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

With no annotations, the description carries the burden and does well: it discloses that the tool is unauthenticated ('Open to everyone; no key needed'), that counts are planner estimates via fast reads rather than exact tallies, and that parse completeness is measured over the last 30 publication days. It omits any statement about rate limits or caching, which is a minor gap.

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?

The return-shape listing is front-loaded and well formatted, and the usage paragraph reads cleanly. It loses a point for mild redundancy, restating that counts are estimates in both the return listing ('not exact tallies') and the closing sentence ('counts are estimates (fast reads), not exact tallies').

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?

There is no output schema, yet the description enumerates every returned field with meaning and format (events_approx, companies_approx, coverage {from, to} as YYYY-MM-DD, parse_completeness_last_30d as a share). For a zero-parameter metadata tool, nothing an agent needs in order to call or interpret it is missing.

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, which sets the baseline at 4. The description reinforces this ('Takes no arguments'), removing any ambiguity, but adds nothing further because there is nothing further to add.

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 names a specific resource (the BORME dataset behind this server) and a specific deliverable (coverage and freshness report). It is clearly distinct from the sibling search/list tools, which operate on records rather than dataset-level metadata.

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?

It gives concrete invocation context: call this before running searches to answer 'how much data is there?', 'how fresh is it?' and 'can I trust date filters for period X?'. It does not name a sibling alternative for those questions (none of the listed tools appear to overlap), so there is nothing to exclude, but the routing is implicit rather than spelled out as a one-liner rule.

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