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

Annotations already establish this is a non-destructive, non-open-world read, and the description usefully adds what the read actually returns — benchmark values, industry/geography/period/sample-size metadata, source name/URL/excerpt/comments, and a citation URL. That return-content detail is meaningful since there is no output schema, though limits such as availability or missing-data behavior are not covered.

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?

A single dense sentence with the scope constraint ('one kpi_id per call') front-loaded and no filler. It is well packed, though the trailing 'Each response includes a citation URL' partially repeats the source URL already listed.

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?

With no output schema, the description carries the burden of describing the return payload and does so credibly, covering both data and provenance. For a one-parameter read tool with full annotation coverage, an agent has enough to invoke it correctly, though guidance on what to do when no benchmark exists is absent.

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% and the schema already declares 'Single value only — no arrays or wildcards', which the description's 'one kpi_id per call' merely restates. The description adds no new parameter semantics beyond the schema.

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+resource: retrieves benchmark data for a single KPI, and enumerates what comes back (benchmark values, descriptive metadata, source attribution). It does not explicitly contrast itself with get_kpi or search_kpis, so the sibling differentiation is only implied by the 'one kpi_id per call' scope.

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 'one kpi_id per call' phrasing implies this is a single-item lookup rather than a search, which is useful, but the description never states when to use this instead of get_kpi or search_kpis. That routing information exists only in the schema's reference to search_kpis, not in the description.

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