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

Annotations already provide readOnlyHint, destructiveHint false, idempotentHint true, and openWorldHint true, covering safety and idempotency. The description adds that the tool covers all companies registered under the Companies Act, which is useful but does not significantly expand beyond the annotations. No contradictions.

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 concise (two sentences) with no wasted words. It front-loads the key action and scope, making it easy for an agent to parse quickly.

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 the rich annotations (readOnlyHint, destructiveHint, idempotentHint, openWorldHint) and the presence of an output schema, the description provides sufficient context: it clarifies the registry scope (UK Companies House), the search parameter, and the returned fields. No gaps remain.

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 the baseline is 3. The description mentions sample searches in the schema's parameter description (e.g., 'Barclays', 'Tesco') and briefly lists returned fields, but adds only marginal value beyond the schema itself.

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 it searches the UK Companies House registry by name and lists the specific fields returned (company number, name, type, status, etc.). It distinguishes itself from the sibling tool business.ukcompany.details, which likely provides details for a specific company.

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 implies usage for searching by company name and hints at the scope (UK Companies House). It does not explicitly state when not to use or mention alternatives like business.ukcompany.details, but the context is clear enough for an agent to infer proper usage.

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