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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds meaningful context beyond that: output is a directional band, not a bindable quote, and this tool never initiates shopping or purchase. It does not mention return shape beyond 'pricing bands,' which is acceptable given no output schema.

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?

Two tightly written sentences with no filler, and the research-only scoping is front-loaded before the exclusion clause. Every clause earns 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?

Without an output schema, the description should clarify return semantics and the input dimensions, but with 11 mostly undocumented parameters and a missing 'coverage limit' input, the picture is incomplete. It does correctly signal that results are estimated bands rather than quotes.

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?

With 11 parameters and only ~9% schema description coverage, the description carries most of the burden but only gestures at 'household risk factors.' It never explains the individual risk inputs (jet_skis, drivers_under_22, moving_violations, etc.) or their units, and it references a 'coverage limit' dimension that has no corresponding parameter in the schema.

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?

States a specific verb and resource ('Research-only estimate of annual personal umbrella pricing bands') plus the dimensions it varies over (coverage limit, household risk factors). It is clearly distinguishable from the umbrella_consumer_* siblings, which shop/bind/pay rather than estimate.

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 gives both the when ('use this for directional pricing') and the when-not ('not when the shopper wants Coverage Cat to shop for or buy umbrella insurance'), functionally routing the agent away from the consumer flow tools. Nothing is left to inference about the intended scenario.

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