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

With no annotations provided, the description carries the burden. It discloses the read-only nature ('Returns all companies...') and details the output fields, which is transparent. It does not warn about potentially large result sets for depth 2 (though the schema does), nor does it explicitly declare itself read-only, so it falls short of fully comprehensive behavioral disclosure.

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 three concise sentences that front-load the core purpose, then describe the return contents and use cases. Every sentence contributes meaning without redundancy.

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 no output schema and no annotations, the description compensates by specifying return fields and the domain (UK companies, shared directors). It covers the main aspects an agent needs: what it does, what it returns, and when to use it. The only gap is a lack of explicit warnings about result size at larger depths, but the schema addresses that.

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 adds context linking 'depth' to 'up to the specified depth' and 'shared directors' to 'shared board members', but these are already conveyed in the schema. No additional parameter-level meaning is provided 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?

The description clearly states the verb 'Map' and the resource 'corporate network connected to a UK company via shared directors', distinguishing it from sibling tools like get_directors or get_company. It also specifies the output contents (company name, number, status, shared directors), making the tool's function unmistakable.

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 provides explicit use cases ('useful for identifying corporate group structures, related party relationships, and director interlocks') which guides when to apply this tool. However, it does not explicitly name alternative tools for different scenarios or state when not to use it, so it lacks the exclusionary guidance typical of a 5.

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