nab

Token-optimized web fetcher + multilingual ASR + URL watcher. MCP 2025-11-25 compliant. Rust. macOS arm64 first, cross-platform.

demo

nab is a single Rust binary that does three things very well: it fetches any URL as clean markdown (with your real browser cookies and anti-bot evasion), it analyzes any audio or video file with on-device multilingual ASR and speaker diarization, and it watches any URL for changes and pushes notifications when content moves. Everything runs locally. There are no API keys to set up by default. The output is shaped for LLM context windows.

Quick start

brew install MikkoParkkola/tap/nab                            # install
nab fetch https://news.ycombinator.com                        # fetch as markdown
nab models fetch fluidaudio                                   # download ASR model
nab analyze interview.mp4 --diarize                           # transcribe + identify speakers
nab watch add https://status.openai.com --interval 5m         # subscribe to changes

Features

Command	What it does
`nab fetch <url>`	Fetch any URL as clean markdown. HTTP/3, browser cookie injection (Brave / Chrome / Firefox / Safari / Edge / Dia), 1Password auto-login, fingerprint spoofing, 11 site providers, query-focused extraction, token budget.
`nab analyze <video\|audio>`	Transcribe and diarize. FluidAudio (Parakeet TDT v3) on Apple Neural Engine, 131x realtime on a 2-hour clip, word-level timestamps, 25 EU languages, optional Qwen3-ASR for zh/ja/ko/vi, optional active reading via MCP sampling.
`nab watch add <url>`	Monitor a URL and push notifications via subscribable MCP resources. RSS for the entire web. Conditional GETs, semantic diff, adaptive backoff.
`nab models fetch <name>`	Persistent install of inference model binaries. Currently `fluidaudio`. Whisper and sherpa-onnx land in Phase 3.
`nab-mcp`	MCP 2025-11-25 server. stdio + Streamable HTTP. 11 tools, 3 prompts, 2+N resources, structured logging, sampling, roots, elicitation.
`nab::content::ocr`	Apple Vision OCR engine. 15 languages. Apple Neural Engine accelerated. ~10-50 ms per image. macOS only.

Installation

Homebrew (macOS, recommended)

brew tap MikkoParkkola/tap
brew install nab

From crates.io

cargo install nab

Requires Rust 1.93 or newer.

Pre-built binary

cargo binstall nab

Or download directly from GitHub Releases:

Platform	Binary
macOS Apple Silicon	`nab-aarch64-apple-darwin`
macOS Intel	`nab-x86_64-apple-darwin`
Linux x86_64	`nab-x86_64-unknown-linux-gnu`
Linux ARM64	`nab-aarch64-unknown-linux-gnu`
Windows x64	`nab-x86_64-pc-windows-msvc.exe`

From source

git clone https://github.com/MikkoParkkola/nab.git
cd nab
cargo install --path .

Usage

Fetch

# Basic fetch — auto-detects browser, returns markdown
nab fetch https://example.com

# Use cookies from a specific browser
nab fetch https://github.com/notifications --cookies brave

# 1Password auto-login (TOTP/MFA supported)
nab fetch https://internal.company.com --1password

# Google Workspace (Docs, Sheets, Slides) with comments
nab fetch --cookies brave "https://docs.google.com/document/d/DOCID/edit"

# Query-focused extraction — only sections relevant to "authentication"
nab fetch https://docs.example.com --focus "authentication" --max-tokens 2000

# Output JSON with confidence scores
nab fetch https://example.com --format json

# Batch fetch with parallelism
nab fetch --batch urls.txt --parallel 8

Common flags for fetch:

Flag	Description
`--cookies <browser>`	`auto`, `brave`, `chrome`, `firefox`, `safari`, `edge`, `none`
`--1password` / `--op`	1Password credential lookup + auto-login
`--proxy <url>`	HTTP or SOCKS5 proxy
`--format <fmt>`	`full` (default), `compact`, `json`
`--focus <query>`	BM25-lite query-focused extraction
`--max-tokens <n>`	Structure-aware token budget
`--raw-html`	Skip markdown conversion
`--diff`	Show what changed since the last fetch
`--session <name>`	Persistent named session with cookie store
`-X <method>` `-d <data>`	HTTP method + body
`-o <path>`	Write body to file

Analyze

nab analyze transcribes audio and video files locally. The default backend on macOS arm64 is FluidAudio, which runs Parakeet TDT v3 on the Apple Neural Engine.

