list_districts

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

With no annotations provided, the description takes on the transparency burden. It discloses the critical edge case that level=2 returns empty results and explains why, which is exactly the kind of behavioral context needed beyond the basic list operation.

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 sentences, front-loaded with the primary action, followed by a necessary caveat. No filler or repetition of schema-level details.

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 simple nature and full schema coverage, the description covers the essential usage context, including the level-dependent behavior. It is appropriately complete for an agent to select and invoke the tool correctly.

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 already has 100% parameter coverage, describing both level and province_code. The description adds value by tying level=3 to default and explicitly noting the empty response for level=2, which is not stated in the schema itself. This enriches the schema information without redundancy.

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 opens with 'List districts (Quận/Huyện) within a province', which is a specific verb+resource+scope. It clearly distinguishes from sibling tools like list_wards and list_provinces by naming the district level and explaining its dependence on the schema level.

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?

It explicitly states 'Only meaningful for level=3 (pre-2025 3-tier schema, default)' and 'With level=2 the response is empty because the district level was abolished on 2025-07-01', providing clear when-to-use and when-not-to-use guidance, including the reason.

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