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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the bar is lower. The description adds real value beyond that: the authoritative source, that names/addresses are Korean-only, and that opening hours are NOT included — a genuine limitation that prevents wrong assumptions.

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?

Two dense sentences: the capability and return fields are front-loaded, followed by the usage caveats. Zero filler, every clause earns its place.

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 exists, and the description compensates by listing returned fields (address, phone, 24-hour flag). The only omissions are result limit/pagination behavior and how multiple matches are ranked — minor against an otherwise complete definition for a simple 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?

Schema coverage is 75%, so most parameters are already documented in structured fields. The description adds context for 'region' (district-level, must be Korean) but says nothing about 'sido', 'limit', or the emergency_only flag mechanics beyond the schema's own text. Baseline 3 is appropriate.

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?

States a specific verb+resource (open veterinary clinics in a Korean si/gun/gu district), names the data source (Ministry of the Interior licensing data), and enumerates the returned fields. An agent can tell exactly what this tool yields without opening the schema.

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?

Clear usage context: Korea only, district-level granularity, Korean-language queries. No explicit comparison to siblings (check_toxic_food, find_pet_travel, etc.), but those are clearly different domains, so routing ambiguity is low. Scope exclusions ('no opening hours') are stated, though the alternative for hours lookup isn't given.

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