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

With no annotations provided, the description carries the full behavioral burden, yet it discloses nothing about input constraints, numeric range limits, precision, error behavior, or return format. For a math tool with zero annotation coverage this is a total gap.

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 text is short but that brevity reflects under-specification rather than economy of language; it is a bare name repetition with nothing front-loaded beyond the title.

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?

No annotations, no output schema, and no descriptive content means an agent has no basis for calling this correctly beyond guessing that it computes the nth Catalan number.

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?

There is a single parameter and schema description coverage is 100%, so the schema technically documents 'n'. However, 'N to process' is itself opaque and the description adds no meaning such as whether n must be a non-negative integer. Baseline 3 applies given high coverage.

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 merely restates the tool name ('Catalan Number: Catalan Number') with no verb and no statement of what operation is performed (compute? look up?). It does not distinguish itself from the sibling x402-catalan-series or x402-catalan-number-adjacent tools.

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 when-to-use guidance, no prerequisites, and no mention of alternatives despite the presence of x402-catalan-series and numerous other sequence tools.

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