Fellow MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool returns 'email addresses of people who were invited to the calendar event', which adds some context beyond basic purpose. However, it lacks critical details: it doesn't specify if this includes optional attendees, the response format, error conditions, or any rate limits. For a read operation with no annotation coverage, this is insufficient.

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 concise and front-loaded, stating the purpose in the first sentence and adding return details in the second. Both sentences earn their place by clarifying scope and output. However, it could be slightly more structured by explicitly mentioning the two parameter options, but it's efficient overall.

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 complexity (a read operation with two parameters, no output schema, and no annotations), the description is incomplete. It doesn't cover key aspects: it lacks output format details (beyond 'email addresses'), doesn't explain parameter usage or conflicts, and omits behavioral traits like error handling. For a tool with no structured output or annotations, more context is needed to be fully helpful.

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?

The input schema has 100% description coverage, with clear parameter descriptions. The tool description adds no parameter-specific information beyond implying that participants are retrieved for a meeting. It doesn't explain the relationship between 'note_id' and 'meeting_title' (e.g., if one is required, or how conflicts are handled). Given the high schema coverage, the baseline is 3, and the description doesn't compensate with additional semantics.

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: 'Get the list of participants/attendees for a meeting.' It specifies the verb ('Get') and resource ('participants/attendees for a meeting'), and distinguishes it from siblings like 'get_meeting_summary' or 'get_meeting_transcript' by focusing on attendees. However, it doesn't explicitly differentiate from 'get_meetings_by_participants' (which might find meetings by participants rather than participants by meeting), 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 when to prefer 'note_id' over 'meeting_title', or how it relates to siblings like 'get_meetings_by_participants' or 'search_meetings'. There's no context on prerequisites, such as needing a synced meeting, which is implied but not stated.

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