UK company filing history

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

With no annotations, the description carries the full burden and does disclose key behavior: the item fields returned, that results are paged, that category filtering is supported, and that failures return an error object with a code field. It omits result ordering, auth/rate-limit requirements, and what a missing company number yields, which keeps it below a 5.

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?

Four compact sentences, front-loaded with purpose, then returns, filtering, paging and error shape. No filler, though the return-field enumeration is dense enough that a reader must parse it mid-sentence.

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?

No output schema exists, and the description compensates by enumerating the returned item fields and the error object shape, plus paging behavior. An agent has enough to call it correctly; only auth, ordering and empty-result semantics are missing.

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%, so start_index, items_per_page and company_number are fully documented in the schema. The description only restates the category filter, adding no semantics beyond the schema — the baseline 3 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?

States a specific verb and resource ('List the filing history of one UK company by its number'), which is clearly distinct in kind from company_search, company_profile and company_officers. It does not explicitly name the siblings, but the resource ('filing history') is a natural discriminator.

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?

Usage is only implied by the resource name — an agent can infer it should call this when it needs filings rather than profile data. No explicit when/when-not guidance or named alternatives (e.g. 'use company_profile for registered-office and status details') are provided.

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