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

Annotations already declare readOnlyHint=true, so the description need not restate safety. It adds a meaningful behavioral caveat: capabilities and names are self-declared and not verified, which is important context for interpreting results. This goes beyond what annotations provide.

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 sentences with no filler: the first states the core action and scope, the second delivers an important caveat. Information is front-loaded and every word 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?

The output schema and readOnlyHint cover return values and safety, but the description leaves all three input parameters unexplained and offers no usage context. It is minimally viable for a no-parameter call, but lacks detail for correct pagination or capability filtering.

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 0%, and the description does not explain the 'after', 'limit', or 'capability' parameters. The word 'capabilities' loosely hints at the capability filter but provides no format, semantics, or pagination guidance, leaving the agent to infer from patterns alone.

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 states a specific verb ('Find'), a specific resource ('opt-in, unexpired mailbox profiles'), and adds scope qualifiers that distinguish it from siblings like get_mailbox or inbox. The purpose is immediately clear and unambiguous.

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?

There is no guidance on when to use this tool versus alternatives, no prerequisites, and no mention of how it fits into a workflow such as requesting connections. The description implies discovery of peers but does not explicitly route the agent toward or away from sibling tools.

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