Get my mailbox settings

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

Annotations already mark the tool read-only and idempotent, and the description adds substantial behavior beyond that: reply bodies are stripped to plain text and truncated to replyBodyChars, scheduled start/end times are only meaningful when status is 'scheduled,' and missing mailboxes surface as a specific 404. This is exactly the contextual detail an agent needs.

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?

Four sentences, each with a distinct job: scope, reply-body behavior, schedule semantics, and error condition. The most decision-relevant information is front-loaded in the first sentence, 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?

Even without an output schema, the description covers what is returned, the only parameter's effect, edge-case semantics for scheduled replies, and the failure mode. Nothing an agent needs to call and interpret this tool correctly is omitted.

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 coverage is 100%, so replyBodyChars is already fully documented in the schema, including the 0-omits-bodies behavior. The description adds that bodies are 'HTML in Graph' and are truncated, but this largely restates the schema's semantics rather than providing new meaning.

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 opens with a specific verb-plus-resource phrase, 'Returns the signed-in user's Outlook mailbox configuration,' and enumerates the exact fields returned. This makes the tool distinguishable from sibling tools like me_get_profile or mail_get_message without inspecting the 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?

It clearly establishes when the tool applies: signed-in user's mailbox settings. It also flags a boundary case with 'Accounts with no Exchange Online mailbox fail with 404 MailboxNotEnabledForRESTAPI,' but it does not explicitly name sibling alternatives or say when not to use this tool.

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