# Let Your AI Agent Scaffold Apps With seed4j-mcp > Source: > Published: 2026-05-18 20:51:07+00:00 If you've ever bootstrapped a Spring Boot + Vue project by hand, you know the routine: pick a build tool, glue in a frontend, add JPA, choose a database driver, wire Liquibase, remember the Maven wrapper, look up that one annotation for the seventh time this year. By the time you reach `initial commit` , half your motivation is gone. [seed4j](https://github.com/seed4j) already solves most of that. It's an open source application generator that applies *modules* to a project folder — click click click, project done. But seed4j is still a tool **a human drives**. You read the docs, you pick the module slugs, you remember whether the property is `packageName` or `basePackage` this release. Fine, but not exactly thrilling. [ seed4j-mcp](https://github.com/avdev4j/seed4j-mcp) is a [Model Context Protocol](https://modelcontextprotocol.io)server that hands seed4j to your AI agent instead. Plug it into Claude Code, Claude Desktop, or Cursor, and the agent can: - browse the seed4j catalog, - pick a coherent stack, - validate properties before applying anything, - and scaffold a project end to end. You stay in the conversation. The agent does the orchestration. Heads up — this is an alpha.`seed4j-mcp` is a fresh first release. The tool surface, defaults, and behavior may change as feedback comes in. It's stable enough to play with, but don't wire it into anything critical yet. Bug reports and suggestions are very welcome. ## How the pieces fit together `seed4j-mcp` is intentionally thin. Three components: - **A running seed4j instance**— the actual generator, reachable over HTTP (default`http://localhost:1339` ). - — a Node.js MCP server that translates MCP tool calls into seed4j REST calls.`seed4j-mcp` - **Your MCP client**— Claude Code, Claude Desktop, Cursor, etc., speaking MCP over STDIO to`seed4j-mcp` . ``` [Claude Code] ⇄ STDIO ⇄ [seed4j-mcp] ⇄ HTTP ⇄ [seed4j server] ``` That separation matters: `seed4j-mcp` does not embed seed4j as a library. It's a translator. seed4j can evolve on its own and the MCP server keeps doing its job — no version-pinning gymnastics. One implementation detail worth knowing: `seed4j-mcp` speaks MCP over **STDIO**. The MCP framing lives on stdout, which means anything else writing to stdout will corrupt the stream and your MCP client will hang. The server routes its startup errors to stderr for that reason. If you fork the project and add logging, use `console.error` or write to a file — never `console.log` . ## Tutorial ### Prerequisites Three things on your machine: - **Node.js 20+**—`seed4j-mcp` ships as an npm package and runs under Node (yes, even if you're a Java person). - **A running seed4j instance**— see the[seed4j docs](https://github.com/seed4j)for how to start one. Default URL:`http://localhost:1339` . - **An MCP-aware client**— I'll use[Claude Code](https://claude.com/claude-code), but Claude Desktop and Cursor work the same way. Quick sanity checks: ``` node --version # v20.x or newer curl http://localhost:1339/api/modules | head -c 200 ``` If the curl call returns JSON, you're ready. ### Getting started You don't need to install `seed4j-mcp` globally. The package is published on npm and the recommended pattern is to let your MCP client launch it on demand via `npx` . First run pulls it down, later runs use the cache. If you'd rather install it globally: ``` npm install -g seed4j-mcp ``` Or build from source if you want to contribute: ``` git clone https://github.com/avdev4j/seed4j-mcp.git cd seed4j-mcp npm install npm run build ``` ### Run it with Claude Code Claude Code has an `mcp` subcommand built for exactly this. Pick a scope based on how widely you want the server available: ``` # Local: just you, this project (default scope) claude mcp add seed4j -- npx -y seed4j-mcp # Project: committed to .mcp.json, shared with collaborators claude mcp add seed4j --scope project -- npx -y seed4j-mcp # User: available across all your projects on this machine claude mcp add seed4j --scope user -- npx -y seed4j-mcp ``` Running seed4j on a non-default URL? Pass it as an env var: ``` claude mcp add seed4j --env SEED4J_BASE_URL=http://localhost:7471 -- npx -y