WhatsApp MCP

whatsapp-mcp

A WhatsApp MCP server for Claude, built directly on whatsmeow. Encrypted at rest, prompt-injection-scrubbed, draft-and-confirm on every send, full audit trail, daily CI security gates. Actively maintained.

Why this one?

The most-starred WhatsApp MCP (lharries/whatsapp-mcp, 5.6K stars) is the architectural reference for this pattern, but has not shipped since July 2025 and leaves the lethal-trifecta problem entirely to the user. This implementation closes the gaps:

	Canonical	This implementation
Last shipped	July 2025	Active
DB encryption	Plain SQLite	SQLCipher with key in the platform secret store (macOS Keychain / Windows Credential Manager / libsecret)
Prompt-injection scrubber	None	Every inbound message
Send safety	Fires immediately	Mandatory confirm_send between draft and delivery
Audit log	None	Every tool call, 30-day retention
Voice notes	Not transcribed	whisper.cpp local, Spanish-tuned default
LID alias resolution	Open issue cluster upstream	Shipped, with backfill migration for legacy threads
CI security	None	govulncheck + pip-audit + Dependabot, daily

Not a fork. The Go bridge is built directly against whatsmeow; the Python MCP layer and SQLite schema are original. Other implementations (lharries, LukasHaas, verygoodplugins) were read as reference only.

What this gives you

Claude can:

• Read your WhatsApp chats, messages, and contacts
• Search messages with accent-insensitive, typo-tolerant matching
• Transcribe voice notes locally via whisper.cpp (Spanish-tuned by default)
• Resolve LID (Linked IDentifier) names instead of numeric placeholders
• Send text messages, reactions, and reply-quotes, with a mandatory confirm_send step between draft and delivery
• Pull matching CRM context from your Obsidian vault when reading a chat
• See only prompt-injection-scrubbed message text, never raw adversarial input

Everything runs locally on your machine. No cloud sync. No telemetry. Optional OpenAI Whisper backend is opt-in, off by default.

Architecture

Two components, both local:

• whatsapp-bridge/ (Go). Binds to 127.0.0.1 only. Wraps whatsmeow for the WhatsApp Web multidevice protocol. Owns SQLite persistence with SQLCipher encryption. Handles QR and pairing-code auth (live-refreshing terminal QR with Windows-safe rendering, plus a headless auth API — GET /api/auth/qr, POST /api/auth/pair-phone, POST /api/auth/reconnect — so a GUI or supervisor can drive pairing without a terminal), media up/download, session recovery from StreamReplaced conflicts, call history capture. Exposes a REST API the Python MCP layer consumes.
• whatsapp-mcp-server/ (Python, FastMCP). Consumes the Go bridge REST API. Exposes 11 MCP tools to Claude: full read surface (chats, messages, contacts), accent-insensitive search, presence (typing, online, mark-read), and text-send + reactions + reply-quotes with mandatory confirm_send. Runs via uv and stdio transport.

Install

Open Claude Code, paste:

/plugin marketplace add adelaidasofia/whatsapp-mcp
/plugin install whatsapp-mcp@whatsapp-mcp

This installs the Python MCP server side. The Go bridge still needs the one-time QR pairing flow with your phone — see the legacy install block below for those steps.

Manual install (full Go bridge + QR pairing)

See SETUP.md for step-by-step install per OS. In short:

1. Grab a prebuilt bridge binary from Releases (Windows/macOS/Linux — no compiler needed), or build from source (Go 1.26+ and a C toolchain)
2. Python 3.11+ and uv for the MCP server layer
3. Clone this repo; verify with scripts/check_prerequisites.sh (Windows: scripts\check_prerequisites.ps1)
4. Start the bridge: ./bin/whatsapp-bridge (Windows: .\bin\whatsapp-bridge.exe)
5. Scan the QR (it refreshes in place — always scan the one on screen), or pair by typed code with --pair-phone +15551234567
6. Register the MCP in your Claude Code .mcp.json
7. Restart Claude Code

FFmpeg and whisper.cpp are only needed if you enable voice-note transcription (off by default).

Configuration

All configurable via environment variables. See .env.example for the full list.

Key variables:

Variable	Default	Purpose
WHATSAPP_BRIDGE_PORT	8080	Go bridge REST API port
WHATSAPP_DB_PATH	$HOME/.claude/whatsapp-mcp/store/messages.db	Encrypted SQLite database
WHATSAPP_MEDIA_PATH	$HOME/.claude/whatsapp-mcp/media/	Media file storage
WHATSAPP_VAULT_CRM_PATH	empty	Absolute path to your vault CRM folder for auto-injection (e.g., Obsidian 👤 CRM/). When unset, CRM injection is disabled.
WHATSAPP_WHISPER_BACKEND	off	off (zero-config boot), local-cpp (private, needs a whisper model), or openai-api (opt-in)
WHATSAPP_WHISPER_API_KEY	empty	Required only when backend is openai-api
WHATSAPP_WHISPER_MODEL	large-v3	whisper.cpp model name
WHATSAPP_SCRUB_PROMPT_INJECTION	true	Strip known prompt-injection patterns from incoming messages before Claude sees them
WHATSAPP_AUDIT_LOG	true	Log every tool call to audit.log
WHATSAPP_ENCRYPT_DB	true	Enable SQLCipher DB encryption; key in the platform secret store (macOS Keychain / Windows Credential Manager / libsecret)
WHATSAPP_DB_KEY	empty	Explicit 64-hex-char SQLCipher key override (skips the platform store). Escape hatch for headless/CI/custom secret managers, and the recovery path when the secret store cannot be read — see below

The DB key and WHATSAPP_DB_KEY

With WHATSAPP_ENCRYPT_DB=true (the default), the bridge encrypts the message store with a 256-bit SQLCipher key kept in the platform secret store. The key lifecycle is deliberately conservative, because a wrong key silently orphans every stored message:

• A fresh key is minted only when the secret store definitively answers "no such item" (macOS errSecItemNotFound, Windows ERROR_NOT_FOUND, libsecret clean miss) and no non-empty store database exists yet.
• Any other failed read — locked keychain, no D-Bus session, revoked access — makes the bridge exit with an error instead of minting: the key may still exist, and overwriting it would make the encrypted store permanently undecryptable. The error names the fix (e.g. security unlock-keychain).
• If the secret store has no key but a populated store database exists, the bridge also refuses to mint and asks you to supply the original key.

