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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds real behavior beyond them: it discloses the return payload and the non-obvious detail that booking_link is a /go/ redirect carrying src=entityindex, which an agent could not infer otherwise.

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?

One dense but well front-loaded sentence; the core action and scope come first, the enumerated fields after. Slightly cramped as a run-on but there is no filler.

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 no output schema, the description usefully enumerates returned fields, and annotations cover the safety profile. Missing only edge behavior (what happens on an unknown slug, uniqueness guarantees), which is minor for a single-param lookup.

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 0% and the single 'slug' parameter has no description in the schema, so the definition must compensate. It does partially, by naming the slug's origin (search_hotels), but gives no format, case-sensitivity, or exact-match guidance.

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 clear verb+resource ('Full record of one accommodation by slug') and enumerates the payload (location, contact, booking engine, verification status, website, booking_link). The parenthetical '(from search_hotels)' implicitly differentiates it from the search sibling, though it never explicitly says 'use search_hotels for listing'.

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 phrase 'by slug (from search_hotels)' establishes the prerequisite workflow context: you call this after a search produces a slug. It does not state exclusions or failure behavior, but the trigger condition is clear enough to act on.

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