# voice-truthgate-mcp [Health: Active]

**Category:** 💻 Developer Tools  
**Repository:** https://github.com/Hei33enberg/voice-truthgate  
**GitHub Stars:** 1  
**Views:** 0  
**Installs:** 0  
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**Directory Page:** https://allmcps.com/mcp/voice-truthgate-mcp

## Description
Honest voice authenticity for AI agents: enrol a voice, verify a call clip. Signal, not verdict.

## Claude Desktop Quick Installation
Install path detected from listing signals. Uses `npx` (confidence: high):

```json
"mcpServers": {
  "voice-truthgate-mcp": {
    "command": "npx",
    "args": ["-y","@mosadd/voice-truthgate-mcp"]
  }
}
```

## Documentation & README

<div align="center">

# Voice Truthgate by mosADD

*(formerly VoiceCheck)*

### Is this really my contact — live? Honest voice authenticity. Open-core, MIT.

[![CI](https://github.com/Hei33enberg/voice-truthgate/actions/workflows/ci.yml/badge.svg)](https://github.com/Hei33enberg/voice-truthgate/actions/workflows/ci.yml)
[![License: MIT](https://img.shields.io/badge/License-MIT-informational.svg)](./LICENSE)
[![npm: MCP](https://img.shields.io/npm/v/@mosadd/voice-truthgate-mcp?label=%40mosadd%2Fvoice-truthgate-mcp)](https://www.npmjs.com/package/@mosadd/voice-truthgate-mcp)
[![Privacy: on-device](https://img.shields.io/badge/privacy-on--device-brightgreen.svg)](#privacy--on-device-by-design)
[![Part of mosADD](https://img.shields.io/badge/part%20of-mosADD-5af082)](https://github.com/Hei33enberg/mosADD-OS)
[![Try it live](https://img.shields.io/badge/try%20it-live-8A2BE2.svg)](https://mosadd.com/voice-truthgate)

Voice authenticity that's **honest about its own limits**. It never gives you a bare
"REAL / FAKE" — it gives you a **confidence signal** and a plain disclaimer, because getting
this wrong about a real person is harmful.

**[▶ Try it live](https://mosadd.com/voice-truthgate)** &nbsp;·&nbsp;
[How it works](https://mosadd.com/voice-truthgate/how-it-works) &nbsp;·&nbsp;
[Model card](https://mosadd.com/model-card) &nbsp;·&nbsp;
[API docs](./docs/VOICE-TRUTHGATE-API.md)

</div>

---

## Why "detect the deepfake" is the wrong game — and what we do instead

The whole voice-AI industry races to **generate** speech; almost nobody ships an honest tool
to tell you what's real. The naïve answer — a standalone "is this audio AI?" detector — is a
**losing game**, and we have our own numbers to prove it: on modern premium TTS, our best
single-clip detector measured **AUC ≈ 0.61** (barely better than a coin). Anyone selling you
"99% deepfake detection" is selling snake oil.

So Voice Truthgate asks a **better, answerable** question: **"is this really my contact,
live?"** We answer it by **fusing signals**, not by guessing at a waveform:

- **L0 — Identity.** *Who* is this, and are they a known human or a known agent? (An agent
  *should* sound synthetic — that's not an alarm.)
- **L1 — Voiceprint.** Does the voice match *this specific person's* enrolled print? Strong at
  rejecting a **different** human (≈0% false accept in our tests, ~4.6% EER on clean speech).
- **L2 — Acoustic.** A weak, abstain-heavy synthetic-speech signal (the on-device band below).
- **L3 — Live rhythm.** *The un-copyable part* — see [the moat](#the-moat-fake-live-conversation-not-fake-file).

Every layer is a **signal, not a verdict**, fused with the others and shipped with a
disclaimer. We would rather abstain than be confidently wrong.

### The honest proof: why voiceprint alone isn't enough

We ran a **targeted-clone test** on our own voiceprint engine — clone an enrolled person, then
try to pass as them. Result: a targeted clone was **accepted 63% of the time** at our operating
threshold, and **no threshold** cleanly separates "a clone of you" from "you" without also
rejecting real callers. That's not a flaw we hide — it's *the reason the product fuses identity
+ voiceprint + liveness instead of trusting the voice alone.* Voice is one signal. Never the
whole decision.

