Microsoft 365 MCP Server

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

While annotations indicate this is a destructive mutation (readOnlyHint: false, destructiveHint: true), the description fails to disclose critical behavioral specifics: the required If-Match/ETag header for optimistic concurrency control, partial update semantics (PATCH behavior), or what happens to unspecified properties.

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?

At seven words, the description is technically concise, but this brevity is wasted on empty content. It is not front-loaded with value—every sentence fails to earn its place by providing only redundant 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 complex mutation tool with nested objects, optimistic concurrency requirements, and specific Microsoft Graph API semantics, the description is inadequate. It omits the ETag requirement, partial update behavior, and Planner-specific context (buckets, assignments, categories) that would help an agent construct valid updates.

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?

With 80% schema description coverage, the schema carries most of the semantic weight. The description adds no parameter-specific guidance, but meets the baseline expectation where the schema documents fields like 'percentComplete', 'dueDateTime', and the ETag requirement.

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 'Update the properties of plannerTask object' is a tautology that restates the tool name with minimal expansion. It fails to distinguish this tool from sibling 'update-planner-task-details' or clarify which properties are updatable versus read-only.

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 like 'create-planner-task', 'get-planner-task', or 'update-planner-task-details'. It omits critical prerequisites such as the requirement to first fetch the task to obtain an ETag before updating.

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