get_city_info

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

No annotations provided, but description discloses return fields (name, code, country, coordinates, timezone, population/popularity), indicates read-only intent (no mutation mentioned), and provides use case examples. Could be improved by explicitly stating read-only.

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?

Description is front-loaded with trigger, then action, returns, use cases, and sibling differentiation. Every sentence adds value with no fluff.

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 simple lookup tool with 3 optional parameters and no output schema, the description covers all essential context: when to use, what it returns, example inputs, and differentiation from related tools.

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?

All parameters have schema descriptions (100% coverage), but description adds value by specifying default return fields when `_fields` is omitted, giving example values for `city_code` ('LON') and `country_code` ('BG'), and clarifying the aviation context.

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?

Description clearly states the tool looks up cities by code or country in an aviation database, with verb 'look up', resource 'cities in the world cities database', and distinguishes from sibling 'search_airport_code' which converts city name to code.

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?

Explicitly states when to use: aviation city code/grouping queries or listing cities of a country in aviation context; when not to use: general geography; provides alternative sibling tool for name-to-code conversion.

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