entroly 0.4.2

Information-theoretic context optimization for AI coding agents. Knapsack-optimal token budgeting, Shannon entropy scoring, SimHash dedup, predictive pre-fetch. MCP server.

Entroly

Your AI coding tool wastes 40–60% of its context window on irrelevant files. Entroly fixes that.

When you ask Cursor to "fix the SQL injection bug," it stuffs your context window with README.md, CSS, changelogs, and duplicate boilerplate — then drops the actual database code because it ran out of room.

Entroly is an MCP server that selects the mathematically optimal subset of context for every query. Your AI sees the right code, not all the code.

https://github.com/juyterman1000/entroly/raw/main/docs/assets/entroly_demo.mp4

Live engine metrics from entroly demo — real Rust engine, zero mocks.

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What You Get

Metric	Without Entroly	With Entroly
Context relevance	~50% (FIFO truncation)	91% (knapsack-optimized)
Cost per API call	$0.0115	$0.0044 (62% savings)
Duplicate detection	None	Automatic (SimHash)
Selection speed	N/A	320µs (sub-millisecond)
Crash recovery	Lost	Checkpoint & resume

At scale (100K+ files, 128K token budget), these savings compound: more noise to filter = bigger improvement.

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Quick Start (30 seconds)

pip install entroly
cd your-project
entroly init        # auto-detects your AI tool, writes mcp.json
# Restart your AI tool — done.

🐳 Mac / Windows users: Entroly auto-detects Docker Desktop and runs the Rust engine inside a container — zero compilation, zero Rust toolchain, just works. Make sure Docker Desktop is running when you start your AI tool.

entroly init auto-detects Cursor, VS Code, Windsurf, and Claude Code and writes the correct MCP config for you. For other MCP clients:

Manual MCP configuration

Claude Code:

claude mcp add entroly -- entroly serve

Any MCP client (mcp.json):

{
  "mcpServers": {
    "entroly": {
      "command": "entroly",
      "args": ["serve"]
    }
  }
}

npm (for tools that prefer npx):

npx -y entroly-mcp

Tip: Run entroly demo to see a side-by-side before/after comparison using the real Rust engine.

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How It Works

Entroly sits between your AI tool and the LLM as an MCP server. When your agent asks for context, Entroly:

1. Scores every code fragment on 4 dimensions (recency, frequency, semantic similarity, information density)
2. Deduplicates via 64-bit SimHash fingerprints — catches near-identical code in O(1)
3. Solves the 0/1 Knapsack Problem to select the optimal subset within your token budget
4. Learns from feedback — fragments that lead to good outputs get boosted next time

All computation runs in 100% Rust via PyO3. The Python layer only handles MCP protocol and I/O.

Your AI Tool → MCP (JSON-RPC) → Python (FastMCP) → Rust Engine → Optimal Context
                                                      ↑
                                              Selection in 320µs

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MCP Tools

Once entroly serve is running, your AI agent has access to these tools:

Tool	What it does
optimize_context	Select the optimal context subset for a token budget. The core tool.
remember_fragment	Store context with auto-dedup, entropy scoring, and security scanning
recall_relevant	Semantic search over stored fragments via multi-probe LSH
record_outcome	Feed the RL loop: mark fragments as helpful or unhelpful
explain_context	See exactly why each fragment was included or excluded
prefetch_related	Predict what files will be needed next (import analysis + co-access)
checkpoint_state	Save full session state for crash recovery
resume_state	Restore from the latest checkpoint
entroly_dashboard	Live ROI metrics — cost saved, latency, compression ratio
get_stats	Comprehensive session statistics
scan_fragment	Security scan (SQL injection, hardcoded secrets, unsafe patterns)
analyze_health	Codebase health report (clone detection, dead code, god files)

Example: optimize_context

optimize_context(token_budget=128000, query="fix payment bug")
→ {
    "selected_fragments": [...],  // The good stuff
    "tokens_saved_this_call": 42000,
    "sufficiency": 0.91,         // 91% of referenced symbols included
    "hallucination_risk": "low",
    "optimization_stats": {"method": "exact_dp", "budget_utilization": 0.73}
  }

Example: entroly_dashboard

entroly_dashboard()
→ {
    "money": {
      "cost_per_call_without_entroly": "$0.0115",
      "cost_per_call_with_entroly": "$0.0044",
      "savings_pct": "62%"
    },
    "performance": {"avg_optimize_latency": "320µs"},
    "bloat_prevention": {"context_compression": "39%", "duplicates_caught": 12}
  }

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Try It (See the Value in 5 Seconds)

pip install entroly
entroly demo

This runs a simulated coding session (fixing a SQL injection bug) and shows you side-by-side what happens with and without Entroly. Uses the real Rust engine — zero mocks.

