Microsoft 365 MCP Server

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the agent knows this is a safe read operation. The description adds 'Read-only,' which is redundant, and 'Represents a collection,' which implies listing but lacks details on pagination, error handling, or response format. It doesn't contradict annotations, but adds little behavioral context beyond what annotations provide.

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 extremely concise with just one sentence: 'Represents a collection of worksheets associated with the workbook. Read-only.' It's front-loaded and wastes no words, making it easy to parse quickly. Every part contributes, though it could be more informative.

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?

Given the tool's complexity (13 parameters, no output schema) and rich annotations (readOnlyHint, openWorldHint), the description is minimally adequate. It states the purpose but lacks details on usage, behavior, or output. With annotations covering safety, it's not incomplete, but doesn't fully compensate for the missing output schema or parameter guidance.

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 100%, so the schema fully documents all 13 parameters. The description adds no parameter-specific information beyond the general 'collection' context. This meets the baseline of 3, as the schema handles the heavy lifting, but the description doesn't enhance parameter understanding.

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 tool's purpose: 'Represents a collection of worksheets associated with the workbook. Read-only.' It specifies the verb 'represents' (though 'lists' would be more precise) and resource 'worksheets associated with the workbook,' distinguishing it from siblings like 'get-excel-range' or 'format-excel-range.' However, it doesn't explicitly differentiate from other list tools (e.g., 'list-folder-files'), so it's not a perfect 5.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing driveId and driveItemId), compare to other list tools, or specify use cases. The only hint is 'Read-only,' which is covered by annotations, leaving the agent with minimal usage context.

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