db-stats

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

Annotations indicate readOnlyHint=true and destructiveHint=false, so the agent knows this is a safe read operation. The description adds value by specifying it returns 'statistics that reflect the use state,' implying metrics like performance or usage data, which goes beyond the annotations. However, it doesn't detail behavioral aspects like rate limits, authentication needs, or specific stat types, keeping it at a baseline 3 with some added context.

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 a single, clear sentence that efficiently conveys the tool's purpose without unnecessary words. It's front-loaded with the core function, making it easy to parse. This earns a 5 for being appropriately sized and structured with zero waste.

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 read-only tool with one parameter and no output schema, the description is adequate but has gaps. It specifies what the tool does but lacks details on the statistics returned, error conditions, or how it differs from siblings. Given the simplicity and annotations, it's minimally viable but could be more complete, scoring a 3.

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 the 'database' parameter fully documented as 'Database name.' The description doesn't add extra semantic details about the parameter, such as format examples or constraints. Given the high schema coverage, the baseline score is 3, as the description doesn't compensate beyond what the schema provides.

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: 'Returns statistics that reflect the use state of a single database.' It specifies the verb ('Returns statistics') and resource ('single database'), making the function evident. However, it doesn't explicitly differentiate from sibling tools like 'list-databases' or 'collection-storage-size,' which could also provide related database information, so it doesn't reach a 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 prerequisites, exclusions, or compare to siblings such as 'list-databases' (which might list databases without stats) or 'collection-storage-size' (which could focus on storage metrics). This lack of context leaves the agent to infer usage, scoring a 2 for minimal guidance.

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