List custom fields

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the agent knows this is a safe read operation. The description adds only the 'entity type' scoping, which is somewhat redundant with the schema. It does not disclose pagination behavior or other operational details, so the description adds minimal extra context beyond the annotations.

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 a single, concise sentence that is front-loaded. It contains no filler or redundant information, and every word earns its place.

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?

This is a list tool with no output schema and five parameters including pagination and filtering options. The description only states the basic purpose and does not mention pagination, filtering, or the nature of the returned data. Annotations cover the safety profile but not operational completeness, so the description leaves significant gaps.

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 only 20% (only filter_type has a description). The description mentions 'entity type' but does not explain page, limit, order_id, or filter_type beyond what the schema enums provide. With low schema coverage, the description should compensate, but it does not.

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 verb 'List' and the resource 'custom fields' with a scope of 'for an entity type.' It effectively distinguishes this list operation from sibling tools like create, update, delete, and get for custom fields.

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 implies usage when one needs to list custom fields for an entity type, but it does not explicitly state when to use this over alternatives, nor does it mention exclusions or prerequisites. Given the large number of sibling tools, more explicit guidance would be helpful, but the basic use case is clear.

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