upload_file

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

With no annotations, the description carries the full behavioral burden, and it discloses only one nuance: the element may be a file input or a chooser trigger. It says nothing about permissions required, whether the upload is synchronous with the call, visible side effects (dialog or navigation), or whether existing input state is replaced.

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 no filler. The dual-target clarification is useful, though the description is too brief to fully earn the top mark given the tool's 4 parameters and absence of annotations.

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 browser-automation tool with no annotations and no output schema, the definition is minimally adequate: it conveys the action and the target types. It omits what uid refers to, whether the call blocks until upload completes, and any return behavior, which matters when nothing else documents them.

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 75%: pageId and includeSnapshot are documented in-schema, filePaths notes that paths are local to the machine running Chrome, but uid has no description anywhere. The description adds no parameter meaning beyond the schema, so the baseline of 3 for high schema coverage applies, with uid left ambiguous.

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) and resource (file) and clarifies the two target types: a file input or an element that opens a chooser. This is enough to distinguish it from sibling actions like click or fill. It stops short of naming an alternative sibling to route against, so it is clear but not maximally differentiated.

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 when-to-use guidance, no prerequisites, and no mention of alternatives such as click or fill for interacting with the same element. The only hint is that the target may be either a file input or a chooser-opening element, which is targeting guidance rather than usage guidance.

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