list_tools

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

With no annotations, the description carries full burden for behavioral transparency, but it only states 'Lists all Vapi tools.' It does not disclose whether the operation is read-only, if there are any side effects, rate limits, or pagination behavior. This is insufficient for a comprehensive understanding.

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 a single sentence that concisely states the tool's function with no extraneous words. It is appropriately front-loaded and efficient.

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 simple listing tool with no parameters and no output schema, the description is adequate but minimal. It could benefit from mentioning return format, pagination, or ordering, which are common for list operations. Still, it is complete enough for basic understanding.

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 has zero parameters, and schema description coverage is 100%. Since there are no parameters to explain, the description does not need to add parameter semantics. Baseline for 0 parameters is 4, and no deficiency is noted.

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 'Lists all Vapi tools' clearly specifies the verb (lists) and the resource (Vapi tools). It distinguishes from sibling tools like list_assistants and list_phone_numbers by naming the specific resource type.

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?

No explicit guidance on when to use this tool versus alternatives is provided. While the name and description imply it is the sole tool for listing tools, there is no mention of context, restrictions, or alternatives, leaving room for ambiguity.

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