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

Annotations only declare destructiveHint=true; the description adds the details that matter: deletion is permanent, deleting a pool leaves its numbers intact, affected teams fall back to their own caller ID, and in-use caller IDs are rejected. This is exactly the 'what gets destroyed / what happens to dependents' context the annotation cannot carry.

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?

A single dense sentence with the destructive scope front-loaded and the confirm-first rule attached. Every clause carries meaning, though the stacked parentheticals make it slightly harder to parse at a glance.

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?

Two required parameters, full schema coverage, no output schema, and the description covers both deletion modes, side effects on numbers and teams, and the blocking precondition. Nothing an agent needs before calling it 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 description coverage is 100% and the enum is declared in the schema, so both parameters are already documented. The description restates the id source (get_numbers) but adds no format or value-syntax detail beyond 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 (permanently delete) and two concrete resources (number pool or caller ID), and enumerates them explicitly. An agent can distinguish this from delete_setup_item, manage_number, and delete_team 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 clear operating context: confirm with the user first, and the precondition that a caller ID still used by a rep, team, or AI agent cannot be deleted. It also points to get_numbers as the id source. It stops short of routing the agent to an alternative tool when deletion is blocked (e.g., manage_number to unassign first), so it isn't a full when/when-not/alternative statement.

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