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

With readOnlyHint/idempotentHint already declaring safety, the description still adds real behavioral context: nothing is booked, no data is transmitted, and the human completes the action. That directly addresses the main misuse risk (an agent assuming the tool schedules a meeting). It doesn't mention whether the returned link is language-dependent or how the service fallback behaves, which keeps it below 5.

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 tight sentences: what is returned first, then the non-action clarification, then the optional parameter. Every sentence carries distinct information and nothing is repeated from the schema.

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 zero-required-parameter read tool with an output schema and full annotation coverage, the description covers the only things an agent could get wrong: that it does not book, and where the optional service id comes from. No necessary information is missing.

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%, so the baseline is 3, but the description adds meaning beyond the schema: the service id should come from meom-public-list-services and only yields that service's own link "if it has one" — a conditional return behavior the schema does not express. The lang parameter is left entirely to the schema.

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 first sentence names a specific verb and resource ("Returns the link where a person can book a meeting") and enumerates the other returned values (contact page URL, sales email). It is immediately distinguishable from the list-* siblings, which only enumerate data and never return a booking link.

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 clearly states the tool's scope boundary ("does not book anything or send any data; the person opens the link themselves") and routes the agent to meom-public-list-services when a service-specific link is wanted. It stops short of saying when to prefer this over the other siblings or what to do if no service has its own link, but the calling context is unambiguous.

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