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

With no annotations, the description carries the burden and does disclose two non-obvious traits: the returned aggregates (location and episode counts) and that country names are Polish, which affects downstream matching. It omits ordering, pagination, and completeness guarantees, but for a zero-parameter read this is solid 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?

Two short sentences, front-loaded with the resource and scope, then the payload/locale detail. No filler and nothing repeated from structured fields.

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?

No output schema exists, so the description sensibly summarizes what comes back (location and episode counts, Polish names). An agent has enough to call it and interpret results; only ordering and cardinality are unspecified.

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 takes zero parameters, so the baseline is 4; the empty schema means there is nothing extra for the description to explain. The description correctly signals the tool is unfiltered.

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?

Specific verb+resource plus scope: 'All countries Robert Makłowicz visited' tells the agent exactly what set is returned, and 'with location and episode counts' names the payload attributes. The note that names are in Polish further distinguishes it from the sibling location tools.

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?

Usage is only implied — the agent can infer it is the enumeration tool versus search_locations or get_location for lookup, but the description never says when to prefer it or that it takes no filters. No explicit alternatives or exclusions are given.

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