get_unread_emails

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states 'Fetch' which implies a read operation, but it does not clarify whether fetching unread emails triggers any side effects (e.g., automatically marking them as read). It also leaves 'recent' undefined and does not describe ordering or pagination behavior, leaving significant ambiguity.

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 filler. It is efficiently structured and immediately communicates the core functionality with minimal words.

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 tool with one parameter and no output schema, the description is minimally adequate: it conveys the overall purpose and return type. However, it omits details about 'recent' (time range), default behavior of 'limit', and whether the operation is read-only, leaving gaps that matter for an AI agent invoking it correctly.

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 schema provides 100% coverage for the single 'limit' parameter with the description 'Maximum number of emails to return'. The tool description adds no additional meaning beyond the schema, so the baseline of 3 applies.

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 uses a specific verb ('Fetch') and identifies the resource ('list of recent UNREAD emails'), which clearly distinguishes it from sibling tools like 'list_recent_emails' (which may not filter by unread) and 'read_email' (which fetches a single email). The focus on 'UNREAD' provides a specific scope.

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 guidance is provided on when to use this tool versus alternatives such as 'search_emails' or 'list_recent_emails'. The description does not mention any conditions, exclusions, or context that would help an agent choose this tool over its siblings.

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