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

Annotations already cover readOnly/idempotent/non-destructive/non-open-world, so the safety profile is handled. The description adds real value beyond them: an auth prerequisite ('Requires a connected account and event access') and a privacy guarantee ('Does not expose the host email'), which is exactly the kind of context annotations cannot convey.

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, front-loaded with what is returned, then requirements, then negative scope, then use cases. Every clause earns its place with 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?

For a read-only tool whose safety profile is covered by annotations and with no output schema, the description adequately explains the return payload, prerequisites, and boundaries. The only gap is the unexplained eventId input.

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?

The single parameter eventId has 0% schema description coverage, so the description carries the full burden. It mentions 'event' context and 'event access' but never explains what eventId is, its format, or that it is required, leaving the only input effectively 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?

States a specific verb+resource and even names the return payload ('the event name and your own reply-email suggestion'). It implicitly separates itself from send_host_contact via 'Does not... contact anyone', but never explicitly names the sibling tools it could be confused with.

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 a clear temporal/contextual trigger ('before contacting an event host') and enumerates concrete use cases (volunteering, collaboration, ticket questions, support). It stops short of naming alternatives like prepare_host_contact or send_host_contact or stating when not to use it.

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