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

No annotations are provided, so the description carries the full burden and does most of it: it discloses the transport (direct multipart/form-data POST to the gateway), the auth precondition ('works without a token (the upload itself needs one)'), the exact response contents (URL, method, form field name, Authorization header), and the downstream artifact ('uid' usable in a conversion). It stops short of error behavior, size limits, or expiry characteristics, so it is not exhaustive.

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-loaded with the operation and the critical 'no presigned URLs' clarification, then progressively covers response shape, post-upload workflow, the preferred alternative, and auth. Every sentence carries distinct information; nothing is padding.

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?

With no annotations and no output schema, the description must supply the return contract and behavioral context on its own, and it does: response fields, the follow-on file object and its uid, the alternative tool, and the auth caveat. An agent can call this correctly without opening anything else.

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 100% and there is only one parameter, so the baseline is 3. The description restates that the filename is used for the multipart form filename, which duplicates the schema's own definition rather than adding new semantics.

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 specific verb+resource (returns upload instructions for an agent-local file into FileConvert) and immediately corrects the likely false assumption baked into the tool name: 'FileConvert does NOT use presigned upload URLs'. It also differentiates itself from sibling convert_file by naming the alternative path explicitly.

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 an explicit routing rule: 'If your file is reachable over http(s), prefer convert_file(source_url, target_format) which fetches and uploads it for you.' Combined with the note that the upload itself needs a token, an agent knows both when to pick this tool and when not to.

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