vapi-mcp-server

vapi_update_tool

Update an existing Vapi tool by providing its ID and new configuration data to modify its properties.

Instructions

Update an existing Vapi tool

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "id": "<id>",
      "data": "<data>"
    },
    "name": "vapi_update_tool"
  }
}

Input Schema

Name	Required	Description	Default
`id`	Yes
`data`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jun 21, 2026

TDQS

C2.7/5.0

Behavior2/5

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

No annotations are provided, so the description must disclose behavioral traits. It only says 'Update', which implies mutation, but does not specify whether updates are partial or full replacement, idempotency, required permissions, or side effects.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single sentence with no extraneous words, putting the core purpose upfront. However, it may be too terse at the expense of necessary detail.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness1/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has nested objects, no output schema, and no annotations, the description is severely lacking. It does not explain return values, successful status, error conditions, or constraints on the data object, making it inadequate for effective use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has two parameters (id and data) with 0% schema description coverage. The description does not explain the purpose of either parameter, leaving the agent to infer that id identifies the tool and data contains fields to update, which is insufficient.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states 'Update an existing Vapi tool', which specifies the action (update) and the resource (existing Vapi tool). This distinguishes it from sibling tools like vapi_create_tool, vapi_get_tool, and vapi_delete_tool.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives like vapi_create_tool or when updates are appropriate. There is no mention of prerequisites, context, or exclusions.

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