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

No annotations are supplied, so the description carries the full disclosure burden, and it adds only a credit cost ('cost: 1 credit'), which is genuinely useful. It says nothing about what a search returns (datasets vs. bulletins vs. series records), pagination, result ranking, or whether the cost is per call or per result, which matters for a metered tool.

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 clauses, front-loaded with the action and the resource, with the cost tucked in a parenthetical. Nothing is wasted, though the brevity is close to under-specification rather than disciplined economy.

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 metered, annotation-free search tool with no output schema, an agent still cannot tell what a result record looks like, how to page through results, or why it should pick this over 'ons_timeseries'. The description is complete enough to attempt a call but not enough to call it correctly the first time.

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 100% ('query' as required string, 'limit' as number 1-50), so the schema already documents both parameters. The description adds no meaning beyond that, but the baseline of 3 applies when the schema does the heavy lifting.

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 ('Search') and names the concrete resource domain ('ONS datasets, bulletins and time series'), so an agent knows this queries UK Office for National Statistics content. It falls short of a 5 because it never distinguishes itself from the sibling 'ons_timeseries', even though it explicitly claims to cover time series, leaving ambiguity about which tool handles series data.

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 guidance on when to use this versus the obvious alternative, 'ons_timeseries', or versus generic search siblings like 'govuk_search' or 'news_search'. Usage is only implied by the word 'Search', and no exclusions, prerequisites, or selection criteria are stated.

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