browser_file_upload

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

Annotations already flag this as a non-read-only, destructive action, so the safety profile is covered. But the description adds no extra behavioral context: it doesn't explain file-chooser behavior, what happens when paths are omitted, or what side effects the upload has. This leaves the operational behavior largely opaque.

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 a single focused sentence with no wasted words and is easy to parse. It is appropriately concise, though it borders on under-specification because it carries no context about the file chooser or invocation timing.

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 tool with complete schema coverage and annotations, the definition is minimally viable. However, it misses key operational context: when to call this tool, how the upload target is determined, and how it interacts with the browser's file chooser. The schema hints at cancellation but the overall description leaves 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 already describes paths as absolute file paths and notes that omitting them cancels the file chooser, with 100% description coverage. The description adds no additional parameter meaning beyond the obvious 'files' connection, so a baseline score of 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?

The description states a specific verb and resource: 'Upload one or multiple files.' It clearly identifies the core operation and is distinguishable from sibling tools like browser_drop or browser_fill_form. However, it does not explicitly mention the browser/file-chooser context, which would sharpen the purpose further.

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 gives no guidance on when to use this tool versus alternatives such as browser_drop, nor does it mention the need for a file chooser to be active. There are no exclusions, prerequisites, or contextual triggers provided.

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