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

With no annotations, the description carries the full load and does it well: it discloses the auth requirement (Authorization: Bearer), a rate/quota constraint ('metered per key per day'), and graceful unauthenticated behavior ('without a key the answer says how to get one'). It stops short of describing pagination termination or how the caller knows it has reached the last page.

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 tight sentences, front-loaded with the resource and paging, followed by auth/quota and no-key fallback. Every sentence earns its place, though 'the answer says how to get one' is slightly loose phrasing.

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?

With no annotations, no output schema, and 0% schema description coverage, the description does a fair amount of work (scope, auth, quota, fallback) but leaves two gaps an agent would want closed: how pagination ends and what a page's payload/provenance actually contains.

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 0%, so the description must compensate. '200 a page' usefully conveys the intended pageSize chunk (schema allows 1-200) and 'in pages' implies the page parameter, but defaults, page numbering (1-based), and the relationship between page and pageSize are left unstated.

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 resource ('every entity of Roofing Quotes UK register') and mode ('in pages, 200 a page, with provenance'), which is enough to distinguish a full-register dump from the filtering siblings (entities_search, entities_in). It does not explicitly name those siblings, so the differentiation is inferred rather than stated.

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 implied rather than stated: 'every entity' signals bulk export as opposed to the filtered lookups offered by entities_search/entity_lookup, and the auth prerequisite is given. There is no explicit when-to-use/when-not statement or named alternative, so guidance stays at the implied level.

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