EPA Air Quality System (AQS) MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It adequately describes the tool's function (list retrieval) and purpose (code lookup), but doesn't mention important behavioral aspects like whether this is a read-only operation, potential rate limits, authentication requirements, or what format the list returns in. The description doesn't contradict any annotations since none exist.

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 perfectly front-loaded with the core purpose in the first sentence, followed by usage guidance and concrete examples. Every sentence adds value without redundancy, making it highly efficient for an AI agent to parse and understand quickly.

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 simple list retrieval tool with 100% schema coverage but no annotations or output schema, the description provides adequate context about what the tool does and when to use it. However, it lacks details about the return format (e.g., JSON structure, whether it's paginated) and doesn't mention authentication behavior despite the parameters suggesting it's needed, leaving some gaps in operational understanding.

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 the input schema already fully documents both parameters (email and key) with their optional nature and environment variable alternatives. The description doesn't add any parameter-specific information beyond what's in the schema, meeting the baseline expectation when schema coverage is complete.

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 specific action ('Get a list'), resource ('all US states'), and output format ('with their 2-digit FIPS codes'). It distinguishes itself from sibling tools by focusing on state listing rather than summary or monitoring operations, and provides concrete examples (California='06') to reinforce understanding.

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 explicitly states when to use this tool: 'Use this to look up state codes for other AQS API queries.' This provides clear context about its purpose as a reference tool for subsequent operations, distinguishing it from data retrieval siblings like aqs_annual_summary_by_state.

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