extract_data_from_url

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the core fetch-and-extract behavior and does not mention limitations such as JavaScript rendering, selector failure handling, page-load behavior, rate limits, or whether the operation is safe and read-only.

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, tight, front-loaded sentence with no wasted words. It communicates the core action and differentiator efficiently, though its brevity means it omits useful parameter and behavioral details that the low schema coverage cannot supply.

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?

With no output schema and three inputs, the description is under-specified for safely invoking this tool. An agent is left without information about the return shape, error behavior, or how this tool relates to the sibling tools, which is a notable gap for a network-fetching and DOM-extraction tool.

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 only 33%, and the main description adds little beyond the schema's structural requirements. It does not explain how selectors map to returned values, what 'name' represents, how 'multiple' changes results, or how 'max_value_length' truncates data, leaving the agent to infer this from the schema alone.

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 action ('Fetches a web page and extracts precise data'), a clear resource ('web page'), and a specific method ('using CSS selectors'). It differentiates from sibling tools like extract_page_text and inspect_page_structure by emphasizing precise, selector-based extraction.

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 implies when to use the tool: when precise, selector-based data extraction from a page's DOM is needed. However, it does not explicitly state when to prefer this over siblings like extract_page_text or discover_selectors, nor does it mention any exclusions or conditions.

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