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

Annotations already declare readOnlyHint=true, so the read-only nature is known. The description adds non-obvious behavioral context: data source (keyless USGS), aggregation method (z-scored vs trailing baseline), refresh cadence (daily), and the list of output fields. It does not contradict annotations or omit critical side effects.

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?

Three sentences: first states purpose and outputs, second gives usage triggers, third states update frequency. No filler, front-loaded, with each sentence earning its place.

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 read-only tool with one optional parameter and no output schema, the description covers the output fields, input semantics via schema, use cases, data source, calculation, and refresh cycle. The only minor omission (Gold tier requirement for history) is captured in the parameter schema, so the context is complete.

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% for the single optional parameter 'days', which is well-documented in the input schema. The main description does not add further parameter semantics beyond noting the current snapshot vs. daily history distinction, but the schema already conveys this. Baseline 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 opens with a specific verb and resource: 'Returns a 0-100 seismic-catastrophe risk pulse' and details the calculation inputs (global M5.5+ frequency, energy release) and output fields. This clearly distinguishes it from generic risk or earthquake tools among the large sibling set.

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?

Explicitly states when to call: 'when the user asks about earthquake activity, seismic risk, or catastrophe-insurance exposure, or when timing cat-bond positions, reinsurance renewals, or earthquake-coverage decisions.' This is direct invocation guidance with concrete trigger scenarios.

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