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

Annotations already cover the safe read-only, idempotent nature, so the description adds value by documenting the JMA intensity scale mapping (10=Shindo1 through 70=Shindo7), tsunami status enum values, and the open-data/no-auth requirement. These are behavioral details beyond what annotations provide, and there is no contradiction.

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 dense but well-structured: main purpose upfront, return fields, filter/sort options, scale mapping, tsunami statuses, and data source. Each sentence adds meaningful information without redundancy, though length is substantial for a 9-parameter tool. Slightly over-specified for the average reader, but not wasteful.

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?

Given the presence of an output schema and annotations covering safety, the description covers the essential operational semantics: fields returned, filtering, sorting, intensity scale, tsunami statuses, and source/auth. It lacks an explicit definition of the 'recent' time window (e.g., last 24 hours) and pagination behavior, but these are minor gaps for a read-only tool with a rich schema.

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%, so each parameter's meaning is already fully documented. The description adds a summary of filterable attributes and repeats the intensity scale mapping (also present in min_scale's schema description) and tsunami statuses, but does not introduce new semantic information beyond what the schema provides. Baseline score 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 clearly states the tool fetches 'recent earthquake reports' from the JMA via the P2PQuake network, listing specific return fields (epicenter, coordinates, depth, magnitude, intensity, tsunami status). This specific verb-resource pairing immediately distinguishes it from siblings like quake_history (historical) and tsunami_warnings (tsunami-specific), even without naming them.

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 guidance on parameter usage (filtering by intensity, magnitude, prefecture, report type; sorting options) and notes the default newest-first order. However, it does not explicitly state when to choose this tool over alternatives (e.g., 'for historical data use quake_history') or set exclusions, leaving tool selection partially to inference.

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