Check UK visa sponsor licence

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 results include a confidence grade, that generic-word matches are unreliable, and that a 'none' result does not rule out sponsorship and should prompt checking the registered legal entity. This is substantial behavioral context beyond a basic lookup, though it does not cover aspects like rate limits or authentication.

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 three sentences and immediately states the action, then adds caveats about confidence and interpretation. Every sentence adds value, and the most important information (the lookup) comes first. No redundancy.

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 output schema and no annotations, the description covers the essential aspects: what it checks, what result to expect (confidence grade), and how to interpret negative results. It does not specify the exact response format, but the description gives enough for an agent to decide whether to call the tool and how to interpret its output. Some detail on the confidence grade scale might be missing, but overall it is quite 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%, so both parameters (company and skilledWorkerOnly) are already documented in the schema. The description adds no additional parameter-level detail; it only implies that company names may collide but does not clarify formatting or validation beyond what the schema states.

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 states a specific action: 'Look up whether a company holds a UK Skilled Worker sponsor licence.' It names the resource (company) and the licence type, and the wording clearly distinguishes it from the unrelated siblings like screen_posting or application_history.

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 does not explicitly specify when to use this tool versus alternatives, nor does it state exclusions. The purpose implies the use case (checking sponsorship), but there is no direct guidance on when not to use it or what to use instead. However, the description does provide interpretive guidance for results, which indirectly helps the agent decide next steps.

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