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

No annotations are supplied, so the description carries the full burden. It usefully discloses the refusal path ('do_not_answer' on drift/unverified, 'never guesses'), which is real behavioral context beyond the schema, but says nothing about the success response shape, freshness metadata, or error surface.

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, zero filler, with the core action front-loaded and the failure behavior second. Nothing would be lost by keeping it exactly as is.

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 one-parameter lookup in a family of many domain packs, the definition covers the action and the refusal semantics but leaves the key gap: how to obtain a fact_id and what a successful result contains. Larger than it looks given the parallel sibling tools that must be distinguished.

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% — the single fact_id parameter is entirely undocumented. The description adds no format, naming convention, or origin for fact_id (e.g., from deposituk_list_facts), so an agent must guess what a valid id looks like.

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: 'Get one verified fact from the deposituk pack.' The singular 'one fact' implicitly contrasts with the sibling deposituk_list_facts, but no sibling is explicitly named, so differentiation is inferential 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?

The description implies usage (fetch an individual fact by id) and warns that drifted or unverified facts refuse, but it never says when to prefer this over deposituk_list_facts or deposituk_changes, nor where a valid fact_id comes from.

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