WHATSAPP_DB_KEY (64 hex chars = 32 bytes, e.g. openssl rand -hex 32) is the escape hatch for all of these: when set, it is used directly and the platform secret store is never touched. Use it for headless/CI machines, custom secret managers, restoring a store on a new machine, or booting while the platform store is unavailable.

Security

This MCP is the highest-trust component in your Claude stack because every WhatsApp message you receive flows through it. See SECURITY.md for the threat model, tool risk-tier classification, and the full list of hardening decisions.

Short version:

• Bridge binds to 127.0.0.1 only, never 0.0.0.0
• SQLite encrypted at rest with SQLCipher; key stored in the platform secret store (macOS Keychain / Windows Credential Manager / libsecret), with an explicit WHATSAPP_DB_KEY escape hatch
• Every tool call logged to audit.log with 30-day retention
• Send tools require an explicit confirm_send step between draft and delivery
• Incoming message text passes through a prompt-injection scrubber before Claude sees it
• whatsmeow pinned to a specific commit; upgrades require diff review
• No telemetry, no external API calls by default

Status

v0.1.0, actively maintained.

Shipped: live-refreshing QR (in-place redraw on rotation, Windows-safe rendering, auto fresh batch on expiry) + pairing-code auth (typed 8-char code, Android + iOS) + headless auth API for supervisors, full read surface (chats, messages, contacts), accent-insensitive NFD-normalized search, LID alias resolution with backfill migration for legacy threads, Baileys-store import for one-shot history migration, vault-format markdown export, local whisper.cpp voice transcription, presence (typing, online, mark-read), text-send with mandatory confirm_send, reactions, reply-quotes, prompt-injection scrubber, SQLCipher-encrypted persistence with macOS Keychain key handling, audit log, CI security gates.

Not yet shipped: media-send (image, document), audio-message-send (FFmpeg-Opus path), group broadcast helpers.

See CHANGELOG.md for full history.

MCP Registry

Published on the official MCP Registry under io.github.adelaidasofia/whatsapp-mcp. Two live channels:

• .mcpb bundle (canonical, recommended) — one-click install in Claude Desktop / Cursor / any MCPB-aware client. Published as a GitHub release artifact at releases/latest/download/whatsapp-mcp.mcpb. The release manifest carries the SHA256 for tamper detection.
• PyPI package (adelaidasofia-whatsapp-mcp) — historical; available via uvx adelaidasofia-whatsapp-mcp for stdio-installer flows. The unprefixed names (whatsapp-mcp, whatsapp-mcp-server) are taken by unrelated projects on PyPI, hence the username-prefixed namespace.

The verification marker mcp-name: io.github.adelaidasofia/whatsapp-mcp is embedded in this README (HTML comment near the top) so the registry can verify package-to-server ownership at publish time.

Publishing pipeline: built and shipped via the Mycelium MCP publishing pipeline (two-phase: .mcpb bundle build, then gh release + mcp-publisher publish). The same pipeline produced all 16 sibling MCPs in this family.

Related MCPs

Same author, same architecture pattern (FastMCP, draft+confirm on writes where applicable, vault auto-export, MIT):

• slack-mcp — multi-workspace Slack
• imessage-mcp — macOS iMessage
• google-workspace-mcp — Gmail / Calendar / Drive / Docs / Sheets
• apollo-mcp — Apollo.io CRM + sequences
• substack-mcp — Substack writing + analytics
• luma-mcp — lu.ma events
• parse-mcp — markitdown / Docling / LlamaParse router
• rescuetime-mcp — RescueTime productivity data
• graph-query-mcp — vault knowledge graph queries
• graph-autotagger-mcp — wikilink suggestions from the graph
• investor-relations-mcp — seed-raise pipeline tracker
• vault-sync-mcp — bidirectional vault sync

Telemetry

This plugin sends a single anonymous install signal to myceliumai.co the first time it loads in a Claude Code session on a given machine.

What is sent:

• Plugin name (e.g. slack-mcp)
• Plugin version (e.g. 0.1.0)

What is NOT sent:

• No user identifiers, names, emails, tokens, or API keys
• No file paths, message content, or anything from your work
• No IP address is stored after dedup processing

Why: Helps the maintainer know which plugins people actually install, so attention goes to the ones that get used.

Opt out: Set the environment variable MYCELIUM_NO_PING=1 before launching Claude Code. The hook will skip the network call entirely. Already-pinged installs leave a sentinel at ~/.mycelium/onboarded-<plugin> — delete it if you want to reset state.

License

MIT. See LICENSE.

Not affiliated with WhatsApp or Meta

WhatsApp is a trademark of Meta Platforms, Inc. This project is an independent open-source tool that uses WhatsApp's public web-multidevice protocol. Use of this tool may violate WhatsApp's Terms of Service. Use at your own risk. The authors provide no warranty and accept no liability for account suspension, data loss, or other consequences.

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Built by Mycelium AI. MIT license.