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

No annotations are provided, so the description carries the full burden. It mentions '5 free trial calls per signed wallet,' which hints at an x402 payment/auth flow, but says nothing about output shape, behavior with small or unsorted datasets, or what happens once the free quota is exhausted.

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?

It is short and front-loaded, with the core purpose in the first clause. The only waste is the near-duplicate phrasing of name and sentence, plus the marketing-style trial line, but neither bloats the definition.

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 compute tool with no annotations, no output schema, and an undocumented input format, the description should at minimum explain the expected input encoding and the five returned statistics. Neither is present, so an agent cannot confidently construct a call.

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 0% and the single parameter 'values' is an untyped-in-practice string with no explanation in the schema. The description does not state whether it expects a comma-separated list, JSON array string, or whitespace-delimited numbers, leaving a real ambiguity an agent must guess at.

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 restates the tool name almost verbatim: 'Five Number Summary: Five-number summary of a dataset.' It names the resource (a dataset) and implies a statistical summary, but never enumerates the five values (min, Q1, median, Q3, max) and gives no differentiation from the many statistical siblings such as x402-iqr, x402-quartile, x402-percentile, or x402-stats.

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 versus the numerous other summary/quartile tools in the sibling list, and no prerequisites stated. The only extra sentence concerns a free trial quota, which is pricing information rather than usage guidance.

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