browser_file_upload

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

The description adds no behavioral context beyond the annotations. While annotations indicate destructiveHint=true and readOnlyHint=false, the description does not explain the implications of uploading files, such as triggering file selection dialogs or potential overwrites. It also omits the cancellation behavior mentioned in the schema.

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 concise sentence that directly communicates the core functionality. It is front-loaded and contains no unnecessary words, making it highly efficient.

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?

Despite the tool's simplicity, the description lacks essential context. It does not explain return behavior, interaction with the page, or prerequisites. The cancellation behavior is only documented in the schema, not the description, leaving the overall picture incomplete for an 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 input schema already provides a complete description of the 'paths' parameter, including that omitting it cancels the file chooser. The tool description repeats no parameter details and adds no extra semantics. Given the high schema coverage, 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 clearly states the tool's function: 'Upload one or multiple files'. It includes a specific verb and resource, making the purpose evident. However, it does not distinguish itself from sibling tools, though no sibling appears to offer the same upload functionality.

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?

There is no guidance on when to use this tool versus alternatives, nor any mention of prerequisites such as needing a file input element on the page. The description only states what it does, not how to use it effectively.

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