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

With no annotations and no output schema, the description carries the full burden. It does disclose the horizon, 6-hour cadence, scoring inputs, HTTP method, and price ($0.02 via x402), which is genuinely useful. However, it never explains what a 'risk score' means (range, direction, calibration), leaving output interpretation opaque.

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?

Purpose is front-loaded and the trailing bracketed metadata (HTTP verb, price, docs URL) is compact. The first two sentences are largely redundant, restating 'SFO weather delay risk for the next 48 hours' twice, which costs a little efficiency.

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 zero-param, no-annotation, no-output-schema read tool, the description covers what it returns, how it is derived, the horizon, cost, and where docs live. The one meaningful gap is the interpretation of the risk-score output, which nothing else supplies.

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 tool takes zero parameters, so there is nothing for the description to clarify and the baseline of 4 applies. No parameter-level semantics are needed or missing.

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 resource (SFO weather delay risk), a concrete horizon (next 48 hours), the driver inputs (wind gusts, convection, precip, cloud cover) and cadence (6-hour risk scores). It is clearly distinguishable from the generic weather_aviation-delay-risk sibling by being bound to SFO.

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?

The line 'Same shape as the generic delay-risk endpoint, bound to SFO' points the agent at the alternative and the condition that separates them (airport binding). It stops short of an explicit when-not or a rule for choosing among the other airport-specific siblings.

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