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

With no annotations, the description carries the full burden. It discloses the row structure (one row per licence, domain, or premises keyed by stable identifiers), the data source (daily public register files), the exclusion of personal licences, the credit cost, and the filter combination semantics. It does not mention pagination defaults or output ordering, but these are minor gaps given the detailed behavioral disclosure.

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 information-dense but well-organized, front-loading the core purpose and then adding details about record types, data source, exclusions, and filtering. Every sentence adds value, and it avoids fluff, though it is somewhat long. The structure is logical and readable.

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 21 parameters, no output schema, and no annotations, the description is moderately complete. It clearly describes the data content and row semantics, and it mentions cost and filter behavior. However, it lacks explanations of parameter semantics, pagination limits (though the schema provides defaults), and does not describe the exact structure of the response or any examples. This is a gap for an agent to fully understand how to construct complex queries.

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 has 21 parameters with zero descriptions, so the description must compensate. While it mentions that filters combine with AND and q searches all text fields, it does not explain individual parameters like 'status', 'activities', 'outward_code', 'local_authority', or the date fields. Parameter names are somewhat self-explanatory but ambiguous ones like 'status' and 'is_active' remain unclear, and there is no guidance on expected values or formats.

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 returns licensed gambling operators in Great Britain, covering licences, domains, and premises, with specific details like status, activities, dates, and trading names. It explicitly distinguishes this from personal licences and other data sources, and the verb 'query' plus the resource 'uk_gambling_operators' is unambiguous.

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 provides some usage context by noting it covers only operating licences and excludes personal licences, and it explains filter behavior ('Filters combine with AND; q searches all text fields'). However, it does not explicitly state when to use this tool versus sibling tools like query_uk_sanctions or query_uk_companies, nor does it mention any prerequisites or alternative data sources beyond the daily register.

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