Create custom field

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

Annotations already indicate this is a mutating, non-idempotent operation, so the description does not need to restate that. It adds a useful API requirement: option-based data types require the options array. It does not disclose side effects such as persistence, irreversible creation, or permission requirements, but this is acceptable given the annotation coverage.

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 two sentences with no filler. The primary action is front-loaded, and the only additional sentence states a conditional requirement that directly affects successful invocation.

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?

The description, combined with the schema and annotations, is sufficient for an agent to make a basic valid call: provide name, dataType, and options when needed. However, it does not describe the return value, any lifecycle implications, or the meaning of position/placeholder fields, and there is no output schema to fill that gap.

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 describes most parameters, with 71% coverage. The description adds meaningful semantic value by enumerating exactly which data types are option-based (SINGLE_OPTIONS, MULTIPLE_OPTIONS, RADIO, CHECKBOX), which is not derivable from the raw enum alone. It does not clarify the omitted position and placeholder parameters, but the key non-obvious parameter rule is covered.

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 states a specific verb and resource: 'Create a custom field definition.' Using 'definition' distinguishes this from sibling custom-value tools, and 'Create' clearly separates it from list/get/update/delete custom-field 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 implies its usage by stating it creates a custom field definition and gives a conditional instruction for option-based types. However, it does not explicitly contrast this tool with update, delete, list, or custom-value alternatives, so the usage context is implied rather than fully specified.

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