Zeltor Music Tools
com.zeltorlabs/music-toolszeltorlabs.comstreamable-httpv1.1.0Scanned
Check if two songs mix (Camelot key, BPM), read shared song DNA reports, tempo and nightcore math.
5 tools: 5 change things.
- Reads private data · 0
- Reads text others write · 0
- Can send data out · 0
- 1 finding
Tools listed without sign-in. Remote posture
Anlyon alternative
5 of these tools change something. Run those as governed actions.
Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.
Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.
Import an OpenAPI spec →Tools
Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.
5 tools
Changes things 5Claude Code: ask
camelotGives the Camelot wheel code for a key and the three other keys that mix cleanly with it (one step either way with the same letter, and the relative major or minor).No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it Gives the Camelot wheel code for a key and the three other keys that mix cleanly with it (one step either way with the same letter, and the relative major or minor).
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
check_mixDecides whether two songs will mix well, from their keys and BPMs, using the Camelot wheel and DJ tempo limits (about 3% sounds natural, up to about 16% is usable, half and double …No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it Decides whether two songs will mix well, from their keys and BPMs, using the Camelot wheel and DJ tempo limits (about 3% sounds natural, up to about 16% is usable, half and double time count). Returns a verdict, the tempo change in percent and the target BPM for track B, the smallest key shift in semitones if the keys clash, and a link to make the matched audio.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
speed_pitchFor a nightcore (faster and higher) or slowed (slower and lower) version: the pitch change in semitones for a speed, the new BPM if given, and typical settings.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it For a nightcore (faster and higher) or slowed (slower and lower) version: the pitch change in semitones for a speed, the new BPM if given, and typical settings. Defaults: nightcore 1.25x, slowed 0.80x.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
tempo_changePercent change and playback rate to go from one BPM to another, how noticeable it will sound, the pitch change if it is not time-stretched, and the half and double time of the targ…No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it Percent change and playback rate to go from one BPM to another, how noticeable it will sound, the pitch change if it is not time-stretched, and the half and double time of the target.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
transposeMoves a key up or down by semitones and gives the new key name and Camelot code, with a note on how natural the shift will sound.1 finding
Why it is in this group
- The description's first verb is "move": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
The server marks "transpose" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
What this check looks forMatched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The description's first verb is "move": a word for a change.
Description, as the server wrote it Moves a key up or down by semitones and gives the new key name and Camelot code, with a note on how natural the shift will sound.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.
Exfil surface
Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.
No private-data, untrusted-input, outbound path in this server alone: no tool is tagged private-data or untrusted-input or outbound.
- Reads private data0
- Reads files, mail, messages, databases, secrets, calendars or repositories.
- Reads text others write0
- Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
- Can send data out0
- Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.
Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.
Remote posture
What anyone on the internet sees at the remote endpoint: an anonymous initialize and tools/list, and the public OAuth metadata.
Looked at Oct 31, 2026, 23:19 UTC, unchanged since Oct 31, 2026. No credentials were sent and no tool was called. What is looked at.
- Reachable
- yes
- HTTP status of an anonymous initialize
- 200
- tools/list served without credentials
- yes
- Tools that change things, listed without credentials
- 5
- Protocol version
- 2025-06-18
- WWW-Authenticate on 401
- not observed
- resource_metadata in WWW-Authenticate
- not observed
- RFC 9728 protected resource metadata
- not observed
- Authorization servers
- not observed
- Legacy HTTP+SSE transport
- no
- Dynamic client registration
- not observed
- Client ID metadata documents
- not observed
- WarnThe whole server
The endpoint served tools/list without credentials, and the list has 5 tools that change things (5 write). Whether a call also works without credentials was not tested: tools are never called.
What this check looks forMatched text
https://zeltorlabs.com/mcp: tools/list returned 6 tools to an anonymous client, including check_mix (write), camelot (write), tempo_change (write), speed_pitch (write), transpose (write)
Findings
Matches of fixed checks, with the text they matched.
- Warntranspose
The server marks "transpose" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
What this check looks forMatched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The description's first verb is "move": a word for a change.
History
Changes to its tool definitions and to its remote endpoint, newest first.
No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.
Install
Pinned to version 1.1.0. Values in angle brackets are yours to fill in.
claude mcp add --transport http music-tools https://zeltorlabs.com/mcpclaude mcp add --transport http music-tools https://zeltorlabs.com/mcpRun in a terminal.
Claude Code permissions
Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.
{
"permissions": {
"allow": [],
"ask": [
"mcp__music-tools__check_mix",
"mcp__music-tools__camelot",
"mcp__music-tools__tempo_change",
"mcp__music-tools__speed_pitch",
"mcp__music-tools__transpose"
],
"deny": []
}
}Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as music-tools. Review it before you use it.
Pin
Keep the decision: fail CI when the tools change, follow every change, or show a badge.
Pin in CI
Fail a build when the tools you reviewed are not the tools the server serves today.
curl -s "https://anlyon.dev/api/v1/servers/com.zeltorlabs/music-tools/verify?hash=416cbad114b004262979facbba2bcccaf5943f8aeefa316d2df0bac29f141e1d" | jq -e '.changed == false'Pinned hash 416cbad114b0, from Oct 31, 2026, 22:18 UTC.
Watch
Get told when its tools change: a new tool, a new description, a new class.
https://anlyon.dev/servers/com.zeltorlabs/music-tools/changes.xmlAn Atom feed. Works in any feed reader or Slack's RSS app.
Badge
[](https://anlyon.dev/servers/com.zeltorlabs/music-tools)Source: MCP Registry. Synced Oct 31, 2026, 23:17 UTC.