hadith-mcp

Model Context Protocol (MCP) server and data pipeline for serving canonical hadith text (Arabic and English) to assistants in a citation-safe way—similar in spirit to quran-mcp: fetch from a real corpus instead of quoting from model memory.

This repository provides a FastMCP server over data/hadith.db plus a data pipeline to build that database: normalized SQLite, OpenAI embeddings (text-embedding-3-large), cross-collection references (cosine similarity + narrator-aware scoring), and provenance-style tags (e.g. muttafaq-style links between Sahih al-Bukhari and Sahih Muslim).

Data sources and credits

• Hadith text comes from the community hadith-json dataset (scraped from Sunnah.com), which aligns with the broader sunnah-com / Quran Foundation ecosystem—the same family of sources behind quran-mcp.
• Architecture and patterns are inspired by quran-mcp (FastMCP, grounding mindset, tooling layout).

If you ship a product or paper, keep upstream attribution visible (dataset authors, Sunnah.com, and the scholarly collections themselves).

Repository layout

Large reference trees hadith-json-main/ and quran-mcp-master/ are listed in .gitignore. Clone or unpack hadith-json locally (for example as hadith-json-main/) or pass --data-dir to build_db.py.

Quick start

python3 -m venv .venv
source .venv/bin/activate
pip install -e ".[dev]"
cp .env.example .env   # set OPENAI_API_KEY for embedding steps

1) Build the database (without calling OpenAI)

Point --data-dir at your local hadith-json db/by_book directory.

python scripts/build_db.py --fresh --skip-embed --skip-cross --skip-provenance \
  --data-dir ./hadith-json-main/db/by_book

2) Embeddings (long run; use a separate machine if you prefer)

Safe defaults: batch size 1, commit every 10 rows, sleep between calls, optional JSONL checkpoint for safety.

python scripts/embed_hadith.py \
  --db-path ./data/hadith.db \
  --checkpoint ./data/embeddings_checkpoint.jsonl \
  --batch-size 1 \
  --commit-every 10 \
  --sleep-between-batches 0.15

Replay checkpoints into the DB when needed:

python scripts/merge_embedding_checkpoints.py --db-path ./data/hadith.db \
  ./data/embeddings_checkpoint.jsonl --only-missing

3) Cross-references and provenance (local CPU)

Do not re-run build_db.py without --fresh after embedding unless you intend to re-import JSON (that path can overwrite rows and clear embedding). Instead:

python scripts/compute_crossref.py --db-path ./data/hadith.db

For a single-machine full build (import + embed + cross + provenance), run build_db.py once without --skip-embed / --skip-cross / --skip-provenance, and pass embedding pacing flags as needed (python scripts/build_db.py --help).

4) MCP server (stdio for Cursor / Claude Desktop)

From the repo root with data/hadith.db present (or set HADITH_MCP_DB_PATH):

hadith-mcp --transport stdio
# or: python -m hadith_mcp --transport stdio
# or: fastmcp run hadith_mcp.server:mcp

Optional --config config.yml sets database.path relative to the config file. HADITH_MCP_DB_PATH overrides both.

HTTP / SSE / streamable HTTP (see FastMCP docs for host/port env vars):

hadith-mcp --transport http

Tools (summary): fetch_grounding_rules returns full text once per MCP session (then a short repeat unless force_full=True); pass returned nonce only when you need to disambiguate errors. fetch_hadith accepts global hadith_id or collection + hadith_number (int, or string range like 1-5) with optional include_cross_references. The collection argument is resolved through a forgiving slug matcher — canonical slugs (bukhari), common variants (sahih-bukhari, Sahih al-Bukhari, sahih_bukhari), and human names (Sunan Abu Dawud, Musnad Ahmad, 40 Hadith Nawawi) all map to the same row. search_hadith defaults to semantic search (loads all embeddings at startup, embeds the query with the configured query embedding model); use mode=keyword for SQL substring search, or mode=both. Semantic search needs OPENAI_API_KEY and a database whose rows include embeddings. If OpenAI returns quota/billing/rate-limit errors (or the query vector size does not match the DB), the server falls back to keyword search instead of failing. fetch_cross_references returns algorithmic similarity matches across collections for a given hadith. show_hadith opens an interactive Hadith Reader MCP App in supported hosts (ChatGPT Developer Apps, Claude with app support, etc.); prefer calling it with the canonical hadith_id returned by fetch_hadith / search_hadith / fetch_cross_references — collection + hadith_number and free-text query are supported fallbacks, and the tool always returns a plain-text fallback so non-App hosts still get a readable answer with the same citation URLs. The top-level MCP instructions nudge assistants toward the two-step flow (look up first, then show_hadith(hadith_id=…)) to avoid guessing slugs or numbers from memory. Optional per-client rate limits and an LRU query cache reduce cost and abuse (see config.yml / .env.example).

Citation URLs. fetch_hadith, search_hadith, fetch_cross_references, and show_hadith attach a url field to each hadith or cross-reference row pointing at the search frontend (https://search.hadith-mcp.org/?id=<db_id> by default, overridable via HADITH_SEARCH_APP_URL). The server's MCP instructions tell assistants to always surface this link alongside citations and to never fabricate links to external hadith sites (sunnah.com, etc.).

