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 full burden. It discloses authentication behavior (environment variable fallback), date constraints (same calendar year), and return content (detailed monitor information). However, it doesn't mention rate limits, error handling, or pagination behavior, which would be helpful for a data retrieval tool.

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 well-structured with clear sections (purpose, parameters, note) and every sentence adds value. It could be slightly more concise by integrating the parameter examples more tightly, but overall it's efficiently organized and front-loaded with the core purpose.

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 tool with 8 parameters, no annotations, and no output schema, the description does a good job explaining inputs and purpose. However, it lacks information about the return format/structure, error conditions, or data volume limitations, which would be important for proper agent usage.

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?

Despite 100% schema description coverage, the description adds significant value by providing common parameter code examples (e.g., 44201 for Ozone), clarifying date format requirements, and giving concrete examples of state/county codes. This goes well beyond the schema's basic descriptions.

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's purpose with specific verb ('Get') and resource ('air quality monitors at a specific monitoring site'), and distinguishes it from siblings by focusing on monitors rather than summaries or sample data. It also specifies what information is returned (location, operational dates, measurement parameters).

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 context through the parameter explanations (e.g., 'must be same calendar year'), but doesn't explicitly state when to use this tool versus alternatives like 'aqs_monitors_by_county' or 'aqs_monitors_by_state'. It provides authentication guidance but no comparative usage guidance.

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