Mixpanel MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. It mentions 'Run an Insights report' which implies execution/processing but doesn't clarify whether this is a read-only operation, whether it requires specific permissions, what the output format might be, or any performance considerations. The 'Flexible analytics query' phrasing suggests some capability but lacks concrete behavioral details needed for proper tool selection.

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 with two brief sentences that don't waste words. It's front-loaded with the core purpose ('Run an Insights report') followed by additional capability context. While it could be more informative, every sentence serves a purpose without unnecessary verbiage.

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 no annotations, no output schema, and multiple similar sibling tools, the description is insufficiently complete. It doesn't explain what an 'Insights report' returns, how it differs from other query tools, what 'flexible analytics' means in practice, or any behavioral characteristics. The agent would struggle to understand when and how to use this tool 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?

The description provides no parameter information beyond what's already in the schema. With 100% schema description coverage (the single parameter 'bookmark_id' is well-described as 'Saved Insights report ID'), the baseline score of 3 is appropriate. The description doesn't add any additional context about parameter usage, constraints, or relationships.

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 states the tool 'Run an Insights report' which provides a basic verb+resource combination, but it's vague about what an 'Insights report' entails. It adds 'Flexible analytics query supporting multiple event types' which gives some context but doesn't clearly distinguish this tool from sibling analytics tools like query_events, query_funnels, or query_profiles. The purpose is understandable but lacks specificity.

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. With multiple query-related sibling tools (query_events, query_funnels, query_profiles, query_retention), there's no indication of what makes 'Insights report' different or when it's the appropriate choice. The mention of 'multiple event types' is too vague to serve as meaningful usage guidance.

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