Interactive reader (show_hadith). The tool binds to a ui://hadith.html resource served as text/html;profile=mcp-app. The HTML template lives at src/hadith_mcp/assets/hadith_app.html and is fully self-contained — inline CSS, inline app logic, system fonts only, zero CDN fetches, zero cross-origin iframes. The @modelcontextprotocol/ext-apps SDK is vendored under src/hadith_mcp/assets/ext-apps.bundle.js (rewritten to a classic script that attaches to window.__hadithMcpSdk) and spliced into the template at startup, so the whole widget ships as a single HTML document. Refresh the pinned SDK version with python3 scripts/fetch_ext_apps.py --version <x.y.z>. The resource meta sets ui.csp.resourceDomains = [] (no external origins at runtime) and intentionally omits ui.domain because ChatGPT and Claude require incompatible formats for that field (ChatGPT wants any https://… URL; Claude requires a sha256-derived *.claudemcpcontent.com subdomain and errors with "App domain configuration is invalid" on anything else) — both hosts work correctly when the field is omitted. Once mounted, the embedded app calls fetch_hadith and search_hadith over the MCP bridge (no extra HTTPS) to let users open cross-references and switch between detail and search views without LLM round-trips. A single-hadith show_hadith call renders pure card chrome (no search bar); calls with a query or no arguments render the search-bar + results UI.

5) Public search frontend and REST API

The repo ships a small static search app in search/ and an HTTP REST surface on the same FastMCP process, intended to be deployed as two subdomains (e.g. search.hadith-mcp.org and api.hadith-mcp.org) with nginx / Caddy proxying /api/* to the FastMCP port.

• Frontend (search/): plain HTML/CSS/JS, no build step. Bootstraps from ?id=<db_id> or ?q=<query> on load, so the URLs MCP tools emit resolve directly. The API base defaults to https://api.hadith-mcp.org; override in the browser via window.HADITH_API_BASE (set before script.js loads) for local or staging deployments. search/sitemap.xml is a sitemap index; per-collection URL lists live under search/sitemaps/ — regenerate with python3 scripts/generate_search_sitemap.py after rebuilding the database.
• REST endpoints (same process, mounted via @mcp.custom_route):
  • GET /api/collections → {collections: [...]}
  • GET /api/hadith/{hadith_id} → {hadith: {...}}
  • GET /api/hadith/{slug}/{id_in_book} → {hadith: {...}}
  • GET /api/search?q=&limit=&collection= → {results, mode, note}; semantic by default with the same keyword fallback behavior as the MCP tool. Shares HADITH_MCP_RATE_LIMIT_SEARCH_RPM and the query cache with MCP clients, so one budget covers both surfaces.
  • GET /api/stats (optional trailing slash) → aggregate search/lookup counts, unique visitors, uptime. Landing + search UIs try same-origin GET /api/stats first, then the public API host; re-copy site/ and search/ when you update those pages, or the browser will run old HTML/JS.

Configuration

• Secrets: .env is gitignored; see .env.example for OPENAI_API_KEY and MCP tuning (HADITH_MCP_QUERY_EMBEDDING_MODEL, HADITH_MCP_RATE_LIMIT_SEARCH_RPM, HADITH_MCP_SEARCH_CACHE_MAX).
• Hosted MCP: Put OPENAI_API_KEY on the server only if you accept paying for query embeddings; tune HADITH_MCP_RATE_LIMIT_SEARCH_RPM (e.g. 30–120) and cache size. The query model must match the dimension of vectors stored in hadith.db (this repo’s build uses text-embedding-3-large / 3072). A cheaper OpenAI model generally means rebuilding the database with that model so dimensions align.
• Artifacts: Other data/*.db files and embedding checkpoint globs are gitignored; this repo tracks data/hadith.db (Git LFS) plus data/SHA256SUMS for verification (cd data && sha256sum -c SHA256SUMS).
• Embeddings: Rows with empty English narrator and text still embed using Arabic text when present. Long inputs are clipped with tiktoken (cl100k_base) to stay under the 8192-token API limit, with a further shrink ladder if a row still hits length errors.
• Count rows without the sqlite3 CLI:
  python -c "import sqlite3; c=sqlite3.connect('data/hadith.db'); print(c.execute('SELECT COUNT(*) FROM hadiths WHERE embedding IS NULL').fetchone()[0])"

License

• Software in this repository (Python, scripts, and documentation we added) is licensed under GNU General Public License v3.0 only (SPDX: GPL-3.0-only).
• Hadith text and other upstream material remain under their original terms (hadith-json, Sunnah.com). Our GPL applies to our code, not to a relicensing of that content; keep attribution and follow upstream rules when you redistribute data or excerpts.

Releases and data integrity

• Checksum: data/SHA256SUMS lists hadith.db. After cloning or downloading the database, run cd data && sha256sum -c SHA256SUMS.
• Signing (optional): A detached GPG or Sigstore signature over the checksum file or the database proves who published the bytes and that they were not altered afterward. Signing does not certify scholarly accuracy of every narration or automated cross-reference.
• Reproducibility: For audits or rebuilds, record the hadith-json revision, this repo’s git revision, the embedding model id, and script versions you used.