Microsoft 365 MCP Server

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

Annotations already declare this is destructive (destructiveHint=true) and not read-only. Description adds minimal behavioral context—doesn't explain ETag concurrency control (If-Match), what constitutes success (especially with excludeResponse), side effects on the parent message, or return values.

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?

While brief, the description wastes words on filler ('for me') and unexplained technical terms ('navigation property'). Single-sentence structure front-loads implementation detail (navigation property) rather than user value (attachment deletion).

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?

Insufficient for a destructive operation with concurrency controls. Lacks explanation of the ETag workflow (obtain from get-mail-attachment, required for If-Match), error scenarios (already deleted attachment), or output behavior despite having no output schema defined.

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%, so the schema fully documents all 5 parameters including If-Match and the boolean flags. Description adds no parameter-specific guidance (e.g., explaining ETag usage or when to exclude responses), warranting the baseline score for high-coverage schemas.

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?

Description states the tool deletes attachments, but obscures this with technical jargon ('navigation property') that lacks explanation. Fails to distinguish from sibling delete-mail-message (which deletes entire messages vs. attachments). The phrase 'for me' is vague filler that doesn't clarify 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 provided on when to use this tool versus alternatives, prerequisites (e.g., needing to retrieve attachmentId first), or concurrency requirements (If-Match header). No mention of relationship to get-mail-attachment or add-mail-attachment siblings.

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