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

Annotations already declare readOnlyHint and openWorldHint. The description adds behavioral context by specifying what kind of historical data is returned (names, address changes, license history), giving the agent a clearer expectation of the tool's output. This goes beyond the annotations, though it doesn't cover edge cases like empty results or data completeness.

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 two sentences long and front-loaded with the core purpose. The second sentence about due diligence adds relevant context without fluff. Every word earns its place, making it highly concise and well-structured.

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?

Given the tool's simplicity (one param, no output schema) and existing annotations, the description covers the essential use case and data scope. However, it could mention potential caveats like incomplete history or the completeness of the data, especially since openWorldHint is true. Minor gap in full completeness.

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 already fully documents the 'ico' parameter with its format ('Czech IČO (7-8 digits)'). The description does not add additional parameter semantics beyond the schema, so a baseline score 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 uses a specific verb 'Get' with a clear resource 'historical record of a company' and enumerates specific data types (previous names, registered address changes, trade license history). This distinguishes it from sibling tools like lookup_by_ico or get_statutaries, making its purpose unambiguous.

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 phrase 'Useful for due diligence' provides a use case but does not explicitly compare this tool to alternatives or state when not to use it. It implies usage context without giving clear directives, such as 'use lookup_by_ico for current data'.

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