Audiolab

tools.audiolabPublished by audiolab.toolsv0.5.0Updated Oct 30, 2026

Loudness, true-peak and voice-quality analysis of URLs and local files via the hosted AudioLab API.

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Overview

AI-generated overview

Local stdio MCP server that sends audio URLs or local files to the hosted AudioLab API for loudness, true-peak, spectrum and voice-quality analysis.

What you can do
  • Measure loudness, true-peak, LRA, stereo and tonal balance of a URL or local file
  • Check a file against delivery targets such as Spotify, podcast or broadcast, with deltas and a fix command
  • Get time-series loudness and waveform peaks, FFT spectrum and band energies
  • Run voice QA, speech segments, signal indexing and named profiles (voice, master, provenance, room, pitch and more)
  • Compare two sources A/B and batch up to 20 sources in one call
When to use it
Useful when an assistant needs to judge audio masters, mixes or voice recordings: checking whether a file meets a streaming or broadcast loudness target, deciding if a take is usable, or QA-ing a folder or release.
Requirements
Node 18 or newer, run via npx; no ffmpeg or native dependencies. Optional AUDIOLAB_API_KEY for higher limits; AUDIOLAB_API_BASE and AUDIOLAB_TIMEOUT_MS can be set. Network access to audiolab.tools is required.
Before you install
Audio is uploaded to audiolab.tools: URLs are fetched server-side and local files are sent to the API, so nothing stays on the machine. Without a key the keyless trial allows 20 calls a month per IP, no batches and files up to 4 MB. Some profiles need a paid plan. Local path input works only in this stdio server.

Installation

In SourceWeft

  1. Open Audiolab in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

@audiolabtools/mcp-server

[Listed on mcpservers.org]

MCP (Model Context Protocol) server that gives any MCP-capable AI (Claude Desktop, Claude Code, Cursor, and others) ten audio-analysis tools, backed by the hosted AudioLab API. It is a thin HTTP client: no local audio engine, no ffmpeg, nothing to compile. It can measure a public URL or a local file on your machine, but the measuring always happens on the hosted API: the file is read here and uploaded there (see Privacy).

Install

Point your MCP client at the package via npx (nothing to install globally). No account needed for a first score:

json
{  "mcpServers": {    "audiolab": {      "command": "npx",      "args": ["-y", "@audiolabtools/mcp-server"]    }  }}

Without a key you are on the keyless trial: 20 calls a month and 3 a minute per IP address, for single analyses of a URL or a local file up to 4 MB. Batches and larger files need a key. A free key gives 1,000 calls and 2 GB a month, no card: sign in at https://audiolab.tools/account, generate one, and add it:

json
"env": { "AUDIOLAB_API_KEY": "al_live_yourkey" }

Requirements

  • Node ≥ 18: uses the built-in global fetch + AbortSignal.timeout.
  • Optionally an AUDIOLAB_API_KEY (see Install). No ffmpeg, no native dependencies.

Tools

Every tool takes one audio source: a public url or a local path:

  • { url: "https://…" }: a public https URL the API fetches server-side.
  • { path: "./mix.wav" }: a file on the machine running this server. Files up to 4 MB are sent inline; larger files (up to 150 MB) upload over a signed URL, are analysed, and are swept from storage within the hour. (Local path works only in this stdio server, not the remote /mcp endpoint.)
ToolReturns
analyze_loudnessIntegrated LUFS (EBU R128 / BS.1770-4), true-peak (dBTP), LRA, crest factor, stereo correlation, mono compatibility, tonal balance
check_targetPass/fail vs a delivery target (spotify / apple-music / youtube / tidal / amazon-music / podcast / ebu-broadcast / atsc-broadcast, or target:"custom" + lufs+tp), with per-metric deltas and an ffmpeg loudnorm fix command
analyze_timeseriesShort-term LUFS over time + downsampled waveform peaks (waveformPoints?)
get_spectrumFFT magnitude data + 7-band energies
analyze_voiceVoice QA: speech/silence ratio, speaking rate, SNR, noise floor, pause energy, sibilance & clipping risk
get_speech_segmentsVoiced regions with start/end + per-segment RMS (auto-trim, chapters)
index_signalContent-type guess, tags, clipping/silence regions, brightness & dynamics buckets
analyze_profileOne named question, voice, master, provenance, dataset, environment, broadcast, loop, room (reverberation from a clap, a pop, an impulse response or a sweep; pass roomSource), chain (lost packets) or pitch (where a voice sits and how clean it is), answered with only the lenses it needs. These ten need a paid plan; the free tier gets the basic profile, keyed by stable lens id. Add series:true for the curves, per-block lanes and per-phrase values. Carries a note when the profile’s voice lenses land on non-speech material. Full catalogue: https://audiolab.tools/lenses
compare_loudnessA/B on two sources (urlA/pathA + urlB/pathB), returns both results
analyze_batchOne route over up to 20 sources in a single call (urls and/or paths), per-item ok/data/error. For folder QA, library indexing, or checking a whole release against a target. Each item meters as one call

Example asks to your AI:

  • “Analyze the loudness of https://example.com/track.wav” → analyze_loudness with url
  • “Is this take usable?” → analyze_profile with profile:"voice"
  • “Has this file been re-encoded, and is it all one source?” → analyze_profile with profile:"provenance"
  • “Run loudness on ./master.wav” → analyze_loudness with path
  • “Does ./mix.mp3 pass Spotify?” → check_target with path + target:"spotify"

Configuration (env)

VarDefaultPurpose
AUDIOLAB_API_KEY– (optional)Your API key. Without it: the keyless trial (20 calls a month per IP, no batches, files up to 4 MB).
AUDIOLAB_API_BASEhttps://audiolab.tools/v1Override the API base (must be https://).
AUDIOLAB_TIMEOUT_MS330000Per-request timeout in milliseconds (long files and batches stream server-side and can legitimately take minutes).

Privacy

Analysis happens on the AudioLab API, so the audio does reach audiolab.tools: a url is fetched server-side, and a local path is read here and uploaded to the API (small files in the request body; larger files via a private one-shot signed upload into EU storage). The API returns numbers only and does not keep your audio: a direct request is decoded and discarded inside the request, and a signed upload is swept from storage within the hour (see https://audiolab.tools/privacy). This package has no telemetry and writes nothing to disk. There is no offline mode, and the engine is not published as an installable package. If audio must never leave the machine, don't use a hosted analyser; the in-browser labs on the website measure on-device, but they are for people, not for agents.

Limits

  • Local files: up to 150 MB (host bigger ones at a public URL).
  • Duration: loudness routes (analyze_loudness, check_target, analyze_timeseries, get_spectrum) handle long files (podcast episodes, full sets, up to ~3 h) via server-side streaming; voice/signal routes are limited to ~7 minutes.
  • One file per call (agents loop for many); one-shot (no streaming/realtime).
  • Rate and monthly limits are enforced by the API, per key (per IP address on the keyless trial).

Smoke test

sh
node hosted-server.mjs --selftest   # verifies the 10 tools + guards; no network

License

MIT © Nathan Renting

Source: README.md at commit 70a5654

Tools

0
SourceWeft started this package once in an isolated sandbox, without credentials, to list its tools. That failed: the server did not start.

Version history

8
  1. v0.5.0LatestOct 30, 2026
  2. v0.4.5Oct 20, 2026
  3. v0.4.4Oct 12, 2026
  4. v0.4.3Oct 12, 2026
  5. v0.4.2Oct 6, 2026
  6. v0.4.1Sep 26, 2026
  7. v0.4.0Sep 20, 2026
  8. v0.3.2Sep 16, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts