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

Annotations declare readOnlyHint, openWorldHint=false, and idempotentHint, so the safety profile is already covered. The description adds the California/ZIP scoping constraint, which is useful, but doesn't mention rate limits, precision of estimates, or that results are non-binding. With annotations carrying the behavioral load, a 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?

A single, well-formed sentence that front-loads the action and resource with zero waste. Every clause carries information.

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 calculator with no output schema, the description is adequate but leaves gaps: it doesn't explain what the estimate returns, whether it's a range or point value, or any limitations. The agent knows roughly what the tool does but not the shape or reliability of its output.

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 coverage is 67%, so zip and risk_factors are documented in the schema, while home_sqft lacks a description beyond its bounds. The description names 'ZIP code, square footage, and risk factors' but adds no syntax or format detail beyond what the schema already provides. Baseline 3 fits.

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 verb ('Estimate') and resource ('annual home insurance pricing') plus the scope ('California property'). It distinguishes itself from umbrella_calculator and auto_estimates by domain, but does not explicitly name siblings.

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?

No guidance on when to use this tool versus umbrella_calculator or auto_estimates, nor on prerequisites or subsequent steps. The agent must infer usage context entirely.

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