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

Annotations already flag destructiveHint=true and idempotentHint=true, so the description's job is blast-radius detail — and it delivers exactly that: the list object is destroyed, contacts survive, membership is lost, and the action is irreversible. That "what gets destroyed vs. preserved" distinction is the single most decision-relevant fact and it is not derivable from 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?

Three short sentences: action, consequence, safety instruction — ordered from most to least critical with zero filler. Every sentence carries distinct information.

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 one-parameter delete with full annotation coverage and no output schema, the description covers purpose, effect, irreversibility, and the required confirmation step. Nothing an agent needs in order to invoke it safely is missing.

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 coverage is 100% and the sole parameter already documents type, bounds, and provenance ("from directiq_list_lists"). The description adds only the phrase "by ID," which is redundant with the schema, so baseline 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?

States a specific verb and resource ("Permanently delete a contact list by ID") and the second sentence disambiguates it from the contact-level siblings (directiq_delete_contact, directiq_remove_contact_from_list) by clarifying that contacts are retained. An agent can pick the right tool without opening any schema.

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?

Gives an explicit workflow precondition: "confirm with the user first" before this irreversible action. It implies the alternative (removing membership rather than the list) via the retained-contacts note, but never names a sibling tool or states when deletion is the wrong choice.

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