download_file

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

Annotations are absent, so the description carries full responsibility for behavioral disclosure. It only mentions 'control browser download' and that it returns a result string. There is no mention of potential side effects (e.g., overwriting existing files), whether the download is blocking, or how the browser handles popups or redirects. This is a significant transparency gap for a browser automation tool.

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 appropriately concise with a clear structure (args and returns in a docstring format). However, it is underwhelming because it omits essential behavioral and usage details, making it feel like an under-specified stub rather than a well-crafted minimal description.

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?

Given the absence of annotations and an output schema, the description should provide enough context for safe and correct invocation. It fails to explain what the return string actually contains, how errors are surfaced, or whether the download completes before returning. The parameter list is bare, leaving the tool incomplete for an agent to use without guessing.

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 0%, meaning the input schema provides no additional meaning beyond parameter names. The description merely lists the parameters (url, path, rename) without explaining formats, constraints, or edge cases (e.g., what 'rename' expects – a full filename or just a base name). This does not compensate for the schema's lack of detail.

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 '控制浏览器下载文件到指定路径' (control browser to download file to specified path), which is a specific verb+resource action. It distinguishes itself from the sibling tool 'upload_file' by being the inverse operation. However, it lacks detail about what types of files or URLs are supported, preventing a perfect score.

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 like 'get' or 'run_js'. No prerequisites are mentioned (e.g., needing to connect or open a browser first via 'connect_or_open_browser'). The description simply states the action without any contextual or exclusionary information.

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