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

With no annotations, the description carries the burden, and it does disclose the auth/billing model ('caller's OpenAny gateway credentials', 'charges and authorization are determined by the gateway') — useful context an agent would not otherwise have. It is silent on the failure mode (no email found), whether a negative result still costs credits, and what the response looks like.

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?

Three short sentences, purpose first, then auth/billing caveats. Efficient overall, though the first line is an unpunctuated fragment with a line break mid-description, which slightly hurts readability.

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 2-parameter lookup with no output schema, the description covers what it does and the billing/auth model, but omits the outcome contract (what a hit vs. miss returns) and any note about latency or credit consumption per call. Adequate but leaves gaps an agent would want closed before calling in a paid pipeline.

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% and both parameters are well documented there, including the domain-omission fallback to current employers in seniority order. The description only restates the id/domain relationship at a high level, adding no syntax or format detail beyond the schema. Baseline 3 applies.

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?

First sentence names a specific verb and resource ('resolves a work email address'), the unit of work ('a single person'), and the scope qualifier ('on a specific domain'), which lines up with the id+domain schema. It does not differentiate from the many sibling email-finding tools (hunter_get_v2_email_finder, treg_post_call_dropleads_people_search, etc.), though the 'by person id' qualifier in the title partially does that job.

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?

Usage is only implied: the caller has a CompanyEnrich person id and wants an email. Nothing says when to prefer this over a domain-based or name-based email finder, or what to do when the person has no known employer. The domain-vs-omit behavior is documented, but only in the schema, not as routing guidance.

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