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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive behavior. The description adds useful context by revealing that it returns the signed-in user's display name, mail, and UPN. No contradictions or hidden behavioral surprises are apparent.

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 compact sentences with no filler. The first sentence front-loads the action, scope, and output fields; the second gives a practical use case. 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?

For a parameterless, read-only profile fetch with rich annotations, the description covers the core need: what the tool returns and why to call it. It does not describe error behavior or exact value formats, but these are minor given the tool's simplicity and lack of parameters.

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 tool has zero parameters and 100% schema description coverage, so no parameter documentation is needed. Credit is given per the baseline for parameterless tools; the description focuses on output fields, which is appropriate.

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 uses a specific verb ('Get') and resource ('signed-in user's Microsoft 365 / Outlook profile') and enumerates the exact fields returned. It clearly differentiates this from entity/profile-related siblings by emphasizing the signed-in user's own identity.

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 explicitly states when to use the tool: 'Use to confirm whose calendar is connected.' This gives clear context, though it does not name alternatives or exclusions. Still, the use case is actionable and sufficient for a zero-parameter tool.

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