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

The description adds important non-obvious behavior beyond the annotations: the upload link expires at expiresAt, cannot be re-fetched, and a fresh one requires calling this tool again. It also discloses that file IDs become available only after the user completes the browser upload, which is essential for correct agent behavior. This goes well beyond the read/idempotent/destructive hints.

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?

The description is dense but every sentence adds critical operational information: the core action, the asynchronous browser step, the expiry/non-refetch behavior, and the public-URL alternative. It is front-loaded with the main purpose and stays within a compact length.

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 tool that depends on a user-side browser action, the description is complete: it explains the returned link, the uploadId timing, expiry, re-fetch behavior, and when not to use the tool. An output schema exists, so return-value detail is not the description's burden, and the description still names the key returned fields.

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?

The input schema already documents all four parameters with 100% coverage, including the environment enum, workspace ID format, message purpose, and maxFiles default. The description does not add parameter-level detail, but with complete schema coverage the baseline of 3 is appropriate.

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: 'Upload a file from the user's computer' and distinguishes this tool from get_file_upload by explaining the upload-link flow and the later retrieval step. It is unambiguous and clearly not a generic file retrieval or listing operation.

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?

The description explicitly says when to use this tool (files from the user's computer) and gives a concrete alternative: public https:// documents can be passed directly to tools without uploading. It also explains the required sequencing with get_file_upload, telling the agent to surface the link before calling that sibling.

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