get_unread_emails

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

With no annotations, the description carries the full behavioral burden and mostly does not: it never states that this is a read-only operation, what happens with pagination or truncation, whether results are capped, or what the returned list contains. Only the 'unread' and 'inbox' scope is conveyed.

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?

One compact sentence with the resource and scope front-loaded; nothing is wasted, though it is arguably under-specified rather than optimally concise.

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 one-parameter read tool with no output schema the description is minimally viable, but it omits the behavior of max_results and any notion of result ordering or limits, which an agent would want before calling.

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?

The single parameter max_results has 0% schema description coverage, so the description is the only possible place to explain it, yet it says nothing about the parameter. Its default of 5, valid range, and unit of measurement are all left undocumented.

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 (fetches) and resource (unread emails) scoped to the user's inbox, so the operation is unambiguous. It does not explicitly differentiate from the sibling create_draft_reply, though the sibling's purpose is obviously distinct.

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?

No when-to-use or when-not-to-use guidance is given, nor is any prerequisite (e.g., authentication, mailbox state) mentioned. The agent must infer that this is the right call whenever unread mail is needed.

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