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

Annotations already declare the tool as read-only, idempotent, and non-destructive. The description adds context on data source ('DMV's own directory') and coverage ('all 187 field offices'). No contradictions; however, it could mention rate limits or authentication, but for a read-only tool, current detail is adequate.

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 concise (about 5 sentences), front-loaded with the core purpose, and every sentence adds value. No fluff or redundancy.

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?

Although there is no output schema, the description explains the return type (address, opening hours, coordinates, services) and coverage (187 offices). This is sufficient for a query tool with well-documented parameters.

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 coverage is 100% with all parameters described. The description goes beyond schema by listing example services ('behind-the-wheel retest, duplicate title, etc.'), which provides helpful hints for the service parameter.

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 verb 'find' and resource 'California DMV field offices', and lists the information returned: address, opening hours, coordinates, and services. It distinguishes from siblings by noting that wait times are not available and pointing to alternative tools.

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 provides example queries ('DMV office in Sacramento', 'which California DMV near San Jose does driving tests') and explicitly states when not to use it: for live wait times, California publishes none, and suggests siblings nc_dmv_wait_times and or_dmv_wait_times.

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