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

Annotations already provide readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds a meaningful behavioral detail that no directory or enumeration is provided, which sets expectations about scope. However, it does not disclose what happens for invalid or unknown IDs, nor explain what 'key lifecycle' entails.

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 short and front-loaded with the primary action, and the second clause adds a scoping caveat. However, it relies on the unexplained term 'key lifecycle', and the brevity actually contributes to the ambiguity. It is compact but not sufficiently clear for a new reader.

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 that there is no output schema, the description should at least summarize what a 'minimized key lifecycle' contains or how to interpret the result. It also does not explain how this tool relates to the more than a dozen sibling identity tools, leaving an agent to guess the difference. The mention of 'no directory or enumeration' is useful but insufficient for a complete picture.

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 schema description coverage at 0%, the description must compensate, but it only calls the parameter an 'opaque Agent ID'—already apparent from the parameter name. It does not describe the format pattern, why the ID is opaque, how to obtain one, or any other semantics that would help an agent fill the parameter correctly.

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 'Resolve one opaque Agent ID to a minimized key lifecycle' which gives a verb and resource, but 'key lifecycle' is an unusual and undefined term that obscures what the returned data actually is. It distinguishes only by saying 'no directory or enumeration is provided', which does not adequately differentiate from sibling tools like get_agent_identity_jwks or export_agent_identity. An agent cannot confidently infer what this tool returns or how it is different.

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 only usage guidance is the negative statement 'no directory or enumeration is provided', implying that this tool works with a single opaque ID rather than lists. There is no explicit guidance on when to choose this tool over the many agent identity-related siblings, no mention of expected caller context, and no when-not-to-use conditions.

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