list_custom_fields

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

Annotations fully cover safety (readOnlyHint, destructiveHint) and idempotency, so behavioral transparency is adequate. The description adds no additional behavioral details beyond what annotations already provide.

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 only three words, which is under-specified rather than concise. It omits crucial information about behavior and parameters, failing to earn 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?

Despite having an output schema and simple parameters, the description is too minimal. It does not state that the output is a list, or clarify default ordering, pagination limits, or typical use cases.

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 description coverage is 0%, and the description does not mention any parameters. The parameters 'page', 'ordering', and 'page_size' are left unexplained, offering no help to the agent beyond their names.

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 'List custom fields.' clearly states the verb (List) and the resource (custom fields), making the basic purpose unambiguous. However, it does not differentiate from sibling tools like 'list_correspondents' or 'get_custom_field'.

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?

No guidance is provided on when to use this tool over alternatives such as 'get_custom_field' (for a single field) or other list tools. The usage context is entirely implied.

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