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

No annotations are provided, so the description carries the full burden. It discloses defaults and maximum values for radius_km and days, which is helpful. However, it omits behavioral details such as how results are ordered, any result limits, or the nature of the returned data (though output schema may cover return structure). It is not misleading but lacks depth, scoring a 3.

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: two clear sentences of purpose, then a concise Args block. Every sentence earns its place, though the Args section could be more compact. It is not bloated and remains readable, so a 4 rather than a 5 for slight verbosity.

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 5 parameters, no annotations, and an output schema present, the description covers the parameters and use cases thoroughly. It does not describe return values, but the output schema handles that. It could mention result ordering or edge cases like 'no earthquakes found,' but overall it is complete enough for correct invocation, earning a 4.

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 description includes an Args section that explains every parameter: latitude/longitude with examples, radius_km with default and max, min_magnitude with default, and days with default and max. This adds substantial meaning beyond the input schema, which has no descriptions at all. The schema coverage signal is 0%, meaning the description fully compensates, so a 5 is appropriate.

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 'Get earthquakes near a specific geographic location' and 'Searches for earthquakes within a radius of the given coordinates.' This distinguishes it from siblings like get_earthquake_detail (specific event lookup) and get_recent_earthquakes (recent list, not location-scoped). The verb+resource+scope are specific and unambiguous.

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 provides explicit use cases: 'Useful for assessing local seismic risk or investigating felt reports.' This tells when to use the tool. However, it does not explicitly mention when not to use it or point to alternatives among siblings, so it misses exclusions. Clear context but no exclusions warrants a 4.

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