Extract email addresses from text

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

With no annotations provided, the description carries the full burden. It discloses optional deduplication and lowercasing behavior, adding value beyond the schema defaults. However, it does not mention edge cases like invalid formats, no matches, or the return type, which could be relevant for an extraction tool. This is adequate but not rich.

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 sentence with a trailing clause, front-loaded with the core purpose. Every word earns its place—no fluff or redundancy. It is highly concise while conveying essential behavior.

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?

This is a low-complexity tool with no output schema, but the description explains the input and optional processing, making the return (a list of extracted emails) fairly obvious. It is complete enough for the tool's simplicity, though a note about empty results could improve it.

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 100%, so the baseline is 3. The description adds context by framing the text parameter as 'free-form text' and noting optional processing, but it largely mirrors the schema's default descriptions. It does not add significant syntactic or behavioral detail beyond what the schema already provides.

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 verb (extract), the resource (email addresses), and the context (free-form text), which is distinct from sibling tools like verify_email or clean_email_list. It also notes optional deduplication and lowercasing, adding specificity.

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 implies when to use: when you have free-form text with email addresses, such as notes, documents, or signatures. It does not explicitly exclude alternatives, but the context and sibling list make the extraction use case clear. No exclusions are needed for this simple utility.

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