Extensiondev MCP vs REA

A side-by-side look at the Extensiondev MCP and REA MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.

Extensiondev MCP logoExtensiondev MCPDeveloper Tools · Local subprocess (stdio)Build, run, inspect, and publish browser extensions from any MCP client. 28 tools, 11 browsers.45FairAuth: no auth requiredREA logoREADeveloper Tools · Local subprocess (stdio)Reverse engineer anything from your terminal or agent with one CLI and MCP server.56GoodAuth: no auth required

Verdict: choose Extensiondev MCP for developer tools work as a local process; choose REA for developer tools as a local process. You can also run both side by side in one mcpServers block.

Which MCP server should you choose?

Extensiondev MCP logoChoose Extensiondev MCP when

  • You need dedicated capabilities in the Developer Tools domain.
  • You prefer a local stdio subprocess transport.
  • Its auth model fits you: No auth required.
Explore Extensiondev MCP

REA logoChoose REA when

  • You need dedicated capabilities in the Developer Tools domain.
  • You prefer a local stdio subprocess transport.
  • Its auth model fits you: No auth required.
Explore REA

Feature & specification comparison

Rows where the two servers differ are marked.

SpecExtensiondev MCP logoExtensiondev MCPREA logoREA
CategoryDeveloper ToolsDeveloper Tools
Quality signal45/100 · Fair56/100 · Good
Install commandConfirmedConfirmed
TransportLocal subprocess (stdio)Local subprocess (stdio)
AuthNo auth requiredNo auth required
PricingFreeFree
Required env varsNone listedNone listed
Verified ownerCommunity listingCommunity listing
GitHub stars0385,218
Directory activity 0 views 0 installs 0 upvotes 15 views 0 installs 0 upvotes
ToolsNot listedNot listed

Tools & capabilities

Extensiondev MCP tools

No tool names declared yet. Check the project README from the listing page.

REA tools

No tool names declared yet. Check the project README from the listing page.

Ready-to-paste client configs

Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.

Extensiondev MCP

mcpServers (Claude Desktop / Cursor)
{
  "mcpServers": {
    "mcp-291": {
      "command": "npx",
      "args": [
        "@extension.dev/mcp"
      ]
    }
  }
}

REA

mcpServers (Claude Desktop / Cursor)
{
  "mcpServers": {
    "rea": {
      "command": "npx",
      "args": [
        "-y",
        "rea-agents"
      ]
    }
  }
}

Frequently asked questions

Extensiondev MCP is categorized under Developer Tools and uses a local stdio subprocess. REA belongs to Developer Tools and uses a local stdio subprocess. Pick Extensiondev MCP for developer tools work and REA for developer tools.

Copy the mcpServers block from the config section on this page into your client's config (for example claude_desktop_config.json or ~/.cursor/mcp.json), then fully restart the client.

Extensiondev MCP is listed as free. Auth: no auth required. REA is listed as free. Auth: no auth required. If a server needs environment variables such as API keys, define them under the env key in your client's MCP config.

Yes. MCP clients support multiple servers: add mcp-291 and rea as separate keys in the same mcpServers object, and your assistant will call tools from either one.

On AllMCPs, Extensiondev MCP has a quality signal of 45/100 (Fair) with 0 views, 0 installs and 0 GitHub stars. REA has 56/100 (Good) with 15 views, 0 installs and 385,218 GitHub stars.