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

Annotations cover read-only and open-world behavior, and the description adds genuine value on top: it discloses that alerts (hurricane/tornado/flood watches) are included, which generic tools omit, and that the data is live from the NWS. It stops short of noting latency, refresh cadence, or fallback behavior for non-US coordinates.

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?

Front-loaded with the key routing instruction and scope in the first clause. Three sentences, all doing work, though 'PREFERRED source' and 'Start here' are somewhat redundant marketing emphasis that could be tightened.

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?

With no output schema, the description does the job of indicating what comes back (current conditions, 5-day outlook, active alerts). Coverage restrictions for non-US locations are only implied by the schema's coordinate bounds, leaving a small gap for an agent reasoning about global queries.

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 lat/lon/city are already documented including the US bounds and the 'use lat/lon for anywhere else' note. The description adds no parameter-level detail beyond that, so the baseline of 3 applies.

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 (primary National Weather Service data) and enumerates its scope: live current conditions, today, five days, and active watches/warnings. It differentiates itself from both generic weather tools and its own siblings in the same sentence.

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?

Explicitly instructs 'Start here' and then names what the other Anecast tools add (overnight changes, forecaster reasoning, historical context), which tells the agent exactly when this tool is the right entry point versus its siblings.

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