enrich_email_batch

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 does so thoroughly: billing per item, MX lookup deduplication across domains, the honesty caveat that MX presence does not guarantee a valid mailbox, and the exact return structure including error format. This goes beyond a typical description.

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 well-structured with an intro, an Args section, and a Returns section. Every sentence adds value: the billing note, the honesty note, the dedup note, and the return keys. No wasted words. The most important usage information is front-loaded.

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?

For a batch tool with two parameters and no output schema, the description is complete. It defines parameter ranges, default behavior, return keys, error format, and cost implications. An agent can invoke it correctly without further lookup. The only missing piece (auth, rate limits) is likely handled at a platform level and not required here.

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 the parameters. It does: 'emails: 1–100 email addresses' adds the count constraint, and 'check_mx: When true (default), perform MX DNS lookups (deduped by domain)' adds behavior and default. This is exactly the kind of semantic enrichment the schema lacks.

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 opens with a clear, specific verb+resource: 'Validate up to 100 emails in one call.' It immediately distinguishes this from the single-email enrich_email tool by the batch capability. The purpose is 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 implies when to use this tool (when you have multiple emails) and references enrich_email as the comparable single-item tool ('Same honesty as enrich_email'). It does not explicitly state 'use this instead of enrich_email for batches,' but the batch limit and per-item billing make the usage context clear. No explicit alternatives are named beyond the sibling list, but the context is sufficient.

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