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

Annotations already declare destructive=true and readOnly=false, and the description adds meaningful constraints: base64 uploads, 1 MB per file, 100 files and 50 MB per account. It does not clarify delete permanence, authentication requirements beyond ownership, or what listing returns, leaving some behavioral gaps.

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 sentences with no wasted wording. The action list and key scope distinction are front-loaded, followed by the most operationally important constraints.

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 multi-action tool with only 17% schema description coverage and no output schema, the description is incomplete. It covers upload limits and bucket scope but omits per-action parameter requirements, return behavior, and delete semantics that an agent would need to invoke each action correctly.

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 only 17%, so the description must compensate. It explains that uploads use base64 content and implies the project must be owned, which clarifies contentBase64 and projectId. However, action, fileId, name, and mimeType remain largely undocumented, and there is no mapping of parameters to specific actions.

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 names specific verbs (list, upload, download, delete) and the resource (private files on a Data project the account owns). It also distinguishes itself from a public Supabase Storage bucket, but the generic tool name 'files' and the multi-action scope keep it from being maximally clear.

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?

It gives useful scope context (existing private bucket, not public) and upload limits, but does not explain when to choose this tool over siblings or when each action is appropriate. There are no explicit exclusions or alternatives beyond the bucket distinction.

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