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

Beyond the annotations, the description discloses that the enquiry is delivered to the agency's CRM, that this sends personal details to a third party, that usage works without an API key up to a daily per-IP allowance, and that a free key removes the limit. These are meaningful behavioral and privacy traits that are not present in the annotations or schema.

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 front-loaded with purpose and usage, then covers operational and consent constraints in a compact, well-organized way. It is longer than average, but every sentence carries useful information for safe invocation, including the API-key allowance and the privacy warning.

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 side-effecting tool with no output schema, the description is unusually complete: it states when to use it, what will happen after submission, how to get the reference, what data is sent, the API-key/rate-limit context, and the consent requirement. An agent has what it needs to invoke it correctly and safely.

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?

The schema already covers 100% of parameters with descriptions, so the baseline is 3. The description adds only modest value by saying the reference comes from search results and that enquirer contact details are required; it does not add format, validation, or behavior details for individual parameters beyond the schema.

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?

Description names a specific verb and resource: submitting an enquiry (lead) about a specific listing on behalf of a prospective buyer or tenant. It also distinguishes this from generic contact/listing operations by explaining that it is the supported way to reach a listing agency and that direct phone/email details are not exposed by other tools.

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?

It gives an explicit trigger ('once the user has chosen a property and wants the agency to contact them'), an explicit prerequisite (clear intent and consent), and an explicit alternative boundary (other tools do not expose direct contact details). This leaves little ambiguity about when submit_enquiry should be selected.

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