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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive; the description adds real behavioral context: the EPA data source, 'no auth required,' the fixed 32-community scope, and the returned fields. This exceeds what annotations and schema alone provide.

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?

Four focused sentences with the primary action and scope first, followed by return shape, usage tip, and source/auth note. No filler or redundant restatement of the title.

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 one-optional-parameter, read-only list/search tool with an output schema and safety annotations, the description covers scope, result contents, workflow position, data source, and authentication. Agents have everything needed to call it 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 fully documents the optional query parameter with filtering semantics and examples, so schema coverage is 100%. The description repeats the filter idea (search) and examples but adds no meaning beyond the schema, yielding the baseline 3.

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 names a specific verb ('List or search'), a bounded resource ('the 32 US communities covered by EPA EnviroAtlas block-group ecosystem-service data'), and the concrete return fields. It positions itself as the entry point for 'the other EnviroAtlas tools,' distinguishing it from the metrics tools without needing to open schemas.

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 'Call this first to find valid community codes/names for the other EnviroAtlas tools,' giving clear when-to-use guidance. It does not name sibling tools or state exclusions (e.g., if you need ecosystem metrics, use enviroatlas.metrics.* instead), so it falls short of a full 5.

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