Email Disposable

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

Annotations already indicate readOnlyHint=true, openWorldHint=true, idempotentHint=true, destructiveHint=false. Description adds return fields {disposable, domain, provider}, consistent with read-only behavior. No contradiction.

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?

Description is compact: purpose, examples, use-case, companion tools, rate limits, and return structure in three sentences. No fluff, front-loaded with essential info.

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 tool's simplicity (1 param, output schema exists, annotations cover safety), the description fully covers what the agent needs: purpose, when to use, return fields, and rate limits. Complete.

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?

Single parameter email is fully described in schema (100% coverage). Description adds example formats ('user@tempmail.com', 'test@guerrillamail.com'), which is helpful but not critical. Baseline 3, plus 1 for extra context.

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 uses specific verb 'Check if email address uses a known disposable/temporary provider' and lists examples (Guerrilla Mail, Temp Mail, Mailinator). It clearly distinguishes from sibling tools like threat_intel, email_mx, and domain_report by stating their different use cases.

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?

Explicitly states when to use ('input validation to detect throwaway signups') and when not ('for domain reputation use threat_intel'), and mentions companion tools. Also provides rate limits (Free: 30/hr, Pro: 500/hr), aiding selection.

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