mcp server
capsolver-mcp
MCP Server for CapSolver — give AI agents the ability to solve CAPTCHAs (reCAPTCHA v2/v3, Cloudflare Turnstile) via the Model Context Protocol. Works with Claude, Cursor, Windsurf, and any MCP client.
Set up
Runs on your computer. Pick your agent and operating system.
Before you start
- uv (`curl -LsSf https://astral.sh/uv/install.sh | sh`)
{
"mcpServers": {
"capsolver-mcp": {
"command": "uvx",
"args": [
"capsolver-mcp"
],
"env": {
"CAPSOLVER_API_KEY": "<your CAPSOLVER_API_KEY>"
}
}
}
}same format Cursor, GitHub Copilot CLI, Junie, JetBrains AI Assistant, Augment (Auggie CLI), Factory Droid, Kiro, Devin CLI +12
Values in angle brackets are placeholders. Restart Claude Desktop after editing its config.Claude Desktop docs
README
synced Oct 17, 2026capsolver-mcp
MCP Server for CapSolver — expose captcha-solving capabilities to AI agents via the Model Context Protocol.
Published on PyPI as capsolver-mcp and listed in the official MCP Registry as io.github.capsolver-ai/capsolver-mcp.
See the capsolver-ai-hub repo for integration examples and the full documentation.
For detailed MCP client setup (Claude Desktop, Claude Code, Cursor, Windsurf, Cline, and more), see docs/mcp-integration.md.
Install
pip install capsolver-mcp
pip install capsolver-mcp[browser] # with Playwright support (for detect/solve_on_page)
All tools read the API key from the environment:
# bash / zsh
export CAPSOLVER_API_KEY="your-capsolver-api-key"
# PowerShell
$env:CAPSOLVER_API_KEY = "your-capsolver-api-key"
# cmd
set CAPSOLVER_API_KEY=your-capsolver-api-key
Usage
CLI
# stdio (default — for local MCP clients like Claude Desktop)
capsolver-mcp
# SSE (for remote / HTTP access)
capsolver-mcp --transport sse --host 0.0.0.0 --port 8000
# Streamable HTTP (MCP 2025-03-26 spec)
capsolver-mcp --transport streamable-http --host 0.0.0.0 --port 8000
CLI options
capsolver-mcp [OPTIONS]
--transport {stdio,sse,streamable-http}
Transport protocol (default: stdio)
--host HOST Bind host for SSE/HTTP transports (default: 127.0.0.1)
--port PORT Bind port for SSE/HTTP transports (default: 8000)
--api-key KEY API key (fallback: CAPSOLVER_API_KEY env)
--name NAME Server name (default: capsolver)
Programmatic
from capsolver_mcp.server import create_server
server = create_server(
api_key="your-key", # or set CAPSOLVER_API_KEY env var
server_name="capsolver", # name advertised to MCP clients
host="127.0.0.1", # bind host for SSE / HTTP transports
port=8000, # bind port for SSE / HTTP transports
)
server.run(transport="sse") # or "stdio" or "streamable-http"
Note:
hostandportare constructor parameters oncreate_server()(forwarded toFastMCP), matching the MCP Python SDK 1.x API.
Configure in Claude Desktop
Add to your claude_desktop_config.json:
{
"mcpServers": {
"capsolver": {
"command": "capsolver-mcp",
"env": {
"CAPSOLVER_API_KEY": "your-key"
}
}
}
}
To run without installing it globally, use "command": "uvx" with
"args": ["capsolver-mcp"] — this is what MCP clients generate from the
registry entry. See docs/mcp-integration.md for
per-client examples.
Available tools
| Tool | Browser? | Description |
|---|---|---|
solve_captcha | No | Solve a captcha by type + site params (token mode) |
detect_captchas | Yes | Scan a page URL and list present captcha types |
solve_on_page | Yes | Detect + solve + autofill all captchas on a page |
get_balance | No | Check account balance and packages |
get_supported_captchas | No | List all supported captcha types and handlers |
Browser-based tools (detect_captchas, solve_on_page) require the browser extra:
pip install capsolver-mcp[browser]
playwright install chromium
Development
git clone https://github.com/capsolver-ai/capsolver-mcp.git
cd capsolver-mcp
uv sync --all-extras # or: pip install -r requirements-dev.txt
uv run pytest # run tests
uv run ruff check src tests # lint
License
MIT