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

Annotations already establish read-only, idempotent, non-destructive behavior, so the bar is lower. The description adds real value by disclosing that each aggregate carries n, coverage, caveat, method, as-of date, and CSV/chart URLs, plus a CC BY 4.0 attribution obligation.

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 with no filler. The lead phrase 'The list in numbers' is slightly cute, but the concrete aggregate list and return metadata follow immediately and are front-loaded.

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 and only one optional parameter, the description is nearly complete: it explains what each aggregate returns and notes licensing requirements. It could still clarify what 'the listed companies' means and when to prefer get_stats_history, but the core call context is present.

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% and the enum slugs are largely self-explanatory. The description does map the five aggregates to the chart topics, but it adds no format or edge-case semantics beyond the schema's 'omit for all five' note.

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 resource (aggregate statistics for the listed companies) and enumerates the five aggregates, which clearly distinguishes it from single-record siblings like get_startup. It does not explain how it differs from get_stats_history, so sibling differentiation is only partial.

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 gives no explicit when-to-use guidance and never names an alternative such as get_stats_history. The only usage-shaped detail, omitting chart to get all five, is already stated in the schema.

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