EU MAR MCP

An open-source Model Context Protocol server for the EU Market Abuse Regulation. It gives AI assistants such as Claude the text of MAR, its delegated and implementing acts and ESMA's guidance — linked article by article, so that asking about a provision also brings up the Level 2 rules that supplement it and how ESMA interprets it. For energy and commodity firms it also maps MAR to REMIT.

Not legal advice. ESMA guidelines and Q&As are not legislation. Texts are as of the fetch date returned with every answer; check the linked source.

Companion to REMIT MCP, which serves REMIT and ACER's guidance. The two servers are meant to be connected side by side.

What it covers

Every act is fetched in its latest consolidated version where one exists. Sources are fetched from EUR-Lex (Publications Office CELLAR) and esma.europa.eu every day.

Related MCP server: compass-mcp

Tools

Citations it understands: Article 17 MAR, Article 17(4) MAR, Art. 7 of the Market Abuse Regulation, Recital 23 MAR, Article 2 2016/957, Article 4 CS MAD, ESMA Q&A 5.1, delay guidelines 5.1.

How it works

The pipeline is the one used by REMIT MCP:

• Parsing. EUR-Lex acts are split into recitals, articles and annexes from their XHTML. ESMA PDFs are read line by line with font metadata (scripts/pdf_lines.py); sections are recovered from typography and ESMA's numbering. In the Q&As every question ("Q5.1", "Question 5.1") becomes a unit whose title is the question and whose text is the answer; withdrawn questions are dropped. Guidelines are split at their numbered paragraphs.

• Linking. Every unit is scanned for references such as "Article 17(4) of MAR", "Article 16(2) of Regulation (EU) No 596/2014" or "Article 2 of Commission Delegated Regulation (EU) 2016/957"; these links drive get_provision.

• Search. BM25 over titles and text, fused with semantic search (Cloudflare Workers AI embeddings and Vectorize) when available; BM25 alone otherwise.

• Domain lexicon (src/lexicon.mjs): STOR ↔ suspicious transaction and order report, PDMR ↔ person discharging managerial responsibilities, closed period ↔ blackout period, market sounding ↔ wall-crossing, and so on.

• Crosswalk (src/crosswalk.mjs): written by hand. The REMIT side was checked against the consolidated REMIT text (CELEX 02011R1227-20250205).

Status

Version 0.1.0. The code runs on fixture data (npm test without fetched sources runs test/fixture.test.mjs); the first run of the deploy workflow fetches the real sources. After that run, check the fetch log in the workflow summary: ESMA PDF URLs are discovered from ESMA's pages and may need adjusting in scripts/sources.mjs, and the Q&A parser should be checked against the real document. There is no search evaluation set yet.

Use

Local:

git fetch origin sources && git worktree add .sources origin/sources   # fetched documents
pip install pdfplumber                                                  # PDF text extraction
npm test        # builds data/mar.json and runs the tests
npm run dev     # http://localhost:8787/mcp

Deployment: the GitHub Actions workflow (.github/workflows/deploy.yml) fetches, builds, tests and deploys to Cloudflare Workers. It needs the repository secrets CLOUDFLARE_API_TOKEN and CLOUDFLARE_ACCOUNT_ID.

Licence

Code: Apache-2.0. EU legislation is reused under the Commission's reuse policy (Decision 2011/833/EU); EUR-Lex is the authentic source only for the Official Journal. ESMA documents: check ESMA's reuse conditions before publishing; every answer names and links its source.