extract_emails

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

With no annotations providing behavioral context, the description carries the full burden. It discloses that results can be returned inline or saved to a table via save_as, and that errors are included. However, it omits potential side effects like network usage, rate limits, or the meaning of mode/js_render, which limits full transparency.

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 two sentences, extremely concise, and well-structured: it states the purpose, then the output format, then the save option. No extraneous information is present, and the structure is logical.

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?

While the tool's core function is clear, the description fails to provide sufficient context for optional parameters (mode, js_render) and does not elaborate on the output structure (e.g., what 'context' contains). Given the tool's moderate complexity, more detail is needed for full completeness.

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 coverage is 0%, so the description must explain parameters. It only clarifies save_as (storing vs returning) and implicitly urls (list of URLs). It leaves mode (what does 'replace' mean?) and js_render (when and why) unexplained, which is a significant gap given no parameter descriptions exist.

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 scans a list of URLs for email addresses, which is a specific verb-resource combination. It distinguishes itself from sibling tools like extract_phones and extract_social_links by focusing on emails, making the purpose unambiguous.

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 clearly indicates when to use the tool (to extract emails from URLs) and mentions the save_as option for storing results instead of returning them. However, it does not explicitly contrast with alternatives, though the purpose is clear enough.

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