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

With no annotations, the description carries the full burden. It usefully discloses that nothing is bought, ordered, or paid; no quote is guaranteed; the service is free; and it returns who receives the details, consent wording, and confirmation process. The only weakness is that the description shifts between describing submit_enquiry and describing this tool, slightly blurring whether these consequences apply to the call itself or to the enquiry being described.

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 compact and front-loaded with the 'Read first' instruction. Every sentence contributes something meaningful: scope, key caveats, and returned content. There is no filler or repetition.

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 zero-parameter informational tool with no output schema, the description adequately explains what the tool returns and sets user expectations about the enquiry process. It could be slightly more explicit that calling this describe tool itself does not submit an enquiry, but overall it is sufficient for an agent to select and invoke 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 accepts zero parameters and the schema fully documents this with an empty properties object. There is nothing for the description to add about parameter meaning, so the baseline of 4 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?

The description clearly states the tool's function: it explains what submit_enquiry does on the Malta Tax Refund Calculator. It distinguishes this from purchase or guaranteed-quote actions, and the title reinforces the scope. This makes it easy to tell apart from siblings like calculator_describe and submit_enquiry.

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 opening 'Read first' explicitly signals when to use this tool: before engaging with submit_enquiry. It does not explicitly contrast with alternatives like calculator_describe or enquiry_fields, but the context and purpose are clear enough for an agent to infer appropriate use.

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