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

Annotations already declare readOnlyHint, and the description usefully adds the security-relevant fact that 'the username and password never leave the vault' plus the exact projection (name and id only). Pagination/ordering behavior is left to the schema, so it is strong rather than complete.

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?

Front-loaded with the resource and the payload projection, then the use case, then the read-only note. Every clause carries information; the parenthetical CLI-comparison is the only marginally expendable element.

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?

For a read-only paginated list with no output schema, the description covers what is returned (name and id, no secrets), the safety profile, and when to reach for it. Only sibling disambiguation against the broader credential/registry listers is missing.

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% — both page and page_size are documented with defaults and bounds in the schema itself. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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 ('stored Helm registry credentials') and narrows the payload to 'name and id only', which is genuinely informative. It does not, however, explicitly distinguish itself from close siblings like list_credentials or list_helm_registries; the 'twin of ankra helm credentials list' CLI reference is an analogy, not a sibling differentiator.

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?

'Use this to name the credential a private registry should connect with' gives a clear, actionable use context. There is no explicit when-not or naming of an alternative (e.g. the generic list_credentials), so it falls short of the 5 bar.

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