mcp-fact-finder 0.1.2

Semantic fact indexer over markdown knowledge bases — extracts atomic facts, entities, and authority scores, then exposes search via MCP

mcp-fact-finder

Semantic fact indexer over markdown knowledge bases.

Crawls markdown documents, extracts atomic facts using local NLP (free, no API key) or an optional LLM enrichment pass, stores facts in LanceDB with authority scoring and entity relationships, and exposes structured search via the Model Context Protocol.

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Why local inference?

Pass 1 (rebel-large NLP) is completely free.

No API keys, no rate limits, no cost. Runs locally on CPU or Apple Silicon MPS (Metal Performance Shaders). A full 7,600-document knowledge base indexes in ~5 hours at $0.

Pass 2 (LLM enrichment) is optional. It adds canonical fact forms, tense classification, and better entity linking. Use a local Ollama instance (free) or OpenRouter (~$5–9 for 7,600 docs).

Recommendation: Run Pass 1 first. For most knowledge bases, Pass 1 alone is sufficient for useful search results.

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Status: v0.0.3

Component	Status
Data models	✅ Complete
Markdown crawler	✅ Complete
Authority scoring	✅ Complete
rebel-large extractor	✅ Complete
Ollama extractor	✅ Complete
OpenRouter/Bedrock	✅ Complete
Embedder (bge-small)	✅ Complete
LanceDB store	✅ Complete
MCP server (6 tools)	✅ Complete
Inconsistency checker	✅ Complete
Indexing pipeline	✅ Complete
Setup script	✅ Complete

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Quick start

1. Install

pip install mcp-fact-finder
# or
uv add mcp-fact-finder

Or clone and develop locally:

git clone https://github.com/bobmatnyc/mcp-fact-finder
cd mcp-fact-finder
uv sync

2. Index your knowledge base (Pass 1 — free, no API key needed)

# Index a directory of markdown files
uv run scripts/index.py --path ~/my-docs/

# First 100 docs only (quick smoke test)
uv run scripts/index.py --path ~/my-docs/ --limit 100

# Show current stats
uv run scripts/index.py --path ~/my-docs/ --stats

The index is stored in {path}/.mcp-fact-finder/db — co-located with your docs, trivial to delete and rebuild. Incremental re-runs only process new or changed files (content-hash based — moving a file does not trigger reindexing).

3. Set up Claude Code MCP integration

# In the project you want to query:
cd ~/my-project
uv run --project ~/Projects/mcp-fact-finder scripts/setup.py

Creates .mcp.json (Claude Code MCP config) and .claude/skills/mcp-fact-finder.md (explains when/how to use each tool), then adds .mcp-fact-finder/ to .gitignore. Restart Claude Code to activate.

4. Optional: LLM enrichment (Pass 2)

# Via local Ollama (free, no API key):
FACT_FINDER_INFERENCE_BACKEND=ollama \
uv run scripts/index.py --path ~/my-docs/ --pass 2 --force

# Via OpenRouter (~$5-9 for 7,600 docs):
FACT_FINDER_OPENROUTER_API_KEY=sk-... \
uv run scripts/index.py --path ~/my-docs/ --pass 2 --force --workers 150

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MCP Tools

Six tools are exposed to Claude Code once the index is running:

Tool	Description
search_facts	Natural language semantic + keyword search, authority-ranked
get_document_facts	All facts extracted from one source document
compare_sources	How different docs describe the same topic
get_entity_facts	All facts about a named entity (person, system, concept)
check_inconsistencies	Contradictions and conflicts for an entity
get_conflict_report	Detailed explanation of a specific pair inconsistency

Example queries

"What was decided about the Pricerator architecture?"
→ search_facts(query="Pricerator architecture", fact_type="decided", min_authority=0.8)

"What do all documents say about latency?"
→ compare_sources(topic="P90 latency")

"Everything known about Thomas Evans"
→ get_entity_facts(entity="Thomas Evans")

"Are there contradictions about the GCP migration?"
→ check_inconsistencies(entity="GCP migration")

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Authority scoring

Facts are ranked by source document type × recency × LLM confidence:

Score	Document type
1.0	Technical specs, RFCs, ADRs, TDDs
0.8	Product requirements (PRDs)
0.5	Meeting notes, retros, sprint notes
0.3	Summaries, digests, inferred content

Use min_authority: 0.8 to restrict results to high-confidence sources.

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Fact types

Type	Pattern	Example
is	X is / has Y	"Pricerator is the pricing engine"
said	X stated / believes	"Thomas said the migration was overdue"
happened	X occurred (past)	"GCP migration completed Q3 2024"
planned	X will / intends	"Team plans to deprecate the monolith"
decided	It was decided	"Team decided to use LanceDB"
metric	X = N (quantified)	"P90 latency is 340ms"

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Architecture

Markdown files
    │
    ▼
Crawler (discover_documents)
  • Confluence / YAML frontmatter parsing
  • Authority tier from filename keywords
  • Content-hash document identity (stable across moves)
    │
    ▼
Pass 1: rebel-large NLP  [FREE — local CPU/MPS]
  • Relation extraction (SPO triples)
  • ~20 docs/min on Apple M-series
    │   (optional)
    ▼
Pass 2: LLM enrichment  [Ollama local = free | OpenRouter ~$5–9]
  • Canonical fact forms + tense + fact_type
  • Better entity linking
    │
    ▼
LanceDB  (vector + FTS hybrid search)
  • facts, entities, documents, inconsistencies tables
    │
    ▼
MCP Server  (stdio transport, Claude Code)
  • 6 structured search tools

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Environment variables

Variable	Default	Description
FACT_FINDER_DB_PATH	{corpus}/.mcp-fact-finder/db	LanceDB path
FACT_FINDER_INFERENCE_BACKEND	rebel	rebel | ollama | openrouter | bedrock
FACT_FINDER_OPENROUTER_API_KEY	—	OpenRouter key (Pass 2)
FACT_FINDER_OPENROUTER_MODEL_ID	google/gemini-2.0-flash-lite-001	Pass 2 model
FACT_FINDER_BEDROCK_REGION	us-east-1	AWS Bedrock region

Copy .env.example to .env and fill in as needed.

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Development

uv run pytest          # run tests
uv run ruff check src/ # lint
uv run mypy src/       # type check

make build             # build wheel + sdist
make publish           # bump patch, publish to PyPI, tag, push
make publish-minor     # bump minor version

See docs/architecture.md for the full design document.

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License

Proprietary. See LICENSE.