Extensiondev MCP vs Val Town
A side-by-side look at the Extensiondev MCP and Val Town MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.
Verdict: choose Extensiondev MCP for developer tools work as a local process; choose Val Town 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?
Choose 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.
Choose Val Town when
- You need dedicated capabilities in the Developer Tools domain.
- You prefer a local stdio subprocess transport.
Feature & specification comparison
Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Developer Tools | Developer Tools |
| Quality signal | 45/100 · Fair | 47/100 · Fair |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Local subprocess (stdio) |
| Auth | No auth required | Not declared |
| Pricing | Free | Not declared |
| Required env vars | None listed | None listed |
| Verified owner | Community listing | Community listing |
| GitHub stars | 0 | 10 |
| Directory activity | 0 views 0 installs 0 upvotes | 1 views 0 installs 0 upvotes |
| Tools | Not listed | Not listed |
| Full listing | View Extensiondev MCP | View Val Town |
Tools & capabilities
Extensiondev MCP tools
No tool names declared yet. Check the project README from the listing page.
Val Town 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": {
"mcp-291": {
"command": "npx",
"args": [
"@extension.dev/mcp"
]
}
}
}
Val Town
{
"mcpServers": {
"val-town": {
"command": "npx",
"args": [
"-y",
"@changesets/cli"
]
}
}
}
Frequently asked questions
Extensiondev MCP is categorized under Developer Tools and uses a local stdio subprocess. Val Town belongs to Developer Tools and uses a local stdio subprocess. Pick Extensiondev MCP for developer tools work and Val Town 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. Val Town has no declared pricing — check the project's own site. 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 val-town 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. Val Town has 47/100 (Fair) with 1 views, 0 installs and 10 GitHub stars.