---

## Three ways to use it

### 1. Open SDK — on-device, MIT, zero infra

The acoustic band (L2) runs **in the browser** — your audio never leaves the device.

```ts
import { analyzeVoiceTruthgate } from "@mosadd/voice-truthgate";

// Decode your audio to mono PCM (a Float32Array), e.g. at 16 kHz.
const result = await analyzeVoiceTruthgate({ samples, sampleRate: 16000 });

console.log(result.band.label);  // "Likely authentic" | "Uncertain" | "Likely synthetic"
console.log(result.confidence);  // 0..1 — lead with the band, not this number
console.log(result.disclaimer);  // ALWAYS present — render it next to the result
```

Inject your own trained model as an optional server detector — the SDK never hard-codes an
endpoint or key, and it **fails open** (unreachable model ⇒ the on-device band still stands and
never silently becomes "authentic"):

```ts
import { analyzeVoiceTruthgate, createHeuristicDetector, createServerDetector } from "@mosadd/voice-truthgate";

const server = createServerDetector({
  analyze: async (payload) => callYourModel(payload), // → { confidence, modelVersion }
  version: "your-model-v1",
});
const result = await analyzeVoiceTruthgate({ samples, sampleRate: 16000 },
  { detectors: [createHeuristicDetector(), server] });
```

> The SDK packages aren't on npm yet — clone this repo (`npm install` wires the workspaces) or
> vendor `packages/*`. Runnable demo: **`npm run example`**, or open `examples/browser-check`.

### 2. MCP tool — give any AI agent an authenticity check

Live on npm. Enrol a voice and verify a call clip **from Claude, Cursor, your own fleet — any
MCP agent**:

```bash
npx -y @mosadd/voice-truthgate-mcp
```

```json
{ "mcpServers": { "voice-truthgate": {
  "command": "npx", "args": ["-y", "@mosadd/voice-truthgate-mcp"],
  "env": { "VTG_API_KEY": "vtg_live_your_key" }
} } }
```

Tools: `voice_truthgate_enroll`, `voice_truthgate_verify`, `voice_truthgate_list_subjects`. See
[`mcp/`](./mcp).

### 3. Market API — enrol / verify from any app

For contact centres, IVRs, or any backend. Enrol the voices you protect, then verify a call
clip against a subject → an honest banded verdict (`likely_same_person` / `likely_different_person`
/ `inconclusive`) with a synthetic-voice caution:

```bash
curl -X POST "$VTG_URL" -H "X-API-Key: $KEY" \
  -F action=verify -F subject_id=ceo -F audio=@incoming_call.wav
```

Full reference: **[docs/VOICE-TRUTHGATE-API.md](./docs/VOICE-TRUTHGATE-API.md)** · machine-readable
**[OpenAPI spec](./docs/openapi.yaml)** (import as an OpenAI GPT Action / any tool).

> **Drop it into your stack:** copy-paste recipes for **Claude, OpenAI (GPT Action + Agents SDK),
> Vercel AI SDK, v0, and LangChain** → **[docs/USE-IN-YOUR-AGENT.md](./docs/USE-IN-YOUR-AGENT.md)**.
> One MCP server, every ecosystem.

---

## The moat: fake live *conversation*, not fake *file*

A live AI impersonation runs **speech → STT → LLM → TTS** — which is **half-duplex and
turn-based**. It categorically **cannot** reply in <~300 ms, **overlap** you, **backchannel**
("mhm" while you talk), or interrupt mid-sentence. Humans in live conversation do all four
constantly. **We can measure this because we own the channel's millisecond, per-speaker turn
timing** — nobody holding only an audio file can. (In corpus analysis, *overlap rate alone*
separates a bot pipeline from human turn-taking almost perfectly.)

This is L3, and it's the un-copyable signal. It's held to the same honesty rail as everything
else: it **only fires from a profile calibrated on real labelled turn logs** — until then it
measures, never accuses. That calibration is the frontier we're building toward.

---

## The three confidence bands (L2 acoustic)

| Band | Score | What it means |
|---|---|---|
| 🟢 **Likely authentic** | `0.00 – 0.35` | No strong synthetic-voice signals. This does **NOT** prove the voice is real — a good deepfake can score here. |
| 🟡 **Uncertain** | `0.35 – 0.65` | Mixed / weak signals. Inconclusive; prefer a longer, uncompressed sample + human review. |
| 🔴 **Likely synthetic** | `0.65 – 1.00` | Signals consistent with AI-generated or cloned speech. **NOT** proof — verify with a human before acting. |

Every result carries this disclaimer, verbatim:

> **This is a signal, not a verdict.** Automated voice-authenticity detection is probabilistic
> and can be wrong in both directions. Do not use this result alone to accuse, identify, or make
> legal/forensic decisions about a person.

