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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety and repeatability profile is covered. The description adds only the 'professional' qualifier (work vs personal email), which is useful but thin; no mention of lookup failure behavior or coverage, which matters for an open-world external lookup.

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?

A single well-structured sentence that front-loads the outcome and the required inputs. No waste, though it is minimal rather than information-dense.

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 simple three-param read tool with full annotation coverage and full schema coverage, the description is adequate. It falls short on differentiating from the several sibling email tools, which is the main context an agent actually needs 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 description coverage is 100%, so all three parameters (domain, first_name, last_name) are already documented in the schema with examples. The description restates the same trio without adding format or casing nuance, so 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?

States a specific verb and resource ('Finds a professional email address') and the exact inputs, so purpose is unambiguous. However it never distinguishes itself from close siblings like run_email_enrichment, run_email_validation, or run_linkedin_email, which an agent must choose between.

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?

There is no when-to-use guidance, no exclusions, and no mention of the nearby email siblings that could serve the same query. The agent is left to infer selection entirely.

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