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

Annotations already declare destructiveHint=true and readOnlyHint=false, yet the description adds substantial context beyond them: irreversibility, the DID-routing precondition, the default detach-vs-delete behavior for member trunks, the refusal condition when a member still carries DIDs, and the two-step confirmation_token flow. This is exactly the extra behavioral detail annotations cannot convey.

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?

Five tight sentences, front-loaded with the destructive warning and identity of the resource; each remaining sentence carries a distinct constraint or default with no filler.

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?

With no output schema needed (return value is described as a confirmation message on success), the description covers everything required to invoke safely: target identification, precondition checks, default member-trunk behavior, and the confirmation-token round trip.

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%, so the baseline is 3, but the description adds meaning the schema lacks — notably that delete_member_trunks=true is refused if any member trunk still carries DIDs, and that confirmation_token is a preview-then-confirm safety gate.

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 precise verb+resource ('Delete ... Voice IN Trunk Groups by id') and scopes it to the authenticated customer's own groups, which cleanly separates it from siblings like delete_trunk, delete_sms_trunk, and delete_capacity_group.

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 explicit preconditions and when-not conditions: a group with DIDs routed to it cannot be deleted until those DIDs are re-routed, and member trunks are only detached by default. It does not name a sibling alternative explicitly, but the gating conditions are unambiguous.

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