list_custom_fields

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

With no annotations, the description carries the full burden. It does disclose the HTTP method (GET /v1/custom_fields) and return structure, implying a read-only operation. However, it omits details like authentication requirements, potential rate limits, or whether empty results are handled, so transparency is adequate but not rich.

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 and well-structured with sections for purpose, API call, and return structure. Each line adds value without redundancy, and the main summary is front-loaded.

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 low complexity (no parameters, no output schema) the description is complete: it defines the tool's purpose, the exact API endpoint, and the return format with field examples. This is sufficient 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?

There are zero parameters and the schema is empty, so the baseline is 4. The description adds no parameter semantics because none exist, but it does explain what the return dict contains, which is more relevant here.

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 '取得商店定義的客戶自訂欄位清單' (get the store's list of custom fields for customers), specifying a concrete verb and resource. It distinguishes itself from sibling tools like list_customers or list_customer_groups by focusing on custom field definitions rather than customer data or groups.

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 explains when to use it: to understand customer data structure or analyze data completeness. It provides clear context but does not explicitly mention when not to use it or name alternative tools, so it falls short of full guidance.

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