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

Annotations already assert readOnlyHint=true, so safety is covered; the description adds the OAuth-style scope requirement and the semantic boundary of what counts as a blackout (room-level, not property-level). It doesn't discuss result shape beyond the id/date pair, but that plus the scope note is meaningfully beyond the annotations.

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, zero filler: the resource scope comes first and the prerequisite second. Every clause carries information an agent needs to select and call it.

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 2-param read-only list with no output schema, the description compensates by sketching the return shape (room id and date pairs) and the auth scope. Minor gaps remain, such as behavior on empty ranges or any maximum span, but nothing that would cause a mis-call.

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% and both parameters carry their own descriptions plus date-format patterns, so the schema does the heavy lifting. The description only reasserts that the tool operates over a 'date range' without adding boundary or inclusivity semantics beyond 'First date'/'Last date'.

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 (list blackouts) and immediately bounds it: 'room-specific blocked dates (room id and date pairs), not whole-property closures.' This negative definition tells an agent exactly what this tool returns versus a broader closure concept, so it's distinguishable 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?

Gives a concrete prerequisite ('Needs scope read:availability') and rules out whole-property closures, which is a real usage constraint. It stops short of naming an alternative tool for whole-property closures, so the routing is implied rather than explicit.

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