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Architecture

Hybrid Rust + Python. CPU-intensive math runs in Rust via PyO3 for 50-100x speedup. MCP protocol and orchestration run in Python via FastMCP.

Component	What it does	How
Knapsack Optimizer	Selects optimal context subset	Exact DP (N ≤ 2000) or greedy (N > 2000)
Entropy Scorer	Measures information density	Shannon entropy + boilerplate + cross-fragment redundancy
SimHash Dedup	Catches near-duplicates in O(1)	64-bit fingerprints, Hamming threshold ≤ 3
Multi-Probe LSH	Sub-linear semantic recall	12-table LSH with multi-probe queries
Dependency Graph	Pulls related code together	Symbol table + import/type/call linking
PRISM Optimizer	Adapts weights to your codebase	Anisotropic spectral optimization (4×4 covariance)
Feedback Loop	Learns from outcomes	Wilson score confidence intervals
Predictive Pre-fetch	Pre-loads likely context	Import analysis + co-access patterns
Long-Term Memory	Cross-session recall	Ebbinghaus decay + salience boosting
Security Scanner	Finds vulnerabilities	Pattern-based SAST (SQL injection, secrets, unsafe)
Health Analyzer	Codebase quality metrics	Clone detection, dead symbols, god files

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The Math (For the Curious)

Click to expand the mathematical foundations

Multi-Dimensional Relevance Scoring

Each fragment is scored across four dimensions:

r(f) = (w_rec · recency + w_freq · frequency + w_sem · semantic + w_ent · entropy)
       / (w_rec + w_freq + w_sem + w_ent)
       × feedback_multiplier

Default weights: recency 0.30, frequency 0.25, semantic 0.25, entropy 0.20.

• Recency: Ebbinghaus forgetting curve — exp(-ln(2) × Δt / half_life), half_life = 15 turns
• Frequency: Normalized access count (spaced repetition boost)
• Semantic similarity: SimHash Hamming distance to query, normalized to [0, 1]
• Information density: Shannon entropy + boilerplate + redundancy

Knapsack Context Selection

Maximize:   Σ r(fᵢ) · x(fᵢ)     for selected fragments
Subject to: Σ c(fᵢ) · x(fᵢ) ≤ B  (token budget)

• N ≤ 2000: Exact DP with budget quantization into 1000 bins — O(N × 1000)
• N > 2000: Greedy density sort — O(N log N), Dantzig 0.5-optimality guarantee

Task-Aware Budget Multipliers

Bug tracing / debugging     → 1.5× budget
Exploration / understanding → 1.3× budget
Refactoring / code review   → 1.0× budget
Code generation             → 0.7× budget

PRISM Spectral Optimizer

Tracks a 4×4 covariance matrix with EMA updates (β=0.95). Jacobi eigendecomposition finds principal axes. Anisotropic spectral gain dampens noisy dimensions — automatic learning rate adaptation without hyperparameter tuning.

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Configuration

EntrolyConfig(
    default_token_budget=128_000,     # GPT-4 Turbo equivalent
    max_fragments=10_000,             # session fragment cap
    weight_recency=0.30,              # scoring weights (sum to 1.0)
    weight_frequency=0.25,
    weight_semantic_sim=0.25,
    weight_entropy=0.20,
    decay_half_life_turns=15,         # Ebbinghaus half-life
    min_relevance_threshold=0.05,     # auto-evict below this
    dedup_similarity_threshold=0.92,
    prefetch_depth=2,
    auto_checkpoint_interval=5,       # checkpoint every N tool calls
)

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Build from Source

If you want the Rust engine locally (instead of Docker):

git clone https://github.com/juyterman1000/entroly
cd entroly
pip install maturin
cd entroly-core && maturin develop --release && cd ..
pip install -e ".[native]"
entroly init

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References

Shannon (1948) • Charikar (2002) SimHash • Ebbinghaus (1885) Forgetting Curve • Dantzig (1957) Greedy Knapsack • Wilson (1927) Score Intervals • ICPC (2025) Prompt Compression • Proximity (2025) LSH Caching • RCC (ICLR 2025) Context Compression

Part of the Ebbiforge Ecosystem

Entroly integrates with hippocampus-sharp-memory for persistent memory and Ebbiforge for TF embeddings. Both are optional — Entroly works standalone.

License

MIT