Magic MCP vs Regex Safety Audit
A side-by-side look at the Magic MCP and Regex Safety Audit MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.
Verdict: choose Magic MCP for developer tools work as a local process; choose Regex Safety Audit for developer tools over a hosted endpoint. You can also run both side by side in one mcpServers block.
Which MCP server should you choose?
Choose Magic MCP when
- You need dedicated capabilities in the Developer Tools domain.
- You prefer a local stdio subprocess transport.
- Its auth model fits you: API key required.
- You have the keys it needs:
TWENTY_FIRST_API_KEY, API_KEY_21ST.
Choose Regex Safety Audit when
- You need dedicated capabilities in the Developer Tools domain.
- You prefer a remote HTTP/SSE transport.
- Its auth model fits you: No auth required.
- You want tools like
analyze_redos_risk, generate_attack_string, suggest_safe_rewrite.
Feature & specification comparison
Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Developer Tools | Developer Tools |
| Quality signal | 53/100 · Good | 51/100 · Good |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Remote HTTP/SSE |
| Auth | API key required | No auth required |
| Pricing | Paid service | Freemium |
| Required env vars | TWENTY_FIRST_API_KEYAPI_KEY_21ST | None listed |
| Verified owner | Community listing | Community listing |
| GitHub stars | 5,997 | 0 |
| Directory activity | 16 views 1 installs 0 upvotes | 0 views 0 installs 0 upvotes |
| Tools | Not listed | 3 |
| Full listing | View Magic MCP | View Regex Safety Audit |
Tools & capabilities
Magic MCP tools
No tool names declared yet. Check the project README from the listing page.
Regex Safety Audit tools 3
analyze_redos_riskFull structural analysis. Returns a risk level, every finding with its exact reason, and the JS atomic-group/generate_attack_stringFor a flagged pattern, generates candidate proof-of-concept inputs at a few sizes, plus a ready-to-run Nodesuggest_safe_rewriteConcrete rewritten pattern for the mechanically-fixable shapes; honest "no mechanical fix, here's what to change by
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.
Magic MCP
{
"mcpServers": {
"21st-dev-magic-mcp": {
"command": "npx",
"args": [
"-y",
"@21st-dev/cli@latest"
],
"env": {
"TWENTY_FIRST_API_KEY": "YOUR_TWENTY_FIRST_API_KEY_HERE",
"API_KEY_21ST": "YOUR_API_KEY_21ST_HERE"
}
}
}
}
Regex Safety Audit
{
"mcpServers": {
"regex-safety-audit": {
"url": "https://mcpize.com/mcp/regex-safety-audit-mcp"
}
}
}
Frequently asked questions
Magic MCP is categorized under Developer Tools and uses a local stdio subprocess. Regex Safety Audit belongs to Developer Tools and uses a remote HTTP/SSE transport. Pick Magic MCP for developer tools work and Regex Safety Audit 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.
Magic MCP is listed as a paid service. Auth: api key required. Regex Safety Audit is listed as freemium — a free tier with paid plans. 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 21st-dev-magic-mcp and regex-safety-audit as separate keys in the same mcpServers object, and your assistant will call tools from either one.
On AllMCPs, Magic MCP has a quality signal of 53/100 (Good) with 16 views, 1 installs and 5,997 GitHub stars. Regex Safety Audit has 51/100 (Good) with 0 views, 0 installs and 0 GitHub stars.