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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds genuinely useful context beyond them: the reply itself lives in the traveller's email, not in the tool result. It does not say what happens if the ticket reference is unknown or expired, which is the remaining behavioral gap for a lookup 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?

Three sentences, front-loaded with what the tool reports, then how to call it, then the alternative. No sentence restates the name or the title, and nothing is padding.

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 carries the return values and does so by enumerating the three possible states, so the agent knows what a result means. Combined with the lookup inputs, an agent has enough to call this correctly without further documentation.

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 baseline is 3, but the description earns above that by stating the either/or coupling between taskId and email that the schema does not express (only ticket is marked required). It doesn't explain what to do when neither is available.

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?

Names the specific resource (a Vuelo support request) and enumerates the exact states it returns: with the team, replied, resolved. This is clearly distinguishable from contact_support, which it names as the way to add to a request, so an agent can route between the two 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 an explicit trigger ('Use it when the traveller asks for an update') and explicitly redirects the add-to-request case to contact_support with the matching booking and reason. Both when-to-use and the alternative are stated rather than inferred.

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