get_ip_postal

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It adds useful context: the default behavior when ip is None (returns current postal code) and the return type (Postal or ZIP code). However, it omits details like error handling, rate limits, or data source, which are important for a lookup tool.

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 front-loaded with the core purpose in the first sentence, followed by structured Args and Returns sections. Every sentence earns its place by providing essential information without redundancy, making it highly efficient and well-organized.

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 the tool's low complexity, one parameter, and an output schema (which handles return values), the description is nearly complete. It covers purpose, parameter semantics, and return type. However, it could improve by mentioning data accuracy or limitations, slightly reducing completeness for a lookup 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 schema has 0% description coverage, so the description must compensate fully. It does so by explaining the single parameter 'ip' in detail: its purpose ('IP address to lookup'), optionality ('If None'), and effect ('returns current postal code'). This adds significant meaning beyond the bare 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 specific action ('Get just the postal code') and resource ('for an IP address'), distinguishing it from siblings like get_ip_city, get_ip_country, and get_ip_info by focusing exclusively on postal/ZIP code retrieval. The verb 'Get' is precise and the scope is well-defined.

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?

The description implicitly provides usage guidance by specifying 'just the postal code,' suggesting this tool should be used when only postal information is needed versus broader tools like get_ip_info. However, it lacks explicit when-not-to-use statements or named alternatives, such as comparing to get_ip_location for more comprehensive data.

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