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

No annotations are provided, so the description must fully disclose behavioral traits. It states that the tool returns the three quartiles, which describes output but does not mention input format, sorting behavior, handling of even vs odd dataset sizes, or rounding. This leaves critical behavioral expectations unspecified.

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 only two sentences and mostly to the point, front-loading the operation and then adding the input/output note. The leading 'Quartile:' prefix is redundant with the tool name, but it does not significantly bloat. It is sufficiently compact.

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?

There is no output schema, so the description must explain return values; it says 'returns the three quartiles' but does not state the order or structure of the returned values (e.g., array, tuple, object). The input format is also underspecified, leaving an agent uncertain how to pass the dataset. With these gaps, the description is not complete enough for reliable usage.

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?

Schema description coverage is 100% with a single 'data' parameter described as 'Data to process'. The description adds 'Provide values', which clarifies that data should be the dataset values, but it does not specify the expected format such as comma-separated list, JSON array, or whitespace-separated string. Given the schema already describes the parameter, baseline 3 is appropriate.

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 uses a specific verb 'Calculate' and identifies the resource as 'quartiles (Q1, Q2 median, Q3) of a dataset', which clearly conveys what the tool does. The leading 'Quartile:' label is redundant with the tool name, but the rest adds detail. It does not explicitly differentiate from siblings like median or percentile, though the specificity of the three quartiles helps.

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?

There is no guidance on when to use this tool versus alternatives such as get_stats, median, percentile, or iqr, which are common sibling tools. The phrase 'Provide values' only implies that the dataset is passed as input, but there is no explicit context about when this tool is preferred or when another should be selected. This is a notable gap given the large number of similar statistical tools in the sibling list.

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