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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is covered. The description usefully adds the required OAuth scope, which annotations do not convey, but it says nothing about side effects that matter most here — e.g., whether values referencing this definition are orphaned or cascade-deleted, or whether the delete is recoverable.

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?

Two short sentences, no filler, and the core action is front-loaded ahead of the prerequisite. Every clause carries information the agent needs.

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 is a simple one-parameter delete with annotations covering destructiveness and no output schema to explain, so minimal text suffices. Still, the highest-risk unknown for this specific resource — the fate of dependent custom field values — is left unaddressed.

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?

A single parameter with 100% schema description coverage, so the schema already documents 'id'. The phrase 'by ID' restates the schema without adding format, lookup, or constraint detail, matching the baseline of 3 when the schema does the heavy lifting.

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 (delete) and a precise resource (custom field definition, by ID), which distinguishes it from delete_custom_field_value and the many other delete_* siblings. It stops short of explicitly contrasting with sibling tools such as update_custom_field_definition or delete_custom_field_value.

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?

Provides one concrete prerequisite — the custom_fields:write scope — which tells the agent whether the call can succeed. It offers no when-to-use/when-not guidance and never names an alternative (e.g., update_custom_field_definition as a non-destructive option), so selection is largely implied by the tool name.

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