upload_file

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions that the tool returns 'the file path to use in subsequent API calls,' which adds useful context about the output. However, it lacks details on potential errors, file size limits, authentication needs, or rate limits, leaving gaps in behavioral understanding for a mutation 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?

The description is appropriately sized and front-loaded, consisting of two concise sentences that directly state the tool's purpose and outcome. Every sentence earns its place by providing essential information without redundancy or unnecessary details.

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?

Given the tool has one parameter with full schema coverage and no output schema, the description is moderately complete. It explains the purpose and return value, but as a mutation tool with no annotations, it could benefit from more details on behavioral aspects like error handling or prerequisites, making it adequate but with clear gaps.

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 schema description coverage is 100%, with the parameter 'file_path' fully documented in the schema as 'Local file path to upload (video, audio, or image).' The description does not add any additional meaning beyond this, such as format specifics or constraints, so it meets the baseline score of 3 where the schema handles the parameter documentation.

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 clearly states the specific action ('Upload a local file') and the resource ('to Magic Hour'), distinguishing it from sibling tools which focus on deletion, detection, swapping, or status retrieval. It explicitly mentions the purpose 'for use in other tools,' which adds context beyond a basic upload 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 provides clear context for when to use this tool ('for use in other tools'), implying it's a prerequisite step for subsequent operations. However, it does not explicitly state when not to use it or name alternatives, such as whether other tools might handle file uploads differently or if there are limitations on file types beyond what's hinted in the schema.

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