mcp-spotify-free

by vakandi

Overview Schema Source Related Servers Discussions Admin

Python

Local

Set Volume

set_volume

Adjust the playback volume of a Spotify Connect device from 0 to 100, targeting the active device or a named one.

Instructions

Set the volume of a device (0-100).

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": {
      "level": "<level>"
    },
    "name": "set_volume"
  }
}

Input Schema

Name	Required	Description	Default
`level`	Yes	0 = mute, 100 = max.
`device`	No	device name ("" = active device).

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.1.1Oct 23, 2026

TDQS

B3.1/5.0

Behavior2/5

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

No annotations are provided, so the description carries the full behavioral burden and mostly fails: it does not say whether the change persists, whether level 0 doubles as mute, what happens if the named device is missing/offline, or what errors may surface. Only the mutation intent is conveyed.

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

Conciseness5/5

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

A single short sentence with the operation and range front-loaded and zero filler. Nothing in it is wasted, though the terseness leaves gaps addressed in other dimensions.

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

Completeness3/5

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

An output schema exists, so return values need not be explained, and the two-parameter surface is simple. Still, with no annotations a real description should mention device/connection prerequisites and failure modes for a mutation targeting external hardware.

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

Parameters3/5

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

Schema description coverage is 100% — the schema already documents `level` (0 = mute, 100 = max) and `device` ("" = active device). The description's '(0-100)' restates the schema rather than adding new meaning, so the baseline 3 applies.

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

Purpose4/5

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

States a specific verb and resource (set the volume of a device) plus the accepted range, so an agent knows exactly what the call does. It does not name or differentiate against any sibling, though none of the listed siblings overlap with volume control.

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?

There is no guidance on when to use this versus alternatives, no prerequisites (e.g. whether an active/host device or Chromecast session is required), and no statement about behavior when no device is specified beyond the schema's default.

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