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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false. The description adds meaningful provenance (government price transparency platform), confirms figures are actual billed amounts rather than estimates, and warns of several-fold variation between hospitals. It does not describe output format (output schema exists) or auth needs.

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, front-loaded with what the tool returns. The first sentence is somewhat run-on but every clause earns its place by clarifying the split fees and plan payment. No wasted preamble.

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?

Given the output schema handles return values and annotations carry the safety profile, the description supplies necessary domain context: actual government-published bills, hospital-level variability, and a presentation warning. Complete enough for a read-only retrieval tool, though it could note invocation combinations more explicitly.

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 both cert and procedure parameters. The description reiterates the plan-payment aspect of cert but adds no syntax, format, or constraint details beyond what the schema provides. Baseline 3 applies when the schema does the heavy lifting.

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 resource: Hong Kong private hospital billed amounts per procedure, split into doctor and hospital fees, plus what a named plan pays. It clearly distinguishes from estimates ('not an estimate'), but lacks explicit sibling tool names or a leading imperative verb, so it falls short of a 5.

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?

Contrasts with estimates ('not an estimate') and cautions against quoting a single hospital figure without naming the hospital, giving implied usage context. However, it does not name alternative tools (e.g., estimate_renewal, price_plans) or state when to avoid this tool, leaving usage to inference.

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