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

readOnlyHint=true already covers the safety profile, so the bar is lower. The description adds the response shape including pagination keys (items, count, limit, offset, next_page_url), which is genuinely useful context, but says nothing about default page size behavior, auth, or rate limits beyond what the schema/annotations imply.

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 tightly packed sentences: identity, domain definition, endpoint, and return shape, with the most important naming/definition front-loaded. 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 the return envelope keys, and the schema carries all parameter semantics. It stops short of describing the item shape or how to filter the collection, but an agent has enough to invoke it correctly.

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 limit, offset, and the free-form params passthrough. The description adds nothing about parameter behavior, making the 3 baseline correct.

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 ('List channel listings') and immediately defines the domain term as a property's presence on a listing site like Airbnb/Vrbo, which disambiguates it from siblings such as list_properties and list_listing_sites. The API endpoint reference (GET /v2/listings) further pins the resource.

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?

Listing behavior is implied by the name and the endpoint, but there is no explicit when-to-use vs. get_listing (single item) or list_properties/list_listing_sites, and no guidance on filtering the collection. Usage is inferable, not stated.

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