded. No filler or restated metadata.

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 lookup with no output schema and only three parameters, the description covers the result shape well enough to call the tool correctly and interpret the response. Minor omissions are the restaurant_url requirement (already in the schema) and any note on how stale the availability data may be.

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 only 33% (only restaurant_url is documented), so the description must carry weight — and it does, explaining the compositional semantics: date alone yields party-size availability, date+party yields bookable times. Format constraints (YYYY-MM-DD, party 1-50) are left entirely to the schema.

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 states exactly what the tool returns at three ascending levels of detail (calendar day status, party sizes for a date, bookable times for date+party), which is a precise resource statement rather than a restatement of the name. It does not explicitly differentiate itself from sibling find_available_restaurants, which is the main remaining gap.

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 'With date:' / 'With date and party:' construction effectively tells the agent which call shape to use for which question, which is real usage guidance baked into the parameter documentation. It stops short of stating when to prefer this over find_available_restaurants or prepare_booking.

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