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

Goes well beyond the annotations: it discloses per-destination size ceilings (5 GB for /attachments, 100 MB for drives), the one-hour link lifetime, that the file only lands once the upload finishes, and that nothing is billed. It does not say what happens on a partial or expired upload, nor describe the return payload shape, so a small behavioral gap remains against a non-read-only, non-idempotent tool.

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?

Purpose is front-loaded and essentially every clause carries operational information, but it is delivered as one dense run-on paragraph mixing limits, two upload channels, and the drive follow-up call, which costs some scannability.

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?

There is no output schema, and the description compensates by explaining the two returned handles (put_url for HTTP PUT, page_url for the human drop-box) and how each is used. Combined with the file-size rules and upload_done follow-up, an agent has everything needed to invoke it 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 coverage is 100%, so the baseline is 3, but the description adds real meaning the schema cannot: it ties `path` prefixes to concrete size limits and to whether upload_done must follow, and explains that the size parameter is validated against those limits before any bytes move.

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?

Names a specific verb+resource (get a link to upload a file) and immediately distinguishes itself from the sibling add_attachment by stating the base64/32 MB limitation it exists to bypass. It also scopes the supported destinations, so an agent knows exactly what class of operation this is.

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 explicit routing conditions: use this instead of add_attachment when the file is too large or must not pass through the conversation; use the shell PUT when a shell exists, otherwise hand the person page_url; and for connected-drive paths, call upload_done afterward. It also names the failure condition (any other path is refused).

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