mailkite_list_mailbox_messages

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds useful behavioral context: authentication via app password with `api` scope, management session token requirement, and newest-first ordering. It does not disclose pagination, limits, or return format, but with readOnlyHint present, a 3 is appropriate.

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?

Three sentences with no filler. The core action and ordering are front-loaded, followed by authentication context and a requirement. Every sentence 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 simple read-only list tool with one fully documented parameter and readOnlyHint annotation, the description is nearly complete. It covers purpose, ordering, authentication, and session requirement. The only minor gap is lack of pagination/limit details, but that is not critical for a basic list call.

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%, so the schema already documents the `address` parameter. The description adds that this is a mailbox address and ties it to the agent's own inbox, but it doesn't add format or source details beyond the schema. Baseline 3 is correct.

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 ('List'), a resource ('a mailbox's messages'), and a clear ordering ('newest first'). It distinguishes itself from the sibling mailkite_list_messages by specifying mailbox context and the app-password/API authentication path, though it doesn't explicitly name the sibling alternative.

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 gives clear context: it is how an agent reads its own inbox without an IMAP client, and it requires a management session token. It does not explicitly say when not to use it or name alternatives like mailkite_list_messages, but the context is strong enough for an agent to select it appropriately.

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