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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so the safety profile is covered. The description still adds useful behavior: the result is the catalogue's 'actual' services (not a synthesized or cached view) and the call has no side effects on inventory or bookability, and it can legitimately return nothing.

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 tight sentences, zero filler, and the primary purpose is front-loaded before the clarifying 'does not' clause. Every clause earns its place.

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?

An output schema exists, so return-value explanation is not required, and the read-only nature is covered by annotations plus the explicit no-reservation statement. The only meaningful gap is that the lone required parameter is never described, which slightly underspecifies how to invoke it.

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?

There is one required parameter, publicReference, with 0% schema description coverage, so the description must carry the burden. It only indirectly implies the parameter identifies 'the listing' without naming it, explaining its format, or stating where it comes from, leaving the parameter largely undocumented.

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 gives a concrete verb+resource: it returns a listing's actual catalogue services, and it clarifies the scope by specifying 'when one exists.' It's clear enough to distinguish from a booking tool, though it never references the sibling tools because none of them are true alternatives.

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?

It implies the usage condition ('when one exists') and explicitly rules out the adjacent action by stating it does not reserve a slot or claim bookability, which steers the agent away from treating it as a booking call. It stops short of naming an alternative tool for the reserve/book case, so it isn't a full 5.

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