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

With no annotations provided, the description carries the full burden, and it discloses essentially nothing: it does not state that the operation is a pure read/compute, does not describe input formatting (comma-separated? whitespace? individual numbers?), and does not describe the return value. It is not contradictory, merely silent.

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, but the brevity reflects under-specification rather than efficiency — the second half of the sentence is a verbatim restatement of the first half. No sentence earns its place beyond naming the operation.

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 one-parameter computational tool with no annotations and no output schema, the description should at minimum state the expected input encoding and what is returned. Neither is present, so an agent cannot invoke it reliably despite the tool's simplicity.

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?

The single parameter has schema coverage, so per the baseline rule this scores 3 even though the description adds nothing. Worth noting the schema's own text ("Values to process") is a placeholder that never explains how to encode multiple values in the string, so no source documents the input format.

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?

"Sum Squares: Sum of squares." is a tautology — it restates the tool name without adding a verb, resource scope, or any distinguishing detail. It does not differentiate this tool from the near-identical sibling x402-sum-of-squares, leaving the agent to guess which one to pick.

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, no conditions, and no mention of the obvious alternative x402-sum-of-squares or x402-sum-of-squares-adjacent tools. The agent receives nothing to route on.

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