x402-is-weird
Is Weird: Check whether a number is 'weird' — abundant (sum of proper divisors exceeds it) but not semi-perfect. Provide value.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| value | No | Value to process |
Is Weird: Check whether a number is 'weird' — abundant (sum of proper divisors exceeds it) but not semi-perfect. Provide value.
| Name | Required | Description | Default |
|---|---|---|---|
| value | No | Value to process |
Changes observed during successful MCP inspections.
Input schema / properties / valueAdded value: +{
+ "description": "Value to process",
+ "type": "string"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full disclosure burden. It supplies the mathematically precise meaning of 'weird' (abundant but not semi-perfect), which is the key context needed to interpret the result, but says nothing about return format, how invalid/non-numeric input is handled, or that the operation is a pure read-only computation.
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?
Front-loaded and efficient: the purpose and the defining conditions are packed into two phrases with no padding. The trailing 'Provide value.' is a wasted, stub-like fragment, which is the only blemish.
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 simple predicate tool with one parameter and no output schema, the description is mostly adequate because the definition of 'weird' is itself the semantic payload. It still leaves the input type/format and the shape of the result (boolean? explanation?) unstated, which matters given the string-typed value parameter.
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% (baseline 3), but the schema text is a generic placeholder ('Value to process') and the description only repeats the stub 'Provide value.' No clarification is added about the string-typed parameter holding a numeric value or about accepted formats.
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?
States a clear verb+resource ('Check whether a number is weird') and goes further by defining the term precisely as abundant but not semi-perfect, which meaningfully distinguishes it from close siblings like x402-is-abundant and x402-is-semiperfect. It stops short of naming those siblings as alternatives, but the conceptual boundary is drawn.
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?
Usage is implied rather than stated: an agent can infer this is for testing a single numeric value for the 'weird' property. There is no explicit when-to-use framing, no guidance on choosing this over the abundant/semiperfect predicates, and no mention of edge cases or input constraints.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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