yahoo_mail_stats

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

No annotations are provided, so the description carries the burden. It implies a safe read-only count operation and discloses defaulting behavior (folder defaults to INBOX, account defaults to the one marked default), but never explicitly states it is read-only, requires auth, or what the output shape is.

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 front-loaded summary sentence followed by a compact Args block; every line is useful. Slightly loose as a prose description but appropriately sized for a 2-parameter tool.

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?

With an output schema present, return values need not be spelled out, and the description already names the three stat categories. Both parameters are documented, so the only real gap is the absence of explicit read-only/auth confirmation for a tool with zero annotations.

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, and it does: it defines folder as the mailbox folder with the INBOX default and account as an accounts.json key with examples ('personal', 'work') plus the default rule. That adds real meaning the schema lacks, though formats/valid values remain loose.

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+resource (mailbox statistics) and enumerates what is returned: total messages, recent/unseen counts, date range. This clearly separates it from yahoo_list_mail and yahoo_search_mail, though it never explicitly names a sibling.

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 word 'Quick' and the stats framing imply this is the lightweight summary tool rather than a message-listing tool, but there is no explicit when-to-use vs when-not guidance or named alternative among the many sibling mail tools.

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