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

With no annotations provided, the description carries the full behavioral burden. It discloses that the tool serves the entire register ('Served whole'), is free, is a machine mirror of a public register, and is descriptive rather than inferential. This gives the agent a clear model of the tool's scope and side-effect-free nature.

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 dense, front-loaded sentences cover the resource, the full content of the response, the delivery mode, the non-inferential nature, and the relevant sibling tool. Every clause earns its place; there is no filler or repetition.

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 there is no output schema, the description compensates by listing the major content categories a caller should expect: nations, assignments, categories, evidence, URLs, metadata, and provenance sections. It is sufficiently complete for a parameterless retrieval tool, though exact field-level shape is not specified.

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 tool has zero parameters, so the baseline is 4 and the description does not need to explain argument semantics. The description reinforces that no filtering or configuration is possible by emphasizing that the register is served whole.

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 opens with a specific verb and resource ('Retrieve the WEO Bloc Membership Register') and then enumerates exactly what the tool returns: nations, bloc assignments, membership categories, evidence, source URLs, metadata, and provenance. It actively distinguishes itself from get_methodology by stating that category definitions are served there.

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 usage context is clear: this tool serves the whole register and is appropriate for retrieving bloc membership facts. It explicitly routes the user to get_methodology for category definitions and warns that it is 'a descriptive roster, never inference,' which helps the agent avoid using it for analytical or definitional tasks.

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