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

Goes well beyond the annotations: it discloses that the returned link is short-lived, that the USER must open it in a browser and drop files (human-in-the-loop), and that a second call is required to obtain stored URLs. It also exposes the API key requirement for the alternative path. Annotations (readOnlyHint=false, destructiveHint=false, idempotentHint=false) are consistent with a link-generating, non-destructive operation.

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-loads the purpose and the routing decision before the mechanical detail, and every sentence carries decision-relevant content. The embedded curl block makes it longer than typical, but it is high-value guidance rather than 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 tool with no output schema and a single optional parameter, the description supplies everything an agent needs: what the link is, who consumes it, its lifetime, and the exact next call to make. No meaningful gap remains for correct invocation.

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?

Only one optional parameter ('note') and the schema already documents it at 100% coverage, so the baseline of 3 applies. The description adds no extra meaning about the note parameter (e.g. that it is only shown to the agent, not the user).

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 concrete verb+resource (create an upload link for the user's own files) and immediately scopes it to files that exist only inside the conversation. It cleanly separates itself from siblings upload_file and list_uploaded_files by describing the browser-drop workflow rather than a direct upload.

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?

Explicitly says when to use it ('when you cannot make HTTP requests or the file only exists as an attachment in the chat') and when not to ('IF YOU CAN RUN SHELL COMMANDS, skip this and upload directly'), including the alternative command. It also names the required follow-up call (list_uploaded_files) and the downstream tools that consume the result.

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