Get custom field values

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is fully covered. The description adds only that the result may cover all fields or one, and says nothing about error behavior, missing fields, or result shape.

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?

A single short, front-loaded fragment with no filler, though it is a sentence fragment rather than a complete statement of action.

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 simple read tool with three fully documented parameters the definition is nearly adequate, but with no output schema it should describe what the returned custom field values look like and how it relates to the definitions-listing sibling.

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% for all three parameters, so the schema already documents entity, entityId and fieldName. The description restates fieldName's effect without adding format or edge-case detail, making 3 the correct baseline.

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 names the resource (custom field values) and constrains it to a single entity, with an optional narrowing to one field. It lacks an explicit verb and never names the sibling list_custom_field_definitions, so the values-vs-definitions distinction is only implicit.

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?

There is no statement of when to call this tool versus list_custom_field_definitions or any other sibling, and no prerequisites. The only conditional given ('a single one with fieldName') describes a parameter mode rather than when the tool itself applies.

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