# Download the ASR model (~600 MB, one-time)
nab models fetch fluidaudio

# Transcribe a video
nab analyze interview.mp4

# Add speaker diarization (PyAnnote community-1)
nab analyze interview.mp4 --diarize

# Force a language hint (BCP-47)
nab analyze podcast.mp3 --language fi

# Word-level timestamps
nab analyze talk.mp4 --word-timestamps

# Active reading: nab uses MCP sampling to look up references mentioned in the audio
nab analyze interview.mp4 --active-reading

# Expose speaker embeddings for matching against hebb's voiceprint database
nab analyze interview.mp4 --diarize --include-embeddings

# Output JSON
nab analyze podcast.mp3 --format json

Real numbers from a 2 h 09 m English audio file (Karen Hao interview, MacBook Pro M-series):

Metric	Value
Wall time	59.6 s
Realtime factor	131x
FluidAudio mean confidence	97.18 %
Audio extraction (ffmpeg)	~650x realtime

Backend	Platform	Languages	Diarization
`fluidaudio` (default on macOS arm64)	macOS arm64	25 EU languages, +zh/ja/ko/vi via Qwen3-ASR (opt-in)	PyAnnote community-1
`sherpa-onnx` (Phase 3)	Linux/x86, macOS, Windows	Parakeet ONNX, 25+ langs	sherpa-onnx pyannote-seg-3.0
`whisper-rs` (Phase 3)	Universal fallback	whisper-large-v3-turbo, 99 langs	none

Watch

nab watch turns any URL into a subscribable resource. MCP clients receive notifications/resources/updated when the content changes.

nab watch add https://news.ycombinator.com --interval 10m
nab watch add https://example.com/pricing --interval 1h --selector "table.pricing"
nab watch add https://api.openai.com/status --interval 5m --notify-on regression
nab watch list
nab watch logs <id>
nab watch remove <id>

Per-watch options:

Flag	Default	Description
`--interval <duration>`	1h	Polling interval (`5m`, `1h`, `24h`)
`--selector <css>`	none	CSS selector to scope diff to one element
`--notify-on <kind>`	`any`	`any`, `regression`, `semantic`
`--diff <kind>`	`semantic`	`text`, `semantic`, `dom`

The poller uses conditional GETs (If-None-Match, If-Modified-Since), so 304 responses cost effectively nothing. Watches with five consecutive failures auto-mute. Adaptive backoff applies on 429 and 503.

Models

nab models list                           # show installed model versions
nab models fetch fluidaudio               # download FluidAudio binary + Parakeet weights
nab models update fluidaudio              # check for upstream updates
nab models verify fluidaudio              # checksum + smoke test

Phase 3 will add whisper and sherpa-onnx subcommands.

MCP integration

nab-mcp is a native Rust MCP server. It runs over stdio (default) or Streamable HTTP. It is fully compliant with MCP protocol version 2025-11-25.

Claude Code / Claude Desktop

Add to your MCP client configuration (~/.config/claude/mcp.json or equivalent):

{
  "mcpServers": {
    "nab": {
      "command": "nab-mcp"
    }
  }
}

Continue / Zed / Cursor / Windsurf

Same shape — point command at the nab-mcp binary.

HTTP transport

nab-mcp --http 127.0.0.1:8765

Bind to localhost by default. Origin checks and MCP-Protocol-Version header validation are enforced per spec.

MCP capabilities

Capability	Status
Tools	11 tools with structured output schemas, annotations, validation errors
Prompts	3 prompts (`fetch-and-extract`, `multi-page-research`, `authenticated-fetch`, `match-speakers-with-hebb`)
Resources	2 static + N dynamic watch resources, all subscribable
Logging	`notifications/message` with RFC 5424 levels
Sampling	nab calls back to the host LLM for active reading, focus extraction, form auto-fill
Roots	`roots/list` queried for workspace-scoped saves
Elicitation	Form mode + URL mode for OAuth/SSO
Argument completion	`completion/complete` for tool args
Server icons	Light + dark SVG
Transports	stdio + Streamable HTTP (resumable, session-scoped)

The 11 MCP tools:

Tool	Description
`fetch`	Fetch URL → markdown, with cookies, focus, token budget, session
`fetch_batch`	Parallel multi-URL fetch with task-augmented async execution
`submit`	Submit a form with CSRF + smart field extraction
`login`	1Password auto-login with TOTP support
`auth_lookup`	Look up 1Password credentials for a URL
`fingerprint`	Generate browser fingerprint profiles
`validate`	Run the validation test suite
`benchmark`	Time URL fetches with stats
`analyze`	Transcribe and diarize audio/video
`watch_create`	Create a URL watch and subscribe
`watch_list` / `watch_remove`	Manage watches

Site providers

nab detects URLs for 11 platforms and uses their APIs or structured data instead of scraping HTML.