seed4j-mcp ``` Verify the server is wired up: ``` claude mcp list ``` Restart Claude Code and the tools become available to the agent automatically. ### Run it with Claude Desktop or Cursor Both clients read a JSON config. Add an entry pointing at the npx entrypoint: ``` { "mcpServers": { "seed4j": { "command": "npx", "args": ["-y", "seed4j-mcp"], "env": { "SEED4J_BASE_URL": "http://localhost:1339" } } } } ``` Restart the client and you're done. ## Example usages The real test is what the agent does once the tools are available. A few prompts that exercise different flows. ### 1. "Scaffold a Spring Boot + Vue webapp" The **curated stack** path. You name the vibe, the agent picks a preset. Under the hood it will: - Call `list_presets` to see what's on offer. - Pick the one that matches (e.g. *"Webapp: Vue + Spring Boot"*). - Call `get_preset_details` for the ordered module list. - Call `create_project` to initialize the folder. - Call `apply_preset` to apply every module in order with a shared property map. Your prompt is one line: Scaffold a new project at `/tmp/my-webapp` using a Vue + Spring Boot preset. Use`com.example.webapp` as the Java package and`mywebapp` as the base name. ### 2. "I want a custom stack, not a preset" The **custom stack** path. The agent will: - `search_modules` to find candidates matching your description. - `get_module_dependencies` to learn the prerequisite ordering and any feature choices (yes, you have to pick a datasource flavor — the agent won't guess for you). - `validate_properties` to dry-run the property map before touching the filesystem. - `apply_modules` to apply the full ordered list in one batch, stopping at the first failure. Example prompt: Create a Java library project at `/tmp/my-lib` with Maven, Jacoco, and SonarQube wired up. Package`com.example.lib` . ### 3. "What's already in this project?" When the folder exists, `get_project_status` tells the agent which modules have been applied and what properties are in play — so it suggests sensible next steps instead of stomping over existing state: Look at `/tmp/my-webapp` and tell me what's wired up. What would you suggest adding next? ### 4. "Show me the catalog" You can also use the agent as a guided browser. It will reach for `search_modules` and `get_module_details` and summarize the catalog: What persistence modules does seed4j support? Compare Postgres, MySQL, and MongoDB options. ## Available tools The agent gets a small but expressive toolbox covering module discovery, preset lookup, property validation, and project application. Rather than reproducing the full list here (and watching it drift the next time a tool is added), check the up-to-date catalog directly in the repo: The README lists every tool with the description the agent actually sees. ## See it in action If you'd like to see what a project scaffolded through `seed4j-mcp` actually looks like, here's one I generated: It's the output of a real agent session — useful as a reference for the kind of structure, files, and module combination you can expect when you hand the wheel to your AI agent. ## Wrapping up Application generators have always traded flexibility for speed: faster than handcrafting, less flexible than writing it yourself. Putting an LLM in front of one tips the balance — the agent handles orchestration, and you stay at the level of *"build me a Java library with Jacoco and SonarQube"*. No memorizing slugs, no fighting property names. And the scaffolded project isn't a dead drop. seed4j writes a `documentation/` folder alongside the code with the conventions, code style, and recommendations specific to the modules you applied. That folder is a goldmine for the *next* step: pointing your AI agent at it while you write the business code keeps the generated structure and the hand-written code coherent — same package layout, same patterns, same style — instead of the usual drift between bootstrapped scaffolding and the features you add on top. `seed4j-mcp` is Apache 2.0. Source at [github.com/avdev4j/seed4j-mcp](https://github.com/avdev4j/seed4j-mcp), published on npm as [ seed4j-mcp](https://www.npmjs.com/package/seed4j-mcp). Issues, PRs, and creative stack requests welcome. If you ship something with it, I'd love to see it.