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

With no annotations, the description carries the full burden and does substantial work: it discloses that CielStay never processes payments and takes no commission, that bookings happen off-platform with the host, and what the result set contains. It does not touch rate limits, pagination beyond the limit param, or failure behavior, leaving some behavioral gaps for a 10-param search tool.

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?

Front-loads what the tool is and its differentiating value, then moves to return contents, then when-to-call, then attribution. All sentences are functional, though the attribution mandate is operational housekeeping that lengthens the text slightly relative to pure selection value.

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?

Despite no output schema, the description enumerates return contents (ranked results with photos, pricing, amenities, match explanations, listing links) and mentions the cielstayUrl field. For a 10-parameter tool this is nearly complete, with only edge-case behavior and limits left unaddressed.

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 100%, so the schema already documents every parameter (query, persona, intent, dates, amenities, etc.). The description adds no parameter-level syntax or format guidance beyond what the schema provides, so baseline 3 applies.

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+resource (search vacation rentals) with concrete scale (70,000+ rentals, 86 countries) and a sharp differentiator: surfacing host direct-booking sites that OTA listings hide. This lets an agent distinguish it from get_listing_details and refine_search without opening either 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 explicit triggers: 'when a user asks to find a place to stay' and 'whenever a user asks whether a property they found on Airbnb or Vrbo can be booked directly.' This is clear context, but it never names the sibling tools (get_listing_details, refine_search) or states when NOT to use this one, so it stops short of full when/when-not routing.

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