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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutation risk is covered. The description adds real value beyond that: it explains that previous credentials are replaced (invalidated) and that attached deployments must be redeployed to pick up new S3_* env vars — an operational consequence the annotations cannot convey.

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?

Three tight sentences: what it does first, then when to use it, then a critical operational caveat. Every sentence carries distinct information with no filler.

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 destructive mutation with no output schema, the description covers the action, the two motivating scenarios, and the follow-up redeploy requirement. It could note whether the newly generated credentials are returned to the caller, but that is a small omission against otherwise strong coverage.

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 coverage is 0% for the single bucketId parameter, and the description only implies its meaning via 'per-bucket.' The parameter is self-evident from name and context, so the description neither compensates nor misleads, landing at the minimum-viable baseline.

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: 'Generate fresh per-bucket MinIO service-account credentials, replacing the previous ones.' This clearly separates it from siblings like nexusai_bucket_create (creates a bucket) or nexusai_bucket_attach (attaches an existing one), so an agent can disambiguate without opening a schema.

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?

Gives two concrete when-to-use triggers: migrating legacy buckets off shared root creds and responding to a credential leak. It does not name an alternative tool to prefer in any scenario, but no obvious sibling overlaps this rotation behavior, so the gap is minor.

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