Australian Legislation & Caselaw MCP

Semantic legal research over primary Australian sources, with citations you can actually rely on.

An end-to-end pipeline that extracts current, in-force legislation and court decisions from official sources, parses their native structure (no OCR, no PDF scraping, no layout guessing), embeds them into local vector stores, and serves them to any MCP client — Claude, or anything else that speaks the protocol.

Every search hit carries a cite_as string with the consolidation currency date or paragraph pinpoint built in:

Work Health and Safety Act 2011 (Qld) s 175 (current as at 2026-03-29) Cromwell Corporation Ltd v ARA Real Estate Investors XXI Pte Ltd [2020] FCA 1492 [12]–[16]

Coverage

Each corpus lives in its own ChromaDB directory — independently portable (copy a folder to move a corpus), independently updatable, and re-ingestable while the others stay served. Cross-corpus search embeds the query once and fans out across the stores' HNSW indexes (~ms each), so searching everything costs about the same as searching one.

Related MCP server: mcp-context

Why the retrieval is precise

• The section is the chunk. Legislation is parsed from its structural markup — chapter/part/division/section, schedules, dictionary definitions — so retrieval returns the exact provision a lawyer would cite, with its full structural path (Part 9 > Division 3 > s 175 Power to seize evidence).

• The paragraph is the pinpoint. Modern FCA judgments number their paragraphs in the text; chunking is sequence-checked (a numbered line only opens paragraph n at last + 1), so quoted statutes can't fake a paragraph break and pinpoints like [12]–[18] are trustworthy. Where numbering genuinely isn't recoverable (old decisions, OALC's NSW text), chunks cite at case level rather than inventing pinpoints.

• Dates are part of the citation. Every legislation hit carries the reprint's currency date; the server instructs clients to cite with it. A consolidated store is not a substitute for checking amendments after that date — the tooling makes that explicit instead of hiding it.

• Definitions are first-class. Dictionary definitions become their own retrievable chunks, so "how does this Act define worker?" is a direct lookup, and one tool compares a term's definition across every instrument in the corpus.

MCP tools

Legislation (all searches take jurisdiction='qld'|'cth'|'all' and doc_type='act'|'sl'|'all'):

Caselaw (corpus='fca'|'nsw'|'all'):

Ops:

Quick start

python3 -m venv .venv && source .venv/bin/activate
pip install -e '.[mcp]'                    # extract + ingest + MCP server

# Queensland: enumerate -> download authorised XML -> embed
qld-legis enumerate --out data/manifest.json
qld-legis fetch --manifest data/manifest.json --out-dir data/xml
qld-legis-ingest data/xml --reset          # bge-m3 embeddings; --device mps on Apple silicon
qld-legis-ingest-acts data/xml             # small "which Act governs X?" triage index

qld-legis-mcp                              # stdio MCP server, ready for Claude Desktop

Claude Desktop config:

{
  "mcpServers": {
    "au-legislation": {
      "command": "/path/to/.venv/bin/qld-legis-mcp",
      "env": { "QLD_SETTINGS": "/path/to/repo/config/settings.json" }
    }
  }
}

Everything is resumable and idempotent: fetches skip existing files, ingests skip unchanged documents by content hash, and chunk ids are deterministic so re-ingesting an amended Act updates it in place.

Add the Commonwealth

qld-legis-cth enumerate      # in-force principal Acts via the FRL OData API
qld-legis-cth fetch          # compilation Epubs (resumable)
qld-legis-cth ingest         # embeds into its own collection/store

The Epub's XHTML preserves the Office of Parliamentary Counsel's drafting styles (ActHead1..5, subsection, Definition, Penalty), so Commonwealth structure parses natively too — stdlib only, no extra dependencies.

Add caselaw

qld-legis-caselaw fetch --source federal_court_of_australia --source nsw_caselaw
qld-legis-caselaw ingest                          # FCA -> its own store
qld-legis-caselaw ingest --source nsw_caselaw     # NSW -> its own store

Decisions bootstrap from the Open Australian Legal Corpus (Isaacus) — text already extracted from the courts' born-digital HTML. The multi-GB corpus file is streamed and filtered on the fly, never held in memory or stored whole. For decisions newer than OALC's last update, Isaacus's corpus creator emits the same JSONL shape, which ingest consumes unchanged.

Keeping it current

qld-legis-update                 # differential: fetch + re-embed only what changed
qld-legis-update --include-sl    # regulations too
qld-legis-update --dry-run       # show the diff first

The updater diffs the official in-force list against saved state: new documents are ingested, changed ones re-ingested (old chunks deleted first, so renumbered provisions don't linger), repealed ones removed. Byte-identical XML skips the re-embed even when the version id churns. State saves after every document, so interrupted runs resume.

Performance

• Embeddings: bge-m3 (multilingual, 1024-dim, 8k-token window). Optional ONNX int8 backend (qld-legis-export-onnx) runs queries ~4× faster on CPUs with VNNI — vectors stay compatible with a torch-built store (cosine ≥ 0.99 measured).

• Triage-first search: broad questions hit a tiny one-vector-per-instrument index before touching the full section corpus.

• Optional reranking: a cross-encoder (bge-reranker-v2-m3) re-scores top candidates when precision matters more than latency.

• Query-time embedding is one string at a time — CPU is fine for serving; no GPU needed.

Deployment

The included Dockerfile bakes the models in (starts offline; no runtime downloads) and docker-compose.yml mounts the stores as volumes:

docker compose up -d --build

To share the server, put it behind an HTTPS tunnel (Tailscale Funnel, Cloudflare Tunnel) and serve the endpoint at an unguessable path — the URL itself becomes the shared key, which suits MCP clients whose connector UI only accepts a URL:

qld-legis-mcp --http --host 127.0.0.1 --port 8000 --path "/mcp-<random>/mcp"

Bind to localhost and let the tunnel terminate TLS. QLD_MCP_TOKEN adds optional bearer-token auth for programmatic clients; QLD_MCP_ALLOWED_HOSTS re-enables Host pinning if you want it. All configuration works via env vars (QLD_DB_PATH, QLD_CTH_DB_PATH, QLD_FCA_DB_PATH, ...) or config/settings.json.

Sensible caveats

This is a research tool, not legal advice. The stores hold consolidated reprints as at their currency date — always check for amendments after the as_at date in the citation before relying on a provision. Caselaw coverage runs to the corpus's last update; verify anything decided since.

Data licensing

Redistribution of downloaded material must retain the required attributions. High Court material (not enabled by default) is personal/non-commercial only. This repository's own code is MIT.

Development

pip install -e . pytest
pytest tests/          # pure-logic tests: parsers, chunkers, diffing - no network, no ML deps

Ingest CLIs all have --dry-run modes that parse and report chunk statistics without writing anything, and the repo's source-endpoint documentation (browse-data expressions, XML rendition URLs, the QuILLS DTD walk, FRL OData quirks) lives in the module docstrings next to the code that uses it.

Roadmap

• Other state legislation (NSW/WA/SA/Tas are already in OALC with text extracted; Victoria needs its own extractor)

• NSW paragraph pinpoints via direct NSW Caselaw HTML (its pages carry proper paragraph anchors; OALC's text loses the numbering)

• High Court decisions (licence limits: personal/non-commercial)

• Point-in-time / amendment-history indexing