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

No annotations are present, so the description carries the full behavioral burden. It usefully discloses that the tool refuses with do_not_answer when data is drifted or unverified and never guesses, but it does not explain what happens for an invalid or missing fact_id, nor what a successful response contains.

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?

Two short sentences with the core action front-loaded and no wasted wording. The refusal behavior is stated compactly and reinforces the tool's reliability posture.

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 simple single-parameter retrieval tool, the purpose and refusal behavior are covered, but the lack of output schema means the description should say more about what a successful fact response looks like. The undefined fact_id remains a notable gap.

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 description coverage is 0%, so the description must compensate for the undocumented fact_id parameter. It does not explain what a fact_id is, where to obtain one, or its expected format, leaving the sole parameter largely opaque beyond its name.

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 verb and resource: 'Get one verified fact from the votinguk pack.' It is clear enough to distinguish this tool from the many sibling fact packs by its votinguk domain, though it does not explicitly differentiate itself from votinguk_list_facts or votinguk_changes.

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 by the description—retrieve one fact by its ID—but there is no explicit guidance on when to use this versus listing facts or checking changes. The refusal condition is useful behavioral context, not a when-to-use rule.

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