create_custom_field

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

Annotations indicate non-readonly, non-destructive, non-idempotent, open-world. Description adds no behavioral context: no mention of side effects, duplicate handling, permissions, or lifecycle. The description relies entirely on annotations without elaboration.

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?

Single sentence that is efficient and front-loaded. However, it may be too brief given the tool's complexity; but conciseness is valued and no wasted words.

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?

With 8 parameters, no output schema, and a complex domain (custom fields for entities), a single sentence is insufficient. Missing context on how the field integrates with entities, typical usage patterns, or constraints beyond the schema. The description does not fully equip an agent to 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?

Schema has 100% coverage with descriptions for all 8 parameters. The description adds no extra meaning beyond what the schema already provides. Baseline 3 is appropriate as the description does not compensate for any gaps but also does not mislead.

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?

Description clearly states the verb 'Create' and resource 'custom field for extending entity data', distinguishing it from other create tools that handle different entities. However, it does not explicitly contrast with update_custom_field or list_custom_fields, which are siblings.

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 on when to use this tool versus alternatives. The description provides no context for when to create a custom field, prerequisites, or when not to use it. Minimal information leaves the agent to infer from the tool name alone.

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