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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description only adds the login prerequisite and the implicit dependency on a previously selected worker. It does not describe response format, error behavior, or what happens when required parameters are omitted – useful but limited beyond the structured annotations.

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 sentences with the critical login prerequisite front-loaded and no filler. Every clause adds information, and the purpose is stated clearly and economically.

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?

The definition covers purpose and authentication dependency but, with 8 parameters and no output schema, it does not describe what the returned detail contains, how flags like refund_reflection_yn affect the call, or what the response shape is. This leaves an agent partially in the dark for a tool with this many parameters.

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 carries full parameter documentation. The description adds value by relating worker_record_no, worker_resident_no, and labor_provider_yn to 'a selected worker' and by reinforcing that account_link_id must match the prior login, which helps an agent correctly source parameters from earlier steps.

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 and resource: 'Fetch COMWEL individual billed-premium detail for a selected worker.' That clearly distinguishes it from worker_select (via 'selected worker') and from premium_billing_notice (via 'billed-premium detail'), though it does not explicitly name the sibling tools.

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 clearly states a precondition: 'REQUIRES prior comwel__auth__npki_session__login call with same account_link_id.' This is valuable, but it does not explain when to use this detail tool over sibling tools like premium_billing_notice or how it depends on worker_select beyond the phrase 'selected worker.'

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