Mixpanel 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 ranked property names by prevalence, which implies a read-only operation, but it doesn't cover critical aspects like rate limits, authentication needs, error handling, or whether the ranking is based on counts or percentages. This leaves significant gaps in understanding the tool's behavior.

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 and front-loaded, consisting of just two sentences that directly state the tool's function and output. Every word earns its place, with no redundant information or fluff, making it easy for an agent to parse quickly.

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 tool's moderate complexity (2 parameters, no output schema, and no annotations), the description is incomplete. It lacks details on output format (e.g., structure of returned properties), error cases, or performance considerations. Without annotations or an output schema, the agent has insufficient information to fully understand how to interpret results or handle edge cases.

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, clearly documenting both parameters ('event' and 'limit'). The description adds no additional semantic details beyond what the schema provides, such as examples of event names or default values for 'limit'. Given the high schema coverage, a baseline score of 3 is appropriate as the schema handles the parameter documentation adequately.

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 with a specific verb ('Get') and resource ('top properties for a specific event'), and it distinguishes its function from siblings like 'top_events' or 'query_events' by focusing on properties rather than events themselves. However, it doesn't explicitly contrast with all siblings, such as 'list_annotations' or 'segmentation_average', which might involve similar data but different operations.

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 prerequisites, context, or exclusions, such as how it differs from 'query_properties' or other sibling tools that might handle event properties. This lack of usage context leaves the agent to infer appropriate scenarios.

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