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

Beyond the annotations, the description explains the intensity threshold, the Atkinson & Wald basis, the meaning of 'not_yet_reported', the handling of smaller nearby quakes, source provenance, last-confirmed timing, and links to USGS Did You Feel It? and event pages. It also explicitly disclaims predictions and warnings and names ShakeAlert and MyShake as warning sources.

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 front-loaded with the core purpose and answer states, then adds useful caveats and provenance. It is somewhat long and includes some repeated provenance/link information, but most sentences earn their place.

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?

With no output schema, the description carries the burden of explaining return states and does so thoroughly: yes, not_yet_reported, no, too-small nearby events, source metadata, and safety disclaimers. For a seven-parameter read-only query tool, this is sufficiently complete.

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 71%, so most parameters are already documented in the input schema. The description adds context about 'a few minutes ago' and location-based intensity, but it does not add parameter-specific syntax or usage details beyond what the schema provides.

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 states a specific function: checking whether USGS has recorded an earthquake that could have caused recently felt shaking at a location. It clearly distinguishes this from sibling tools by framing the tool as a personal 'did I feel it?' check rather than a general earthquake search or detail lookup.

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 gives a clear usage context: someone who felt shaking a few minutes ago and wants to know if an earthquake explains it. It does not explicitly name alternative sibling tools or say when not to use this one, but the intended scenario is unambiguous.

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