Microsoft 365 MCP Server

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

Annotations provide readOnlyHint=false, openWorldHint=true, and destructiveHint=true, indicating this is a mutating operation that can create new resources and may be destructive. The description 'Creates a new chart' aligns with these annotations by confirming creation behavior, but adds minimal context beyond what annotations already provide. It doesn't specify what 'destructive' means in this context (e.g., overwriting existing charts), rate limits, authentication needs, or response format. With annotations covering the basic safety profile, the description adds some value but lacks rich behavioral details.

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 three words: 'Creates a new chart.' It's front-loaded with the core action and resource, with zero wasted words or redundant information. Every word serves a purpose in communicating the basic function, though this conciseness comes at the cost of completeness.

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 tool with 6 parameters (4 required), nested objects in the body, no output schema, and annotations indicating destructive mutation, the description is severely incomplete. It doesn't explain what a 'chart' means in this Excel context, what data formats are expected for sourceData, what chart types are supported, or what the response contains. The high parameter count and complexity demand more contextual information than the minimal description provides.

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 83%, with 5 out of 6 parameters having descriptions in the schema. The description 'Creates a new chart' adds no parameter-specific information beyond what's already documented in the schema. It doesn't explain the purpose of 'body' properties (type, sourceData, seriesBy) or clarify the relationship between driveId, driveItemId, and workbookWorksheetId. With high schema coverage, the baseline is 3, and the description doesn't compensate with additional semantic context.

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 'Creates a new chart' is a tautology that restates the tool name without adding meaningful context. It specifies the verb 'creates' and resource 'chart' but lacks specificity about what kind of chart (Excel chart) or how it relates to the Excel context implied by the input schema parameters. While it distinguishes from some siblings like 'delete' or 'get' tools, it doesn't differentiate from other creation tools like 'create-calendar-event' or 'create-onenote-page' beyond the chart resource.

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. There are no explicit or implicit instructions about prerequisites, context, or comparisons with other tools. Given the sibling tools include 'format-excel-range', 'sort-excel-range', and 'get-excel-range', there's no indication of when chart creation is appropriate versus other Excel operations. The description offers zero usage guidance.

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