io.github.Metadrama/obscura-mcp icon

Obscura MCP

by Metadrama

io.github.Metadrama/obscura-mcp

MCP server adapter for Obscura Rust headless browser — web scraping with anti-detection.

obscura-mcp

An MCP server adapter for Obscura, a lightweight Rust headless browser for scraping and AI agent automation.

Exposes Obscura's native CDP capabilities through a clean MCP interface — no Chrome dependency, no heavyweight browser automation.

Installation

npm install -g obscura-mcp

The install is instant — the browser binary (~80 MB) is downloaded lazily on first use. When you run obscura-mcp, it will automatically download and cache the binary.

The binary is cached at ~/.obscura/bin/ and survives npm upgrades.

To use a custom binary path:

export OBSCURA_PATH=/path/to/obscura

Quick Start

# Install
npm install -g obscura-mcp

# Verify
obscura-mcp --version

# Start MCP server
obscura-mcp --transport stdio

# Or with HTTP transport
obscura-mcp --transport streamable-http

Tools

Four tools cover the full browser automation surface — from one-shot page reading to parallel bulk scraping.

browse_page — one-shot page reading

Get content from any page in a single call. Combine output format with optional JavaScript evaluation.

Parameter Type Default Description
url string The URL to visit
format "text" | "markdown" | "html" | "links" | "cookies" "text" Output format
eval string JavaScript expression to evaluate (appended to output)
cookies array Cookies to inject [{name, value, domain?, path?, ...}]

Examples:

browse_page(url: "https://example.com")
browse_page(url: "https://example.com", format: "markdown")
browse_page(url: "https://news.ycombinator.com", format: "links")
browse_page(url: "https://example.com", format: "cookies")
browse_page(url: "https://example.com", eval: "document.title")
browse_page(url: "https://example.com", format: "markdown", eval: "document.title")
format What you get
"text" Plain text — stripped of HTML tags, scripts, styles
"markdown" Clean markdown — uses Obscura's native LP.getMarkdown CDP
"html" Raw HTML markup
"links" All href values — one per line
"cookies" Cookies with name, value, domain, path, expiry

When eval is provided, the JavaScript result is appended to the format output under a --- eval --- divider.


browse_interact — one-shot page actions

Click an element or type text into a page. One call, no session management needed. For multi-step interactions (login → wait → extract), use browse_session instead.

Parameter Type Default Description
url string The URL to visit
action "click" | "type" Action to perform
selector string CSS selector for the target element
text string Text to type (required when action is "type")
cookies array Cookies to inject [{name, value, ...}]

Examples:

browse_interact(url: "https://example.com", action: "click", selector: "a")
browse_interact(url: "https://duckduckgo.com", action: "type", selector: "input[name=q]", text: "search query")

Both actions create a fresh page, perform the action, and close. The page context does not persist — for sequential interactions (type into a form, then click submit), use browse_session instead.


browse_session — multi-step persistent sessions

Create a persistent browser session, interact with it across multiple calls, then close. Sessions auto-close after 5 minutes of inactivity. Multiple sessions can run simultaneously.

Parameter Type Required for Description
action "create" | "close" | "list" | "goto" | "wait" | "extract" | "click" | "type" All What to do
session_id string All except create, list Session ID from create
url string create, goto URL to navigate to
selector string wait, click, type CSS selector
expression string wait (if no selector), extract JavaScript expression
text string type Text to type
timeout number wait (optional) Max wait in ms (default 30000, max 120000)

Session lifecycle:

action What it does Returns
create Opens a new browser tab. Optionally navigates to a URL. Session ID
close Releases the tab and all its resources. Idempotent. Confirmation
list Shows all active sessions with timestamps. Session list
goto Navigates to a new URL. Page stays alive. Confirmation
wait Polls until a CSS selector exists or a JS expression returns true. Confirmation
extract Evaluates JavaScript and returns the result. Eval result
click Clicks an element by CSS selector. Coordinates
type Types text into an input field. Confirmation

