Upload a file

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

Beyond annotations (which already declare it non-read-only and non-destructive), the description discloses non-obvious behavior: files are converted when not in the listed formats, the returned assetId is the payload to reuse, and assets are retained only 14 days. That retention/conversion detail is genuinely additive.

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?

A single front-loaded sentence with zero redundancy; the action, accepted inputs, and returned value are all packed in without 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 one-parameter upload tool with no output schema, the description states the return value (assetId) and retention window, which is what an agent needs. It stops short of noting upload size limits or auth prerequisites, but is largely complete.

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% and the single filePath parameter is fully documented with accepted formats in the schema itself. The description echoes the format categories but adds no syntax, path-format, or size-limit detail beyond what the schema provides, so baseline 3 is appropriate.

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 (upload), the accepted resource types (local image, reference video/audio), and the outcome (assetId for later generations). It is clearly distinguishable from siblings like library_save_job and library_list, though it doesn't explicitly name them.

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 phrase 'for reuse in later generations' implies the use case, but there is no explicit when-to-use vs when-not guidance or reference to the alternative tools (e.g. axcel_library_save_job). Usage is inferable but not stated.

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