CockroachDB MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions that the tool returns 'Statistics about performance and latency (e.g., P50, P99),' which gives some insight into output behavior, but it doesn't cover critical aspects like whether this is a read-only operation, if it requires specific permissions, potential rate limits, or how it interacts with the database (e.g., if it runs queries or analyzes logs). For a tool with no annotations, this leaves significant gaps.

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 appropriately sized and front-loaded: the first sentence states the purpose clearly, followed by structured sections for args and returns. Each sentence adds value, with no redundant information. However, the formatting with separate 'Args:' and 'Returns:' sections is slightly verbose compared to a more integrated narrative, but it remains efficient.

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 performance analysis tool with 2 parameters), no annotations, and no output schema, the description is moderately complete. It covers the purpose, parameters, and return values, but lacks details on behavioral traits (e.g., safety, side effects) and doesn't fully explain how to interpret the statistics or handle edge cases. It's adequate as a minimum viable description but has clear gaps for effective tool use.

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 adds meaningful context beyond the input schema. The schema has 0% description coverage, providing only titles and types. The description explains that 'query' is a 'Query string to filter' and 'time_range' is for 'Time range for analysis' with a default and format example ('minutes:seconds'), which clarifies their purposes and usage. This compensates well for the low schema coverage, though it could be more detailed (e.g., explaining filter 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: 'Analyze query performance statistics for a given query or time range.' It specifies the verb ('analyze') and resource ('query performance statistics'), making it easy to understand what the tool does. However, it doesn't explicitly differentiate from sibling tools like 'explain_query' or 'get_query_history', which might also relate to query analysis, so it doesn't reach the highest score.

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 sibling tools like 'explain_query' (which might analyze query plans) or 'get_query_history' (which might retrieve past queries), leaving the agent to guess based on names alone. There's no explicit context or exclusions provided.

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