mcp-server

The MCP server for abap2UI5 — gives any AI coding agent (Claude Code, Cursor, VS Code Copilot, or any MCP client) the full abap2UI5 development loop, without an SAP system:

examples -> app_guide -> validate_view + screenshot_view -> deploy_app -> build_backend -> run_app -> pitfalls
(has somebody  (how an app  (SECONDS, no system:        (write ABAP,  (transpile      (boot headless,  (what a green
 built it       is built)    is the view legal,          lint)         to Node)        errors +         run still
 already?)                   and what does it LOOK like)                               SCREENSHOT)      does not prove)

The agent writes an ABAP class, validates the view and looks at a picture of it in seconds, deploys it, boots it in a real browser and looks at the running app — then iterates. Everything runs locally on infrastructure that already guards the abap2UI5 ecosystem in CI: the abaplint transpiler + open-abap runtime, the framework's express shim, the samples-controls build and boot gates, and the linter validation core.

Documentation

→ The MCP server, in full — what MCP means here, the three setup levels and what each one buys, how to register the server with your client, every tool with what the agent gets from it, and the loop they are meant to be used in.

→ Building with AI — the whole AI setup in rising order of effort. This server is the top rung; the cheaper ones matter first.

Related MCP server: @ui5/mcp-server

Quick start

Level 1 — validate_view and screenshot_view, the two tools most work happens at (~3 MB, a minute):

git clone https://github.com/abap2UI5/linter        # AI_VIEW_CHECK_HOME
cd linter && npm ci

The server itself is on npm, so it needs no checkout. Register it with Claude Code:

claude mcp add abap2ui5 -- npx --yes @abap2ui5/mcp-server

(The install is ~45 MB, 19 MB of it a Playwright driver only run_app uses — paid on the first start, cached after. From a checkout instead: git clone https://github.com/abap2UI5/mcp-server && cd mcp-server && npm ci, then claude mcp add abap2ui5 -- node /path/to/mcp-server/server.mjs.)

Cursor, VS Code and Claude Desktop take the standard stdio shape — the documentation has the JSON, and the two further levels (the sample catalogues and deploying, then the headless build-and-boot loop). A tool whose prerequisites are missing answers with a message naming what it needs; the server starts either way.

The abap2UI5 VS Code extension registers this server for you, and adds a second one of its own for the tools that need a real SAP system.

Tools

Every tool reads live from a sibling checkout, and each one needs a specific sibling — there is no "optional" repository, only tools you do or do not use. The Needs column says which checkout a tool is dead without: the linter alone carries validate_view and screenshot_view (the fast loop, where most iterations happen), the framework checkout carries the guide, the pitfalls and the backend, and the corpus carries almost everything else. A tool whose checkout is missing answers with the clone command and env var that fix it.

examples degrades per catalogue instead of failing: it searches the checkouts it finds and names the ones it could not, so a thinner answer never reads as "nobody has built this". It reads each repository's committed catalogue.json where the checkout has one — which is what carries a control port's verification status (checked over reviewed over generated, used to break ranking ties), the learning-path stage, and what a stack sample needs from the system — and falls back to parsing SAMPLES.md on a checkout from before that file existed. screenshot_view and run_app answer the same question at three orders of magnitude apart: the first photographs the reconstructed view with no backend, the second the running app after a build. Most iterations should end at the first.

Resources

The knowledge documents behind those tools are also MCP resources, for clients that surface them (context pickers, attach-a-document UIs) and for agents that want a document whole instead of sliced. Same live reads from the same sibling checkouts: listing is free (no checkout needed), reading a resource whose checkout is missing answers with the same actionable error the tool gives.

Prompts

Two prompts — one per job this server serves — put an agent straight into the loop instead of leaving it to reconstruct the order from sixteen tool descriptions. Each renders an orchestration script over the tools above and duplicates none of their content:

• build-an-abap2ui5-app (argument: task, what the app should do) — orient with examples/capabilities, learn the shape from app_guide, write the class, iterate through validate_view/screenshot_view in seconds, prove it with deploy_app → build_backend → run_app, close with pitfalls.

• port-a-ui5-sample (argument: sample, the demo-kit sample) — the corpus job: generation_rules as the brief, scope_of and capabilities before writing, neighbouring ports from examples, then the same validate/screenshot/deploy/run loop.

Notes

• Dev sandbox: deployed apps land in the samples-controls checkout's gitignored src/zz_dev/ — nothing an agent deploys can leak into a commit.

• Port: the backend listens on 3000 (A2UI5_MCP_PORT overrides).

• Timeouts: every spawned child is killed (whole process tree) when it exceeds its limit — lint/scope 5 min, build 30 min by default; A2UI5_MCP_LINT_TIMEOUT_MS, A2UI5_MCP_SCOPE_TIMEOUT_MS and A2UI5_MCP_BUILD_TIMEOUT_MS override (values in ms).

• UI5 sources are served from the samples-controls checkout's @openui5 packages, so booting needs no network. The built theme CSS is not in those packages — with network access it loads from the CDN (styled screenshots); without, apps render unstyled but structurally complete. A2UI5_MCP_OFFLINE=1 forces the hermetic behaviour.

• Chromium: uses the Playwright-managed browser; if absent, falls back to a system chromium (A2UI5_MCP_CHROMIUM overrides the executable path).

• If you set this up earlier: the corpus repository was ai-demokit, then abap2UI5-api, and is samples-controls today. Nothing needs changing — an existing checkout is still found under any of the three directory names, and AI_DEMOKIT_HOME is still read alongside SAMPLES_CONTROLS_HOME.

• Real-system deployment stays what it is today: abapGit. This server is the inner dev loop; the real-system half lives in the VS Code extension, whose own MCP server exposes it as run_app_on_system. Both servers are registered in the same editor window, which is why that tool is not called run_app.

Working on this repository

npm ci
npm test

AGENTS.md carries the conventions, CONTRIBUTING.md and RELEASING.md the rest of the workflow.