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

With no annotations, the description carries the full burden. It does disclose substantial logic: containment semantics, that partial or no period overlap counts as a mismatch, that version/basis/unit must be equal after normalization, and that taxonomy containment is transitive. It does not state what the call returns (a verdict? per-dimension results?), what happens when a dimension is absent on one side, or whether the taxonomy is required for geography/population comparisons.

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 scope statement is front-loaded well, but the body is a single dense run-on enumerating three rule groups, and the text is visibly truncated mid-word ('Des'), signaling an incomplete definition. The information is useful but the packaging is cramped.

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 nested three-parameter comparison tool with no output schema and no annotations, the definition explains the comparison semantics thoroughly but leaves two material gaps: the shape of the result and the behavior when taxonomy or a dimension is omitted. The truncation further suggests the definition is unfinished.

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 100%, so the baseline is 3; the description earns above that by explaining that the taxonomy encodes containment facts used as the caller's own hierarchy for geography and population, and by spelling out the matching rule applied to each parameter group. It still does not address taxonomy absence or default behavior.

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 opens with a specific verb and resource: 'Check that evidence covers the scope of the claim it is used for,' then enumerates the six dimensions compared (geography, population, period, version, basis, unit). An agent can tell precisely what this tool validates without opening the schema.

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 detailed per-dimension mismatch rules (containment for geography/population, containment for period, equality after normalization for version/basis/unit), which tells an agent what inputs will pass. However, there is no explicit statement of when to call this versus other checks, no prerequisites, and no exclusions.

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