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

With no annotations provided, the description carries the full burden. It discloses that nothing is purchased or paid, no quote is guaranteed, and it's free, which pertains to the underlying submit_enquiry. It also states what the tool returns (who receives details, consent wording, confirmation method). While it doesn't explicitly say 'this tool is read-only', the wording 'Read first' and 'States plainly' strongly imply a non-mutating, informational operation.

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 'Read first' and then explains what it does. It's slightly wordy but each sentence adds value: the first explains the scope, the second clarifies the non-transactional nature, and the third lists the returned content. No fluff, but it could be tightened slightly.

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 tool with no parameters and no output schema, the description is complete: it explains what it does, what it returns, and the context of the underlying action. It doesn't describe formatting or additional edge cases, but none are required for this simple descriptive tool. It fully equips an agent to call it correctly.

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 tool has zero parameters, so the schema trivially covers 100%. The baseline for 0 params is 4, and the description adds no parameter-related details because none are needed. It correctly focuses on behavior and return content instead.

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 clearly states the tool's purpose: it explains what submit_enquiry does on Engine Rebuild Cost, and it distinguishes itself from siblings by being a read-first description tool rather than the action or fields tool. The verb 'states plainly' is specific and the resource (submit_enquiry behavior) is explicit.

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?

'Read first' gives a clear directive to use this before submit_enquiry, implying it's the explanatory precursor. It doesn't explicitly name alternatives or exclusions, but the context of siblings and the tool's descriptive nature makes the usage obvious. A small gap is not naming enquiry_fields as the source for field-level details.

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