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

No annotations are provided and the description discloses nothing: not whether it returns indices, scores, or a count; not the detection method; not the input format expectations. The full behavioral burden is unmet.

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?

Duplicated title string with no informational content. It is short but conveys zero value; brevity here reflects under-specification, not conciseness.

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?

A statistical analysis tool with one ambiguous string input, no annotations, and no output schema. The description should explain input encoding and output shape but provides nothing, leaving the agent unable to invoke it correctly.

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?

Only one parameter, 'values', with schema description 'Values to process' at 100% coverage. The schema is minimally informative and the description adds nothing about format (CSV? JSON? newline-delimited?), which is critical since the param is a string that could take many shapes.

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 is 'Outlier Detect: Outlier Detect' – a pure tautology that restates the tool name twice. It gives no verb, no indication of what resource or input it operates on, and no way to distinguish it from statistical siblings like x402-zscore, x402-iqr, or x402-price-anomaly.

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?

No guidance at all on when to use this versus the many statistical/anomaly siblings. An agent has no signal for choosing it over x402-zscore-array or x402-price-anomaly.

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