vapi_import_phone_number

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

With no annotations provided, the description must disclose behavioral traits but only states a generic action. It fails to mention side effects (e.g., does it overwrite?), required permissions, or whether the operation is reversible. The brevity offers no transparency beyond the bare action.

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?

The description is very short at one sentence, which is concise but at the expense of essential information. It under-specifies the tool's behavior and parameters, making it insufficient for practical use.

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?

Given the complexity of four required parameters with no schema descriptions, no output schema, and no annotations, the description is woefully incomplete. It does not explain what the import entails, what the return value is, or any constraints, leaving the agent without enough information to invoke the tool correctly.

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?

The input schema defines four required parameters (number, provider, providerId, providerToken) with no descriptions. The tool description adds no information about their meaning or expected format, which is critical given 0% schema description coverage.

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?

The description clearly states the tool's purpose as importing a phone number to Vapi, using a specific verb and resource. However, it does not distinguish from the sibling tool 'vapi_buy_phone_number', which also involves obtaining a phone number, leaving ambiguity about when to use each.

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?

The description provides no guidance on when to use this tool versus alternatives, nor does it mention any prerequisites or context for importing a phone number. This leaves the agent without direction for selection.

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