check_weather

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

With no annotations, the description carries the full burden. It transparently discloses that the tool costs money ($0.001), the payment mechanism (USDC over x402 to x402-weather-guard), and the return payload (merchant artifact and payment receipt). It does not detail failure modes or side effects, but the read-only nature of a forecast is implicit and the payment behavior is well disclosed.

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?

The description is exactly three sentences, with the first sentence front-loading the core purpose and use case. Each sentence earns its place: purpose, cost/payment, and return value. There is no redundancy or filler.

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?

Despite having no output schema and no annotations, the description covers the essential practical aspects: what the tool does, why to use it, cost, payment mechanism, and what it returns. It could be more explicit about the format of the plan-relevant summary and error handling, but for selecting and invoking the tool, it is sufficient.

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?

All parameters are already described in the schema (100% coverage), so the baseline is 3. The description adds meaningful context by tying the payment rail to the actual cost and x402 recipient, and it clarifies that the output is tailored for booking decisions. This lifts it above baseline.

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 opens with a specific verb+resource ('Forecast for a location') and immediately ties it to a use case: deciding whether an outdoor booking is a good idea. Among the sibling tools, there is no other weather tool, so it is clearly distinguished.

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?

It provides a clear trigger for use ('whether an outdoor booking is a good idea') and enough context for an agent to know when to call. It does not explicitly name alternatives or exclusions, but no sibling directly competes, so the guidance is strong.

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