Create Custom Field

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

With no annotations, the description bears the transparency burden. It provides useful behavioral details such as requiring an options array for Dropdown/RadioList/Checkbox fields and pipeline_id for pipeline fields. However, it does not describe side effects, permissions, return values, or error conditions, which are important for a create 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?

The description is concise and front-loaded with the main purpose. The field types list is somewhat redundant with the schema enum but provides a quick reference. Each sentence serves a purpose, and there is minimal fluff.

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 tool has 9 parameters and no output schema or annotations. The description covers the core use case and conditional requirements but omits information about the response format, permissions, or potential errors. While it is adequate for a create operation, it lacks completeness in explaining the tool's full behavior.

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 100%, so the parameters are well-documented. The description adds minimal extra semantics by clarifying the conditional requirements for options and pipeline_id, but this largely duplicates the schema descriptions. No additional insight is given for other parameters like is_required or show_on_report.

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 the tool creates a new custom field definition and specifies the resources (contacts, companies, pipelines). It distinguishes itself from sibling tools like edit_custom_field and delete_custom_field by focusing on the 'new' creation aspect.

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 explicitly says 'Use this to add new fields for contacts, companies, or pipelines,' providing clear context for when to use it. However, it does not explicitly mention alternative tools for editing or deleting custom fields, so it lacks a direct when-not-to-use statement.

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