list_custom_fields

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

No annotations are provided, so the description carries the behavioral disclosure burden. It clearly identifies the operation as read-only listing, describes the response contents, and adds useful scope-related context about task responses. It does not mention auth or pagination, but those are not strongly implied by this simple one-parameter list 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 compact and front-loaded with the core action and resource. Every sentence adds value: the first states the purpose, the second details the return shape, and the third connects the tool to usage in other operations. No filler or redundancy.

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?

For a tool with one required parameter and no output schema, the description is complete enough: it names the returned fields, explains scoping behavior, and gives downstream usage context. There are no hidden nested objects or enums to document, and the operation is simple enough that the absence of pagination or error details is not a significant 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 input schema already covers the only parameter, workspace_id, with a description and 100% coverage. The tool description merely references 'a workspace' without adding new meaning about the parameter's format, constraints, or relationship to other resources, so the baseline score of 3 applies.

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 uses a specific verb ('List') with a clear resource ('all custom fields defined in a workspace') and enumerates the exact returned attributes. This distinguishes it from sibling list tools like list_statuses and list_labels by naming the unique resource type.

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 gives concrete usage guidance by telling the agent to use field IDs when setting custom_fields in create_task or update_task. It does not explicitly state when not to use the tool, but there is no competing custom-field sibling tool, so the guidance is sufficient.

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