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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds the data source (GeoNet, GNS Science), 'no auth required', the time window (last 365 days), result cap (max 100), and the nuance that quakes 'may have caused shaking'. These are useful beyond the annotations.

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 two sentences, front-loaded with the core action and resource, followed by concrete details on output, limits, and data source. Every sentence contributes value, with no redundant or vague wording.

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 search tool with comprehensive annotations and an output schema present, the description is complete: it covers what the tool does, its scope, limits, output fields, data source, and authentication. An agent has all necessary context to decide when to use it and what to expect.

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 fully documents the mmi parameter, including range and meaning. The description repeats the same information (e.g., MMI -1 to 8) without adding significant new semantics beyond what the schema provides. Baseline of 3 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 states a specific action ('Search recent New Zealand earthquakes') with a clear resource and scope, and differentiates itself from siblings like quakes.detail and quakes.stats by focusing on search by minimum shaking intensity. It also lists return fields, making the tool's purpose 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 gives clear context: it searches recent quakes within the last 365 days, filtered by MMI, with a max 100 results. It does not explicitly mention when to prefer this over alternatives like quakes.detail or quakes.stats, but the scope and output are described well enough for an agent to infer usage.

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