get_messages

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

Annotations already declare readOnlyHint=true, covering the safety profile. The description adds scoping context (inbox vs sent, optional user filter) beyond the annotation, but provides no additional behavioral details such as pagination, ordering, or authentication requirements. With annotations present, this is acceptable but not rich.

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?

The description is a single, focused sentence with no wasted words. It is front-loaded and readable, giving the most important information quickly.

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?

While the output schema and readOnly annotation reduce the burden, the description remains incomplete for effective agent use. The ambiguous 'account' parameter and the lack of differentiation from 'get_inbox' leave important selection and invocation details unresolved.

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 0%, so the description must compensate. It clarifies 'box' and 'from_user' indirectly, but leaves 'limit' and especially 'account' unexplained. The 'account' parameter is ambiguous and could significantly affect behavior, making this insufficiently informative.

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 clearly identifies the resource (message history), the source boxes (inbox or sent), and an optional user filter. It is a clear statement of what the tool does, though it lacks a verb and does not distinguish itself from the overlapping sibling 'get_inbox'.

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 provides no guidance on when to use this tool versus alternatives. Given that 'get_inbox' appears as a sibling and likely overlaps with the inbox capability, the absence of any differentiation or when-to-use/when-not-to-use guidance is a notable gap.

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