list_custom_fields

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds real value beyond them: a 1-hour cache and the shape of returned field objects (id, name, code, type, enum options). It stops short of describing cache invalidation or pagination behavior.

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?

Four short sentences, front-loaded with what the tool does, then safety, return shape, caching, and the chaining hint. No sentence is redundant.

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 no output schema, the description steps in to describe the returned object fields, and with only one optional parameter and full annotation coverage there is nothing an agent needs to call this correctly that is missing.

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 coverage is 100% with a single, fully documented entity_type parameter including its default, so the schema does the heavy lifting. The description's mention of 'leads, contacts, or companies' merely restates it without adding format or edge-case detail, making the baseline 3 appropriate.

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?

States a specific verb (List) and resource (custom field definitions) and scopes it to the three entity types, which clearly separates it from create_custom_field and from the lead/contact CRUD 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?

Gives concrete downstream guidance: use the returned field IDs in custom_fields_values when calling update_lead or update_contact. It does not state exclusions or when to prefer a sibling, but the intended workflow context is explicit.

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