list_countries

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

With no annotations provided, the description carries the burden of disclosing behavior. It clearly describes the return content (counts and specific metrics), which is useful. However, it does not mention whether the operation is read-only, potential side effects, rate limits, pagination, or how the returned data is structured beyond field names. The 'list' phrasing implies a safe read, but explicit behavioral context is missing.

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 a single sentence that front-loads the main action ('List countries covered') followed by the specific metrics. It is reasonably concise, though the packed list of technical terms (branches_covered, branch_taxonomy, branch_overview_pages) makes it slightly dense. No unnecessary verbiage is present.

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 that this is a simple no-parameter tool with an output schema present, the description is largely complete. It explains the meaning of key output fields (e.g., branches_covered, branch_taxonomy) that might otherwise be ambiguous. The complexity is low, so the description sufficiently covers the contextual needs for an agent to select and invoke the tool.

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 input schema has no parameters, so the parameter semantics baseline is 4. The description does not need to explain parameters because there are none, and it instead focuses on what the output contains, which adds value 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 tool lists countries and enumerates the specific metrics included (product/insurer/regulation counts, branches_covered, branch_taxonomy, branch_overview_pages). This makes the purpose unambiguous and distinguishes it from sibling tools like list_branches, which focus on branches rather than country-level aggregates.

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?

There is no explicit guidance on when to use this tool versus alternatives such as list_branches or get_branch_overview. The description implies it is for obtaining country-level statistics, but it does not state that it should be used over others or provide any exclusion criteria. As a no-parameter tool, usage is straightforward, but the absence of comparative guidance leaves the agent to infer context.

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