Get cities

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

Annotations declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, which already cover the safety profile. The description adds 'reference list' which suggests a static, non-exhaustive enumeration, but it doesn't disclose potential quirks like pagination, sorting, or whether the list is authoritative. For such a simple tool, this is acceptable, but it doesn't go beyond the annotations.

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, concise sentence that gets straight to the point. It is front-loaded, with no wasted words or redundancy. Every part of the sentence earns its place.

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 list tool with no output schema, the description gives the essential information: it returns a reference list of cities. It could be more explicit about the return format or usage context, but given the simplicity, the description is largely complete. Minor gaps are acceptable.

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. The description's phrase 'reference list of cities' correctly implies no inputs are required. There is no parameter documentation needed because there are none.

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 'Reference list of cities' clearly identifies the resource (cities) and the nature of the tool (a reference list). Combined with the title 'Get cities', the purpose is unambiguous and distinguishable from sibling tools, none of which relate to cities. A slight improvement would be an explicit 'Returns...' phrasing, but it's clear enough.

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 guidance on when to use this tool or when to prefer an alternative. The description is a single statement with no context about typical use cases, prerequisites, or exclusions. This leaves the agent without explicit direction on tool selection.

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