Parse US Address

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

Annotations already provide readOnlyHint, idempotentHint, destructiveHint. Description adds: 'Read-only with no side effects' and explains failure behavior (error messages for invalid API key or rate limit). This goes beyond annotations and gives the agent complete behavioral context.

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?

Single paragraph but well-structured: purpose, usage, limitations, requirements, failure behavior. Every sentence adds value with no fluff. Information is front-loaded and efficient.

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?

No output schema, so description must cover return values. It lists the structured components but does not explicitly state the output format (e.g., JSON object). However, the list and the failure behavior are sufficient. The tool is simple with one parameter, and the context is well-covered. Minor gap in output format detail.

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?

Schema covers 100% of parameters with description, baseline 3. Description provides additional context: 'Raw address text to parse. Freeform input, abbreviations OK. Example: ...' This adds practical guidance beyond the schema's brief description, justifying a 4.

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 tool's purpose: breaking a freeform US address string into structured components. It lists the specific components (address number, street name, etc.) and distinguishes from sibling tools by stating what it does not do (deliverability confirmation via sthan_verify_address, coordinates via sthan_geocode). This is specific and unambiguous.

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 says 'Use when you have messy or unstructured US address text and need the individual fields.' Also clarifies when not to use it (for deliverability or geocoding) and points to siblings. Provides prerequisites (API key) and side effects (rate limits). Comprehensive guidance.

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