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

Annotations already declare readOnly, openWorld, idempotent, and non-destructive hints. The description adds that no auth is required and lists the data sources (GDACS, JTWC, USGS, etc.), which is useful context. It does not disclose any additional behavioral traits like pagination or rate limits, but given the annotations cover safety, a score of 3 is appropriate.

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 a well-organized paragraph that front-loads the core purpose, then filters, then use cases, then data sources. It is slightly longer than strictly necessary but every sentence adds value. The structure is logical and easy to scan, earning a 4 rather than a 5 due to minor redundancy.

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 an output schema present, the description does not need to explain return values. It covers the primary use, filters, intended use cases, data sourcing, and auth requirements. It does not mention detailed parameter interactions (e.g., days overrides start/end), but the schema covers those. The description is complete for a list tool with rich annotations.

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 the schema already fully documents each parameter. The description adds high-level context like 'date range' and 'bounding box' and explains the meaning of 'open' vs 'closed' in status, but this does not go beyond what the schema provides. Baseline 3 is correct.

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 specific verb 'Retrieve' and the resource 'natural disaster and extreme weather events tracked by NASA EONET'. It lists the returned data (geolocation, magnitude, data sources, category) and the tool's name aligns perfectly with its function. It stands apart from siblings like eonet.events.detail or eonet.events.categories based on the 'list' scope.

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 clear context: 'Ideal for real-time situational awareness, disaster monitoring, and geospatial analysis' and enumerates the filtering capabilities. However, it does not explicitly mention when NOT to use it or point to alternatives (e.g., for a single event's full details, use eonet.events.detail). The overall guidance is solid but not fully differentiating.

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