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

Adds meaningful behavior beyond the annotations: it states the call is approval-gated, that it 'unlocks the command center', and critically that it 'does not claim customer coverage' because routes remain pending until independently verified — clarifying how far the destructive mutation actually reaches. It does not say what authority object is required, whether the choice can be changed afterward, or what happens to a previously saved route.

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?

Front-loaded with the APPROVAL-GATED signal and kept to three dense sentences with no filler. The middle clause about unlocking the command center while not claiming coverage is a little tangled but each sentence does work.

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?

Output schema exists, so return-value explanation is rightly omitted, and the description covers the important gating and verification caveats for a destructive, idempotent mutation. It is somewhat thin on prerequisite/authority requirements and on which parameters pair with which choice, which is a notable gap at 17% schema coverage.

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?

With 6 parameters and only 17% schema description coverage, the description must carry the load; it partly does by explaining the semantics of the 'testing' enum value and noting forwarding is optional. The other required parameters (business_id, activation_session_id, idempotency_key, authority) get no explanation, and the description does not mention source_phone even though the schema requires it for forwarding or both.

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?

Names a specific effect — saving one of four enumerated customer-route choices (forwarding, published_number, both, testing) — and qualifies it as approval-gated. The verb 'save' and the enumerated choices make the operation identifiable, though the phrasing 'save forwarding, published_number, both, or testing' requires the reader to already know these are route modes.

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?

Explicitly gates invocation on 'after private-test proof is complete' and explains what 'testing' means versus connecting a route, which is real when-to-use guidance. It gives no guidance on when to pick each route mode, no prerequisites for the approval step, and does not reference any sibling tool for previewing or approving the route.

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