Login flow example:

browse_session(action: "create", url: "https://example.com/login")
  → "Created session: session_1"

browse_session(action: "type", session_id: "session_1", selector: "#username", text: "user")
browse_session(action: "type", session_id: "session_1", selector: "#password", text: "pass")
browse_session(action: "click", session_id: "session_1", selector: "#login-btn")

browse_session(action: "wait", session_id: "session_1", selector: ".dashboard", timeout: 10000)
browse_session(action: "extract", session_id: "session_1", expression: "document.title")

browse_session(action: "close", session_id: "session_1")

Multi-article browsing example:

browse_session(action: "create")
browse_session(action: "goto", session_id: "session_1", url: "https://en.wikipedia.org/wiki/JavaScript")
browse_session(action: "extract", session_id: "session_1", expression: "document.title")
browse_session(action: "goto", session_id: "session_1", url: "https://en.wikipedia.org/wiki/Python")
browse_session(action: "extract", session_id: "session_1", expression: "document.title")
browse_session(action: "close", session_id: "session_1")

browse_scrape — parallel bulk scraping

Scrape multiple URLs simultaneously using isolated worker processes. Each URL gets its own headless browser worker — built on top of Obscura's native scrape command with obscura-worker.

Parameter Type Default Max Description
urls string[] 1000 URLs to scrape in parallel
eval string JavaScript expression to evaluate per page
concurrency number 10 100 Number of parallel worker processes
timeout number 60 300 Per-worker timeout in seconds

Example:

browse_scrape(urls: ["https://news.ycombinator.com", "https://example.com"], eval: "document.title", concurrency: 25)

Output format (JSON):

{
  "total_urls": 2,
  "concurrency": 25,
  "total_time_ms": 1250,
  "avg_time_ms": 625.0,
  "results": [
    {
      "url": "https://news.ycombinator.com",
      "title": "Hacker News",
      "eval": "Hacker News",
      "time_ms": 612,
      "worker": 0
    },
    {
      "url": "https://example.com",
      "eval": "Example Domain",
      "time_ms": 638,
      "worker": 1
    }
  ]
}

On errors (timeout, network failure, etc.), the per-URL result includes an "error" field instead of "eval":

{
  "url": "https://slow-site.com",
  "error": "timeout",
  "time_ms": 60000
}

This is the tool that directly leverages Obscura's core advantage over headless Chrome: lightweight parallel scraping with built-in stealth. The 30 MB per-worker memory footprint means 100 concurrent workers use less memory than a single Chrome instance.

Configuration

Claude Desktop / Cline / Continue / Any MCP client

{
  "mcpServers": {
    "obscura-mcp": {
      "command": "obscura-mcp",
      "args": ["--transport", "stdio"]
    }
  }
}

VS Code (Cline extension)

{
  "servers": {
    "obscura-mcp": {
      "command": "obscura-mcp",
      "args": ["--transport", "stdio"]
    }
  }
}

After global npm install, obscura-mcp is on your PATH — no absolute paths needed.

Environment Variables

Variable Default Description
OBSCURA_PATH Path to custom Obscura binary
MCP_HTTP_HOST 127.0.0.1 HTTP transport host
MCP_HTTP_PORT 3000 HTTP transport port
MCP_TRANSPORT stdio Transport mode: stdio or streamable-http
OBSCURA_STARTUP_TIMEOUT_MS 15000 Milliseconds to wait for Obscura CDP to start
OBSCURA_NAVIGATION_WAIT_MS 3000 Milliseconds to wait after page navigation
CDP_REQUEST_TIMEOUT_MS 10000 Milliseconds to wait for CDP response

Why Obscura?

  • No Chrome — pure Rust, no 200 MB browser bundle
  • CDP-native — exposes Chrome DevTools Protocol directly
  • Anti-detection — built-in stealth for scraping-resistant sites
  • Tiny footprint — ~15 MB binary, starts in milliseconds

License

MIT