Get Mailbox Connection

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, and the description adds real context beyond them: this is a credential-validation read that returns team, label, permissions and authorised mailboxes, and needs no mailbox storage access. The ETag/304 recheck behavior lives in the schema rather than the description, which is a minor omission but not a gap the annotations leave open.

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, no filler. The core action and the list of returned data come first, and the precondition (no mailbox selection needed) follows as a qualifying clause. Nothing is repeated and nothing needs trimming.

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 tool is a simple read with zero required parameters, an output schema, and four annotations covering safety. The description explains what is validated and what is read back, which is enough for correct invocation. It could go further by naming the failure or error behavior for an invalid credential, but nothing essential is missing.

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 100%: the single optional If-None-Match parameter is fully documented in the schema, including the 304 no-body outcome. The description adds no parameter-level detail of its own, which is the expected baseline when the schema already does the work.

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 names a specific action and resource: validating the Mailbox credential and reading its team, connection label, permissions and authorised mailboxes. It is concrete and lists what comes back. It does not, however, distinguish this tool from close siblings such as mailbox_get_session or mailbox_get_me, so an agent cannot fully tell them apart from the text alone.

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 sentence 'No mailbox selection or mailbox storage access is required' gives a useful precondition: the call works at the connection level without picking a mailbox. That implies when the tool applies, but it never explicitly states when to choose it over mailbox_get_session or mailbox_get_me, which cover overlapping ground.

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