usgs_earthquake_count

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

Annotations already cover readOnlyHint=true. The description adds the behavioral nuance of returning counts rather than full records, which is useful context. However, it does not disclose any additional behaviors such as default date ranges, response format, or handling of empty results, which would be helpful.

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?

Two short sentences effectively communicate the core purpose and a use case. The structure is front-loaded with the main action ('Count earthquakes matching criteria') followed by a concrete example. No wasted words.

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 count tool with well-documented parameters and a readOnly annotation, the description is largely complete. It could explicitly state the return value format (e.g., a number or object), but the verb 'count' strongly implies the outcome. The absence of an output schema makes this a minor gap, but the overall context is sufficient.

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 has 100% parameter description coverage, so the baseline is 3. The description's example (M5+ in 2024) helps map to minmagnitude and starttime/endtime, but this is minor value beyond the schema descriptions already provided.

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 counts earthquakes matching criteria, distinguishing it from sibling tools like usgs_earthquakes that fetch full details. The example 'How many M5+ earthquakes occurred in 2024?' makes the purpose immediately understandable.

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 indicates this is for statistics and explicitly says 'without fetching full details,' implying that the alternative tool should be used when details are needed. However, it does not name the exact sibling tool or provide explicit when-not-to-use guidance beyond that.

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