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

Goes well beyond the annotations (readOnlyHint=false, destructiveHint=false, idempotentHint=false): it discloses the exact safe rotation sequence, that the bucket and files are untouched, that presigned URLs signed with the old key stop working, and the deploy-in-progress behavior where handover occurs only when the deploy finishes (status rotating). That is precisely the operational context an agent needs before invoking a credential rotation.

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 purpose and the leak scenario, then the safety sequence. Every sentence carries distinct information, though the sequence, presigned-URL, and deploy paragraphs could be tightened slightly for a five-sentence description.

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?

An output schema exists, so return values need not be described, and the description still covers async status ('rotating'), downtime guarantees, and side effects. Nothing an agent needs to call this correctly 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 coverage is 100% and the single project_id parameter is already documented, so the schema carries the burden. The description only adds the constraint 'Pass only project_id', which restates what additionalProperties=false already enforces and adds no new semantic detail.

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+resource ('Replace a project's bucket access key') and the exact scenario that motivates it. It is clearly distinguishable from siblings such as add_storage, remove_storage, and set_storage_visibility, which touch the bucket rather than its credentials.

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 an explicit trigger: 'use it at once when the key may have leaked (printed, logged, pasted, or committed)'. It does not name an alternative tool or state a when-not-to-use condition, but the leak scenario plus the 'needs no confirmation' note makes the intended context unambiguous.

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