## Architecture (the open SDK)

Two stages, both **on-device**; an optional trained model is *injected* by the host app.

```
        ┌──────────────── your device / browser (nothing leaves it) ────────────────┐
 mic /  │  record or      decode to        STAGE 1: instant heuristic                │
 file ──┼─▶ upload  ─────▶ 16 kHz mono ───▶ (pure DSP, 0 MB, default)  ──────────────┼──▶ band
        │                  Float32 PCM   └▶ STAGE 2: stronger model (opt-in) ─────────┼──▶  +
        │                                   (a real classifier via transformers.js)  │    disclaimer
        └──────────────────────────────────────────────────────────────────────────┘
                     (optional) injected SERVER detector — your model, your transport;
                      authoritative when it answers, FAIL-OPEN when it doesn't.
```

Fusion is **band-first and fails to "unknown", never to "safe"** — nothing usable ⇒
`available: false`, band `uncertain`, never `likely-authentic`. Deeper design:
[docs/ARCHITECTURE.md](./docs/ARCHITECTURE.md).

## Packages

| Package | Role |
|---|---|
| [`@mosadd/voice-truthgate`](./packages/voice-truthgate) | The brains — fuses the stages into an honest band, always attaches the disclaimer. |
| [`@mosadd/voice-analyzer-core`](./packages/voice-analyzer-core) | Stage 1: the instant, pure-DSP on-device heuristic. |
| [`@mosadd/detection-sdk`](./packages/detection-sdk) | Pluggable `Detector` / `Verdict` frame + fail-open `runDetectors`. |
| [`@mosadd/threat-engine`](./packages/threat-engine) | Shared severity/scoring primitives (transitive dependency). |
| [`@mosadd/voice-truthgate-mcp`](./mcp) | **On npm** — the MCP server (enrol/verify tools for AI agents). |

## Honesty — the caveats, stated plainly

- **Standalone detection is a losing game.** Our own single-clip detector measured **AUC ≈ 0.61**
  on modern premium TTS. The product's value is **fusion + honesty**, not a magic detector.
- **Voiceprint is foolable by a targeted clone** (~63% accepted in our test) → it's a signal to
  *fuse*, never a standalone verdict. Great at rejecting a *different* human; weak against a
  clone *of you*.
- **Codec compression is the #1 accuracy killer** (Opus / MP3 / telephony, −10–40%). Prefer
  uploaded, less-compressed clips.
- **L3 live-rhythm is un-calibrated today** — it measures but does not accuse until fit on real
  labelled turn logs (weight-zero-until-calibrated).
- **Short, noisy, or distressed real speech** raises false positives; accuracy varies by language
  and accent.
- **npm:** the MCP server is published; the SDK packages are publish-*ready* but not yet on npm.
- **Not for accusations, forensics, or legal decisions.** See each package's `MODEL_CARD.md`.

## Privacy — on-device by design

The public checker has nowhere to send your audio: Stage 1 and the opt-in Stage 2 run locally.
The SDK ships **no** transport and **no** endpoint. A server model (or the market API) is
something you *opt into*; the SDK sends nothing on its own. The market API holds enrolled
voiceprints server-side under strict access control and returns only a **signal**, never the raw
biometric.

## Part of the mosADD ecosystem

Voice Truthgate is the **authenticity / trust layer** of [mosADD](https://mosadd.com) — the
open comms stack for AI agents and the humans who direct them. It composes with:

- **[mosADD-OS](https://github.com/Hei33enberg/mosADD-OS)** — the **comms layer**: E2EE DMs,
  channels, web rooms, and email, all exposed as MCP tools (`npx -y @mosadd/mcp`). Your agents
  talk and coordinate there; Voice Truthgate answers *"is this contact really who they claim,
  live?"* on the same channel.
- **[mosadd.com](https://mosadd.com)** — the product + the live checker + the in-app add-on.

Both are open, both publish under the `@mosadd/*` npm scope. (mosADD-OS is Apache-2.0; this repo
is MIT — the public authenticity SDK stays maximally permissive.)

## Roadmap

- [x] Publish the MCP server to npm (`@mosadd/voice-truthgate-mcp`)
- [ ] Publish the SDK packages to npm (`@mosadd/*`)
- [ ] Calibrate L3 live-rhythm on real labelled turn logs (the moat — turn it from measure to trigger)
- [ ] Threat-informed, always-fresh accuracy benchmark (per-condition numbers, no headline claim)
- [ ] Quantize the opt-in Stage-2 model (~379 MB → ~95 MB)

## Contributing

Issues and PRs welcome — see [CONTRIBUTING.md](./CONTRIBUTING.md) and the
[Code of Conduct](./CODE_OF_CONDUCT.md). **Keep the honesty rails intact** (no bare verdicts,
keep the disclaimer, no accuracy claims). Security: [SECURITY.md](./SECURITY.md).

## License

[MIT](./LICENSE) © mosADD. Third-party attributions (transformers.js, the referenced Hugging
Face model) are in [NOTICE](./NOTICE).