parse_phone_number

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

No annotations present, so description carries full burden. Only states it parses and validates, but lacks details on side effects, error behavior, validation outcomes, or auth requirements. Output schema exists but not referenced.

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?

Four sentences with front-loaded purpose. Parameter listed separately. No unnecessary words. Could be more efficient if parameter detail moved to schema.

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?

Despite having output schema, description lacks detail on validation outcomes, supported country codes, and input format variations. Incomplete for a robust parsing 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?

Input schema has 0% description coverage. Description adds example format '+441234567890', clarifying expected input. However, does not specify allowed variations (spaces, dashes) or error handling for invalid numbers.

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?

Clearly states verb 'parse and validate' and resource 'international phone numbers'. Specifies extracted fields (country code, national number). However, phrase 'Supports major country codes' is vague and could be more precise.

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?

Provides basic guidance: 'Use this to extract country code, national number, and validate formatting.' Does not mention when to avoid or compare to alternative tools. No prerequisites stated.

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