list_mailboxes

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

The annotations already declare readOnly, openWorld, idempotent=false, and destructive=false. The description adds meaningful context by specifying that it includes mounted archives and shared stores and does not modify accounts or request access, which goes beyond the annotations.

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 tightly written sentences: the first states what is listed and what is included; the second clarifies what is not done, which prevents misuse. No redundancy or 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?

The description is complete for a no-parameter read-only tool with an output schema. It covers scope, inclusions, and exclusions, and the annotations plus output schema handle the rest.

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?

With zero parameters, the baseline is 4. The description adds no parameter details, but there are none to describe, so this 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?

States a specific verb (List) and resource (mailboxes/stores) with explicit scope: only those accessible via the running Outlook profile. It distinguishes itself from siblings like list_folders and search_emails by naming the exact collection returned.

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?

The description clarifies the implicit boundary by stating it does not add accounts or request access, which helps the agent know this is observation-only. However, it doesn't explicitly tell the agent when to use this versus outlook_status or list_folders.

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