get_upload_url

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

With no annotations, the description must carry behavioral context. It discloses the authentication requirement and that the result is a presigned URL for direct R2 upload, but it omits important traits such as URL expiration, upload method (PUT), and whether a successful response returns the URL in a JSON envelope.

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 a single front-loaded sentence, with no filler. Every clause contributes: the operation, the destination, and the auth prerequisite.

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?

The tool is simple and has complete parameter documentation, but there is no output schema and the description does not state the expected response shape, expiration behavior, or how the returned URL should be used. The core action is clear, yet an agent may lack enough detail to handle the result 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 input schema already fully documents both file_name and content_type. The description adds no parameter-level detail beyond the schema, keeping this at the baseline.

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 uses a specific verb ('Get') and resource ('a presigned URL to upload a photo directly to R2'), making the tool's purpose unmistakable. This clearly distinguishes it from the sibling tools, none of which offer direct upload URL generation.

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 conveys clear usage context by noting the upload is direct to R2 and that an API token is required. It doesn't name exclusions or alternative tools, but no sibling tool offers the same capability, so the guidance is adequate.

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