search_emails

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

readOnlyHint=true already establishes the safe-read profile, and the description adds genuinely useful context beyond it: default limit of 50 returned newest-first, the exact result fields ({id, date, from, subject}), and the follow-up path via read_email(). It does not discuss pagination beyond the limit or rate limits, keeping it short of a 5.

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?

Front-loaded with the purpose sentence, then a scannable Args block, then the return shape and follow-up hint. The args block is long but earns its place given 0% schema coverage; only minor trimming would be possible without losing information.

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 7-parameter read tool with an output schema, the description covers the gaps that matter: folder discovery, date formats, result fields, and the read_email follow-up. The one missing piece is an explicit cross-reference to search_all_folders for cross-folder queries.

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 carry all parameter meaning, and it does: every one of the 7 params is explained, including the folder default and example values, the YYYY-MM-DD date formats, and limit's default and ordering. This fully compensates for the empty schema descriptions.

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 and resource ('Search for emails in a folder') and scopes it to a single folder, which implicitly contrasts with the sibling search_all_folders. However, it never names that sibling, so the distinction is left for the agent to infer from names alone.

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?

Gives concrete routing context: directs to list_folders() to discover folders and to read_email() with the id for full content. It does not explicitly state when to prefer search_all_folders over this single-folder tool, so the alternative is only implied.

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