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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the tool is known to be safe. The description adds valuable context beyond annotations, such as the 27-year data window, monthly updates, and output fields (volatility_score, premium_change_yoy, etc.). No contradictions with annotations are present.

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 return value, then usage guidance, then update cadence. Every sentence provides distinct, necessary information without redundancy or fluff.

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 read-only, single-parameter tool, the description is largely complete: it lists output fields, methodology, update frequency, and appropriate use cases. It lacks explicit limitations (e.g., US-only, commercial-liability scope) but these are implied by the title, and no output schema exists to add more detail.

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 schema provides 100% coverage for the single optional 'days' parameter, including its purpose, constraints, and behavior (history vs. snapshot, Gold tier requirement). The description does not add extra parameter semantics but is not required to since the schema fully documents it.

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's specific function: 'Returns a 0-100 US commercial-liability premium-volatility score' and lists output fields. It distinguishes itself from siblings by focusing on liability premium spikes and leading indicators of non-ransomware cyber-incident frequency.

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 usage context: 'Call when the user asks about insurance hard markets, liability premium spikes...' and lists specific decision-making scenarios. However, it does not mention alternatives or when not to use this tool, falling short of a full 'when/when-not' distinction.

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