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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world scope, so the safety profile is covered. The description adds the meaningful constraint that only places containing doulas are returned, which is not derivable from the annotations. It says nothing about pagination, result ordering, or the shape of the geographic hierarchy.

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?

A single front-loaded sentence with zero filler. Every word contributes: verb, three resource levels, and the scoping condition.

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?

For a zero-parameter, read-only, idempotent tool this is nearly sufficient, but with no output schema the description bears the burden of describing returns. It names the entity types returned yet leaves open whether the three levels are nested hierarchically or returned as a flat list, and whether names or identifiers come back.

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 there is no parameter semantics to document. Baseline of 4 applies; the description correctly implies the tool is unfiltered and returns its full set.

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?

States a specific verb and resource: 'List countries, regions and cities that have doulas.' The scope qualifier ('that have doulas') makes the returned set unambiguous. It doesn't explicitly contrast with siblings like list_categories or search_listings, but the geographic-places framing makes it distinguishable.

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?

No when-to-use guidance and no named alternatives. The phrase 'that have doulas' hints at the content scope but says nothing about when an agent should call this versus list_categories, search_listings, or get_stats. Usage must be inferred entirely.

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