check_region

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

Beyond the readOnly and openWorld annotations, the description discloses important behaviors: sources are severity-sorted, lane closure types are called out, results are capped for large regions with exact counts, truncation is indicated in the response, and freshness ranges from live CHP to a 5-minute cache.

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 structured, front-loaded with the core purpose, and every subsequent sentence adds distinct value: usage guidance, data categories, valid regions, truncation behavior, and freshness.

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?

Given there is no output schema, the description adequately conveys what the response contains, how items are sorted, and what limitations apply. An agent has enough information to decide when to call it and what to expect.

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 schema provides zero description coverage for the region parameter, but the description fully compensates by listing the valid region names and explaining that an unrecognized region name returns the list of valid regions.

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 and resource: 'Full current-conditions report for a California region.' It clearly distinguishes itself from point-query siblings by stating that it sweeps every source over the whole region at once, and it enumerates the categories it covers.

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 explicitly says to use this for area-scale questions like 'how is the Bay Area?' and contrasts it with 'instead of stitching together point queries.' This tells an agent when to prefer this tool and what alternative pattern it replaces.

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