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

With no annotations, the description carries the responsibility for disclosing behavior. It clearly describes what the analysis returns: compliance score (0-100), risk band, itemised findings with Article citations, and source verification per finding. It does not explicitly state side-effect status, but a gap analysis is inherently a non-mutating evaluation.

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 one sentence, front-loaded with the action and resource, and concisely lists the key return elements without fluff. Every phrase earns its place.

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?

Since there is no output schema, the description's breakdown of return values is essential and well provided. The input schema fully documents parameters. It lacks explicit alternative tool guidance, but for a single-purpose analysis tool the overall description is largely complete.

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% and the schema already explains the answers object and language parameter, including Q1..Q10 format and accepted legacy strings. The tool description only reinforces the 10-question structure and does not add meaning 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?

The description uses a specific verb ('Run') and a specific resource ('full 10-question VAT compliance gap analysis'). It clearly distinguishes this as a comprehensive analysis tool versus the narrower sibling tools like vat_number_check or vat_rate_lookup.

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 description states the tool runs the full 10-question analysis but gives no explicit guidance on when to choose this over alternatives such as vat_registration_check or reverse_charge_certificate. The word 'full' implies comprehensive use, but no when-not conditions or selection criteria are provided.

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