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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the date range scope and product constraint, plus the return format ('timestamped sensor readings'), but does not disclose date formatting, units semantics, or station ID requirements. With annotations in place, this is adequate but not exceptional.

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?

A single, front-loaded sentence states the action, resource, scope, and product list, then adds a brief return-value note. No wasted words or irrelevant details.

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?

Output schema and annotations cover return values and safety. The description captures the core purpose but omits details on optional parameters (units, time_zone) and parameter formats, which are relevant for correct invocation. Adequate for a simple fetch tool, but with gaps for full agent self-sufficiency.

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 coverage is only 17% (product has an enum description). The description adds the product list and implies date range, but does not explain station ID format, begin/end date format, units options, or time_zone semantics. Low schema coverage demands more compensation than provided.

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 uses a specific verb 'Fetch' with a clear resource 'meteorological observations from a NOAA station' and scope 'over a date range for a specific product'. It lists all product options, distinguishing it from sibling tools like water_level or currents that retrieve different data types.

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?

Usage context is implied by the description: use when you need meteorological observations for a station/date/product. However, it does not explicitly mention when not to use it or name alternative tools, relying on the agent to infer from the product list and sibling names.

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