Weather ($0.01)

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

With no annotations, the description bears full burden for behavioral disclosure. It mentions a cost ($0.01 USDC) and implicitly indicates a read operation (conditions and forecast), but does not discuss rate limits, authentication, or any side effects. This is adequate for a simple read tool but not comprehensive.

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 two brief sentences, front-loaded with the core capability and followed by cost information. Every word is functional; no redundancy or filler. Perfect conciseness for a simple tool.

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 straightforward tool with one parameter and no output schema, the description is nearly complete. It explains what data is returned (current + 3-day forecast) and the cost. It does not specify the output format or provide an example, but this is not critical given the simplicity. It is sufficient for an agent to understand and invoke correctly.

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 input schema already covers the single 'city' parameter with an example, achieving 100% coverage. The description adds the context 'any city' and 'for travel & planning', but does not provide additional format or validation rules beyond the schema. Baseline 3 is appropriate as schema does the heavy lifting.

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 clearly states the tool provides 'current conditions + 3-day forecast for any city' for travel and planning agents. The verb is implicit but unmistakable, and the resource (weather for a city) is explicit. It is easily distinguished from all sibling tools, which cover unrelated domains like crypto, extractors, and identity checks.

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 description implies usage for travel and planning agents, but provides no explicit when-to-use or when-not-to-use guidance. There are no sibling weather tools to cause confusion, so the minimal guidance is acceptable but not proactive.

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