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

No annotations are supplied, so the description bears the full burden. It does disclose the shape of what comes back (ids plus verification states), which is useful, but says nothing about volume, ordering, pagination, or whether the list is complete or filtered.

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?

A single compact sentence with the key information front-loaded and nothing wasted. The parenthetical "(passportuk)" is mildly redundant given the tool name, which keeps it just below the top mark.

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 zero-parameter list tool with no output schema, the description covers the essential contract by naming the returned fields. It still leaves open whether the list is exhaustive, sorted, or paginated, which an agent needs to plan a follow-up call to passportuk_get_fact.

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?

The tool takes zero parameters, so there is no parameter meaning to add; the description correctly spends no words on inputs. Baseline of 4 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?

The description gives a specific verb ("List") and a specific resource ("fact ids + verification states") scoped to passportuk, so an agent knows precisely what it retrieves. It does not explicitly distinguish itself from the sibling passportuk_get_fact, but the resource it names is unambiguous.

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?

There is no statement of when to use this tool versus passportuk_get_fact or passportuk_changes. The discovery-then-fetch pattern is only inferable from the name and sibling set, not from the description text.

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