Provider	URL pattern	Method
Twitter / X	`x.com//status/`	FxTwitter API
Reddit	`reddit.com/r//comments/`	JSON API
Hacker News	`news.ycombinator.com/item?id=*`	Firebase API
GitHub	`github.com///issues/`, `/pull/*`	REST API
Google Workspace	Docs, Sheets, Slides	Export API + OOXML
YouTube	`youtube.com/watch?v=`, `youtu.be/`	oEmbed
Wikipedia	`.wikipedia.org/wiki/`	REST API
StackOverflow	`stackoverflow.com/questions/*`	API
Mastodon	`/users//statuses/*`	ActivityPub
LinkedIn	`linkedin.com/posts/*`	oEmbed
Instagram	`instagram.com/p/`, `/reel/*`	oEmbed

If no provider matches, nab falls back to standard HTML fetch + markdown conversion.

Architecture

nab is built around a small set of orthogonal subsystems: cmd/ (CLI), bin/mcp_server/ (MCP server), content/ (HTML / PDF / OCR pipeline), analyze/ (ASR + diarization + vision), watch/ (URL monitoring + subscriptions), auth/ (cookies + 1Password + WebAuthn), site/ (per-site providers), and the shared AcceleratedClient (HTTP/3 + connection pool + fingerprint store).

See:

docs/ARCHITECTURE.md — full module map and data flow
docs/sovereign-stack.md — how nab composes with hebb to form a local-first multimodal stack
docs/getting-started.md — new user onboarding

Design notes

The docs/design/ directory tracks recent design proposals:

analyze-v2.md — multilingual ASR + diarization + vision pipeline
url-watch-resources.md — URL watch as MCP subscribable resources
active-reading.md — active reading via MCP sampling
mcp-spec-closure.md — closing the last MCP 2025-11-25 spec gaps

Companion tools

nab is half of a sovereign multimodal stack. The other half is hebb, a neuroscience-inspired memory MCP server. Composition examples:

nab analyze --diarize --include-embeddings → hebb voice_match → speakers labeled with names
nab fetch URL → hebb kv_set → personal sovereign web memory
nab watch add URL → hebb kv_set (on update) → time-series of changes to any web page

See docs/sovereign-stack.md for the full composition story.

Configuration

nab requires no configuration files. It uses smart defaults: auto-detected browser cookies, randomized fingerprints, and markdown output.

Persistent state lives in ~/.nab/:

Path	Purpose
`~/.nab/snapshots/`	Content snapshots for `--diff` change detection
`~/.nab/sessions/`	Saved login sessions
`~/.nab/fingerprint_versions.json`	Cached browser versions (auto-updates every 14 days)
`~/.local/share/nab/watches/`	URL watch state
`~/.local/share/nab/models/`	Installed inference model binaries

Optional plugin configuration at ~/.config/nab/plugins.toml. See docs/getting-started.md for plugin examples.

Environment variables

Variable	Purpose
`HTTPS_PROXY` / `https_proxy`	HTTPS proxy URL
`HTTP_PROXY` / `http_proxy`	HTTP proxy URL
`ALL_PROXY` / `all_proxy`	Proxy for all protocols
`RUST_LOG`	Logging level (e.g., `nab=debug`)
`PUSHOVER_USER` / `PUSHOVER_TOKEN`	Pushover notifications for MFA
`TELEGRAM_BOT_TOKEN` / `TELEGRAM_CHAT_ID`	Telegram notifications for MFA

Library usage

use nab::AcceleratedClient;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let client = AcceleratedClient::new()?;
    let html = client.fetch_text("https://example.com").await?;
    println!("Fetched {} bytes", html.len());
    Ok(())
}

Requirements

Rust 1.93+ for building from source
ffmpeg for analyze and stream commands: brew install ffmpeg
1Password CLI (optional, for credential integration): see 1Password docs

Contributing

See CONTRIBUTING.md for development setup, code style guidelines, testing instructions, and pull request process.

Responsible use

This tool includes browser cookie extraction and fingerprint spoofing capabilities. They are intended for legitimate use cases — accessing your own authenticated content, automated testing, sites where you have authorization. Use responsibly.

License

MIT — see LICENSE.

nab 0.7.1

nab