Magic MCP vs Endiagram MCP
A side-by-side look at the Magic MCP and Endiagram MCP 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 Endiagram MCP 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 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 Endiagram 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.
- You have the keys it needs:
EN_API_URL, ENDIAGRAM_TELEMETRY. - You want tools like
structure, invariant, live.
Feature & specification comparison
Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Developer Tools | Developer Tools |
| Quality signal | 53/100 · Good | 61/100 · Good |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Local subprocess (stdio) |
| Auth | API key required | No auth required |
| Pricing | Paid service | Free |
| Required env vars | TWENTY_FIRST_API_KEYAPI_KEY_21ST |
Tools & capabilities
Magic MCP tools
No tool names declared yet. Check the project README from the listing page.
Endiagram MCP tools 7
structureWhat is this system? Returns shape (Pipeline, Fork-Join, DAG, Star, Cycle, Tree, Complete, etc.), stages with roles, bridge nodes, cycles, parallelism, critical path, dominator tree, min-cuts, subsystems, interface nodes, actors (who does what, workload entropy), locations (where work happens, boundary crossings). Levers: node=X returns per-node centrality (betweenness, closeness, eigenvector) for a specific node. detect_findings=true flags named structural risks — unguarded-sink (sinks reachable via only pipeline actions, no JOIN/HUB gating), single-cut-path (source-sink pairs with only one vertex-disjoint path), multi-cut-path (paths with redundant defense, min-cut > 1). See server instructions for EN language syntax.invariantWhat's always true — automatic findings and on-demand checks. Automatic outputs: conservationLaws (weighted entity sums constant across executions), sustainableCycles (T-invariants — action sequences returning to start state), depletableSets (entity groups whose simultaneous depletion is irreversible), behavioral.deficiency (0 means structure fully determines dynamics), behavioral.isReversible, behavioral.hasUniqueEquilibrium. On-demand via `rules`: encode domain-specific claims and verify them against the graph — this is how to check things the topology alone can't see (precedence, coverage, centrality bounds, resilience). See the rules parameter for supported sentence shapes.liveCan it deadlock? Can entities overflow? isStructurallyLive means every siphon contains a trap — no structural deadlock possible. uncoveredSiphons are entity groups that can drain permanently, with the actors and locations affected. isStructurallyBounded means no entity can accumulate without limit. unboundedCycles are action sequences that could cause overflow. See the server instructions for EN language syntax.reachableCan X reach Y? Follows directed data flow first; falls back to undirected. `from` and `to` accept entity names or action names (resolved against the program). Path shows each step with actor and location. locationCrossings counts boundary transitions. defense_nodes checks if guards cover all paths; coverage.fullCoverage=false means unguarded routes exist. See the server instructions for EN language syntax.
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"
}
}
}
}
Endiagram MCP
{
"mcpServers": {
"endiagram-mcp": {
"command": "npx",
"args": [
"-y",
"@endiagram/mcp"
],
"env": {
"EN_API_URL": "YOUR_EN_API_URL_HERE",
"ENDIAGRAM_TELEMETRY": "YOUR_ENDIAGRAM_TELEMETRY_HERE"
}
}
}
}
Frequently asked questions
Magic MCP is categorized under Developer Tools and uses a local stdio subprocess. Endiagram MCP belongs to Developer Tools and uses a local stdio subprocess. Pick Magic MCP for developer tools work and Endiagram MCP 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. Endiagram MCP 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 21st-dev-magic-mcp and endiagram-mcp 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. Endiagram MCP has 61/100 (Good) with 3 views, 0 installs and 8 GitHub stars.