fetch_emails

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

With no annotations, the description must convey behavioral traits. It only states that it fetches and returns data, but does not disclose side effects (e.g., marking reads, pagination, sorting, or effects on mailbox state). This is a significant gap for a tool that may mutate read status.

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 two concise sentences with no redundancy. It is front-loaded with the action and resource, then states the return value. Every word 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?

The tool has no output schema and no annotations, yet the description does not explain return format, pagination, limits, or ordering. It also lacks guidance on when to use it relative to other tools. For a tool with four parameters and no annotations, this is insufficient contextual information.

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 descriptions cover 100% of parameters, so the description adds little value beyond the schema. The description does not explain how parameters interact or the meaning of 'since', 'unseen', etc., beyond their schema descriptions. Baseline 3 is appropriate.

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 states the action (Fetch emails) and the resource (specific mailbox), and mentions what is returned (metadata and content). It is specific and understandable, though it does not explicitly differentiate from sibling tools like search_emails or advanced_search.

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 get_thread. There is no mention of context, prerequisites, or exclusions, leaving the agent without decision support.

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