upload

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 states the action ('upload a file') but doesn't describe critical behavioral traits: whether this requires authentication, what happens on failure, if there are rate limits, file size restrictions, or what 'fal.ai storage' means in terms of persistence/access. The return value mention is helpful but minimal.

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 concise with three sentences that each serve a purpose: stating the action, explaining the parameter, and describing the return. It's front-loaded with the core purpose. Minor improvements could include integrating the parameter explanation more seamlessly, but overall it avoids unnecessary verbosity.

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 complexity of a file upload operation with no annotations, no output schema, and minimal parameter documentation, the description is incomplete. It doesn't cover authentication needs, error handling, file constraints, or what 'Information about the uploaded file' includes beyond 'file_url'. For a mutation tool with zero structured metadata, this leaves significant gaps for the agent.

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 description adds some semantic context for the single parameter ('path: The absolute path to the file to upload'), which is valuable since schema description coverage is 0%. However, it doesn't clarify what constitutes a valid 'absolute path' (local filesystem? URL?), supported file systems, or path format requirements. The baseline is 3 because the schema has only one parameter, but the description doesn't fully compensate for the 0% schema coverage.

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 verb ('upload') and resource ('a file to fal.ai storage'), making the purpose immediately understandable. It distinguishes this from sibling tools like 'generate' or 'search' by focusing on file transfer rather than processing or querying. However, it doesn't specify what types of files are supported or any size limitations that might differentiate it from similar upload tools.

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 no guidance on when to use this tool versus alternatives. There's no mention of prerequisites (like authentication), when not to use it, or how it relates to sibling tools like 'cancel' or 'status' that might be relevant for upload operations. The agent must infer usage context entirely from the tool name and basic description.

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