certificate_status

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

Annotations already indicate readOnlyHint and idlempotentHint. The description adds valuable context: uses native API (no PEM parsing), returns specific fields, and orders results by expiry. It explains the behavior beyond what annotations provide.

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 well-structured with a header, context, return fields, and parameter explanations. Each sentence is informative and concise, with no redundancy.

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 exists, the description sufficiently covers return values and behavior. It explains the purpose, impact, ordering, and API source, making it complete for an agent to select and invoke correctly.

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?

Even though schema coverage is 0%, the description explains all three parameters: warn_days (default 30), target (optional), and limit (max rows). It adds meaning beyond the schema by stating defaults and behavior.

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 checks ESXi management certificate expiry, specifies it's a READ operation, and explains the consequence of expired certs. It distinguishes from sibling tools by focusing on certificate status specifically.

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 implies proactive use to prevent outages but does not explicitly contrast with sibling tools. However, the context of checking cert expiry is clear, and the return ordering (soonest-to-expire first) guides use.

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