USGS earthquake feed

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

No annotations are provided, so the description carries the full burden and it does well on the most important trait: it is a paid x402 endpoint costing 0.002 USDC per call on Base, the call is paid automatically when EVM_PRIVATE_KEY is set, and otherwise a 402 payment requirement is returned. This is valuable, non-obvious behavioral disclosure. It still omits rate limits and response characteristics.

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?

Three tight sentences, front-loaded with purpose and then the payment/authorization behavior. No filler, though the first sentence is redundant with 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 single-parameter feed tool with no output schema and no annotations, the description covers the critical thing an agent needs (payment and auth flow). It is nearly complete; only the nature/shape of the returned earthquake data is left unstated.

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% and the schema already enumerates the valid feed values, so the parameter is fully documented structurally. The description adds nothing about feed semantics (e.g., what 'significant_week' vs '4.5_week' returns), so baseline 3 applies.

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 identifies the data source (USGS) and resource (earthquakes) and even the endpoint path, but uses no verb and essentially restates the title 'USGS earthquake feed'. It does not differentiate this feed from the sibling data tools (weather, worldbank, preflight).

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?

There is no guidance on when to use this tool versus siblings, nor which feed to pick for a given need. The only conditional logic given is about payment, not about task selection.

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