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

No annotations are provided, so the description carries the full behavioral burden. It helpfully notes the default period (14), but does not state the required input format for a 'price series' string, whether values is mandatory, how a short series or insufficient data is handled, or what the result looks like.

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?

Two tight sentences with the core purpose front-loaded and the default called out immediately. Nothing is wasted, though it is arguably too terse given the missing input-format detail.

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 2-parameter calculation with no annotations and no output schema, the description covers what is computed but omits input encoding (comma-separated vs array) and the return shape. It is minimally adequate but leaves practical call details to guesswork.

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%, so baseline is 3, but the schema's own descriptions are generic ('Values to process', 'Period to process'). The description adds the meaningful detail that period defaults to 14 and that values is a price series, slightly exceeding the schema.

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 specific verb (Calculate) and resource (Relative Strength Index of a price series), and even expands the acronym, so the purpose is unambiguous. It does not distinguish itself from closely related sibling oscillators like x402-stochastic or x402-williams-r, which prevents a 5.

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/when-not guidance and no mention of alternative indicators (sma, ema, macd, stochastic) present among the siblings. The only hint is 'price series' indicating the expected input domain, which is implied context rather than explicit guidance.

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