fetch_url_with_browser

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

With no annotations, the description reveals it uses a browser (Playwright) which implies resource-intensive behavior and ability to handle JavaScript. However, it does not disclose potential downsides like slower performance or memory usage.

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, efficient sentence that clearly communicates the tool's purpose and usage context with no wasted words.

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 simplicity of the tool (1 parameter, no output schema, no annotations), the description is mostly complete. It could mention return format or error cases, but overall it sufficiently informs agent decision-making.

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 only parameter (url) has schema description coverage of 100%, so the description adds no extra meaning beyond the schema. 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 it uses Playwright browser to fetch web content, specifically for restricted sites like those with Cloudflare or CAPTCHA. It effectively distinguishes from sibling tools that likely use simpler methods.

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?

It explicitly says '适用于有访问限制的网站' (suitable for access-restricted sites) and gives examples, providing clear context for when to use this tool. It does not explicitly mention when not to use it, but the guidance is strong.

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