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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is clear. The description adds value by listing returned fields (name, address, county, industry sector, closed status) and the data source, enhancing transparency beyond schema.

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 three sentences, each serving a distinct purpose: stating the action, listing outputs, and providing scale/source. It is front-loaded and contains no extraneous information.

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 the presence of an output schema, the description adequately covers inputs and key outputs. It mentions the source and scale. However, it could clarify parameter interaction (e.g., zip overrides state) and whether results are paginated (though limit parameter exists).

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?

With 100% schema description coverage, the description summarizes filtering by state or ZIP and implies the override behavior (ZIP overrides state). This adds context beyond the individual parameter descriptions within the schema.

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 searches EPA Toxic Release Inventory facilities by US state or ZIP code. It specifies the resource (TRI facilities) and the filtering dimensions, distinguishing it from sibling tools like epa.environment.water_systems.

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 searching facilities by location but does not explicitly state when to use this tool over alternatives or provide exclusion criteria. It mentions '600K+ regulated facilities' as context but lacks direct guidance.

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