upload

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

No annotations are provided, so the description carries the full behavioral burden and it discloses almost nothing: it doesn't say whether the change/input events fire, whether the element must already exist, what happens if paths are invalid, or that it mutates page state. Only the implicit fact that this is a write to the page is conveyed.

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 efficient sentence with the target and the input source front-loaded; nothing wasted. It is arguably too terse, but that gap is captured under other dimensions rather than penalized here.

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 5-parameter browser-automation mutation with no annotations and no output schema, the description is far too thin; it never explains the page/tab targeting model, selector defaults, or failure behavior. An agent can guess the call shape from the schema but not the operational context.

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%, so ref, tab, paths, selector and request_timeout are already documented in the schema. The description only reinforces the 'local paths' meaning of the required parameter and adds nothing about selector resolution or tab scoping.

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: 'Set files on a file input' from 'local paths', which is meaningfully distinct from the fill/type siblings that handle text entry. It doesn't explicitly name the sibling it replaces, but the 'file input' target makes the distinction inferable.

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?

No guidance on when to use this instead of fill or fill_form, and no preconditions stated (e.g. that the target element must be an <input type=file>, or that a snapshot/ref should be taken first). The agent must infer usage entirely from the name and schema.

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