Delete custom field

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

Annotations already declare destructiveHint=true, readOnlyHint=false and idempotentHint=false, so the safety profile is partly covered. The description adds real value beyond that by naming the affected surfaces (delivery, audience membership, published data) and the irreversible state, plus the confirm=true gate.

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?

Three short sentences, zero filler, with the destructive impact and the confirm requirement front-loaded where an agent will read them first.

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 destructive single-object delete with full annotations and complete schema coverage, the description supplies the impact warning and confirmation requirement an agent needs. A minor gap is what happens to existing subscriber values on the custom field, though 'irreversible state' gestures at it.

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%, so account, confirm, and custom_field_id are already documented in the schema, including the confirm semantics. The description restates the confirm=true requirement but adds no format or syntax detail beyond the schema, 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 (delete) and resource (custom field), matching the sibling family of list/create/update_custom_field. It also hints at the blast radius (delivery, audience membership, published data). It does not explicitly contrast itself with update_custom_field or bulk_create_custom_fields, but the action is unambiguous.

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 a precondition ('Requires confirm=true') and a warning about side effects, which implies caution is needed, but never states when to use this versus alternatives such as update_custom_field for non-destructive edits. Usage context is implied rather than spelled out.

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