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

Annotations already mark readOnlyHint=true, so the safe read-only behavior is covered. The description adds useful non-obvious context: the pricing tier, per-call cost, plan inclusion, and 'cross-catalog synthesis' behavior. It does not discuss return format or rate limits, but the annotation lowers the burden.

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 description is compact, front-loaded with the core purpose, and every clause earns its place: corpus scope, sequencing advice, and pricing. The pricing information is integrated without obscuring the functional purpose.

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 parameterless overview, the description adequately states the salient outputs and the recommended reading order. The schema handles the one optional parameter, and without an output schema the description gives enough expectation of what the call returns.

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 schema covers the single optional context parameter with 100% description coverage, including intent and how it is used. The tool description adds no parameter-specific semantics, so the baseline of 3 is appropriate.

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 concrete resource, 'the Insights root', and specifies measurable outputs: number of companies profiled, number of quarters, and top investment dimensions. This clearly separates it from the more granular sibling tools without ambiguity.

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 explicitly says 'Read this FIRST' and frames the tool as the prerequisite before drawing conclusions from any single company, giving strong contextual guidance. It does not name sibling alternatives for deeper insights, so exclusion guidance is only implicit.

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