get_registered_office_history

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

Annotations already establish readOnlyHint, idempotentHint, and destructiveHint=false. The description adds useful behavioral context beyond that: results are ordered newest first, addresses are included only 'where the register has them', and there are two upstream requests. It stops short of describing error/rate-limit behavior, but the annotations lower the bar.

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?

Three short sentences, all substantive: the first defines the exact scope and ordering, the second gives an analytical trigger, and the third states request cost. There is no filler, and the core purpose is front-loaded.

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?

Given one required parameter, a rich schema description, an output schema, and annotations covering read-only/idempotent/non-destructive behavior, the description supplies everything needed to call the tool correctly: purpose, result ordering, data completeness caveat, and upstream cost.

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 coverage is 100%, and the schema description already explains company_number with format examples, tolerated input variations, and a fallback to search_companies. The tool description itself does not add parameter-level meaning, so the baseline of 3 is appropriate.

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 and resource: 'Get a company's current registered office and every recorded change to it, newest first, with old and new addresses where the register has them.' It clearly defines scope, ordering, and what data is included, and it is easily distinguished from siblings like get_company_profile by the historical dimension.

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 gives clear context on when the result is analytically important ('Frequent moves, or a move shortly before insolvency, are worth pointing out') and warns about cost ('Two upstream requests'). It does not explicitly name alternatives or exclusions, but no sibling offers this same history scope, so the guidance is sufficient.

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