Microsoft 365 MCP Server

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

While annotations correctly indicate readOnlyHint=true, the description adds useful context about targeting the 'default contacts folder' specifically. However, the trailing incomplete sentence creates ambiguity about cross-user access capabilities, and the description omits details about pagination behavior, rate limits, or the structure of returned contact objects that would help agents predict outcomes.

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 consists of two sentences, but the second is an incomplete fragment ending with a colon that serves no communicative purpose and creates confusion. This structural defect means not every element earns its place, as the fragment promises information it never delivers.

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 read operation with 11 optional parameters and no output schema, the description inadequately explains what constitutes a 'contact collection' (field names, structure) or how pagination behaves with the fetchAllPages option. The incomplete cross-user scenario mention further gaps the coverage of capabilities an agent needs to invoke this effectively.

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 100% schema description coverage across all 11 parameters, the schema sufficiently documents individual fields like filter, search, and fetchAllPages. The description provides no additional parameter semantics beyond the schema, which is acceptable given the high coverage, warranting the baseline score.

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 first sentence clearly states 'Get a contact collection from the default contacts folder of the signed-in user,' providing specific verb and resource. However, the description ends with an incomplete sentence fragment ('There are two scenarios...') that introduces confusion about whether the tool supports accessing other users' contacts without explaining how, and it fails to distinguish from sibling get-outlook-contact.

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 explicit guidance is provided on when to use this list operation versus the singular get-outlook-contact, nor when to apply filter versus search parameters. The incomplete mention of 'two scenarios' for accessing other users' contacts suggests additional usage patterns but fails to articulate them, leaving agents without actionable selection criteria.

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