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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is fully covered. The description's 'Never returns values' adds genuinely useful security context beyond those hints, but says nothing about ordering, pagination, or what it does when no credentials exist.

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 very short sentences, front-loaded with the core action and immediately followed by the most important constraint. Every word earns its place; nothing is padded.

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?

With only two required, fully documented parameters, no nested objects, no output schema, and complete annotation coverage, the description needs little more. The one real gap is that it never clarifies ordering, scoping behavior per environment, or relationship to the set/rotate counterpart.

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 'company' (Summer company ID, UUID format) and 'environment' (staging/production enum) are documented 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?

The description states a specific verb and resource ('List saved credential names, sources and versions') and adds a scoping qualifier ('Never returns values') that tells an agent exactly what data it will and will not get back. It implicitly separates itself from the write counterpart summer_credentials_set, but it never explicitly names or routes to a sibling.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives such as summer_credentials_set for storing or rotating credentials. The only usable signal is the 'Never returns values' note, which hints at a discovery/inspection use case but is not framed as guidance.

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