Search Microsoft 365 Mail

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

No annotations are provided, so the description carries the behavioral burden. It discloses the auth requirements and hints at cross-folder search via the Chinese intent '跨文件夹搜索邮件'. It does not mention return format, pagination, or side effects, but for a read-only search tool, the provided info is reasonable.

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 short sentences plus a concise list of Chinese intent examples. It is front-loaded with the core action and includes no redundant fluff. Every sentence serves a purpose.

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 search tool with three parameters and no output schema, the description covers the core purpose, syntax, auth, and some usage examples. Gaps include absence of pagination guidance or result format expectations, but overall it is minimally adequate.

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 coverage is 100% for all three parameters, providing baseline 3. The description adds value beyond the schema by clarifying the query uses Microsoft Search syntax and supports cross-folder search, giving agents better context for constructing the query parameter.

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 states 'Search mailbox messages with Microsoft Search query syntax,' which is a specific verb and resource. It clearly identifies the tool as a mail search operation and differentiates it from other search tools via the explicit query syntax mention.

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 description includes prerequisite roles ('Requires both mcp.search and mcp.mail roles') and gives Chinese intent examples that imply usage scenarios. However, it does not explicitly compare with siblings like mail_search_messages or state when not to use this tool.

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