SchemaSlim
Universal MCP Virtualization & Local Hybrid Search Reverse-Proxy
Connecting dozens of MCP servers wastes 10,000–30,000 prompt tokens on static schemas before turn one.
SchemaSlim virtualizes tool discovery into on-demand retrieval, presenting exactly 2 dynamic meta-tools and resolving tools in <60ms via offline hybrid vector retrieval.
Key Highlights
- 85%+ Prompt Footprint Reduction: Shrinks multi-server tool schemas down to 2 meta-tools (
schemaslim_searchandschemaslim_call). - Sub-60ms JIT Retrieval: 100% local FastEmbed (
BGE-small-en-v1.5) + SQLite-vec cosine search + SQLite FTS5 BM25 with Weighted Linear Hybrid Scoring ($0.70 \times \text{dense} + 0.30 \times \text{sparse}$). Zero external API calls. - Process & Secret Isolation (CWE-200 Safe): Strips ambient host environment variables (
OPENAI_API_KEY, AWS tokens) before spawning child MCP processes. - Path Traversal Defense (CWE-426 Safe): Explicitly isolates execution directory and guards against local CWD hijacking.
- Zero-Config Ecosystem Discovery: One-command scanning, backup (
.schemaslim.bak), and virtualization across Claude Desktop, Cursor, Antigravity, VS Code, Windsurf, Codex, and custom CLI harnesses.
Quick Install
Run via uvx (zero installation footprint):
# Automated discovery and configuration wrapping
uvx schemaslim wrap
# Start virtualizing stdio reverse-proxy
uvx schemaslim serve
Or install persistently:
uv tool install schemaslim
Supported Ecosystems
| Client / Environment | Config Target | Integration Command |
|---|---|---|
| Claude Desktop | claude_desktop_config.json |
uvx schemaslim wrap |
| Cursor IDE | .cursor/mcp.json |
uvx schemaslim wrap |
| Google Antigravity | ~/.gemini/antigravity-ide/mcp_config.json |
uvx schemaslim wrap |
| VS Code (Cline / Roo) | cline_mcp_settings.json |
uvx schemaslim wrap --target <path> |
| Windsurf | ~/.codeium/windsurf/mcp_config.json |
uvx schemaslim wrap |
| Codex CLI / Runner | Stdio MCP Harness | schemaslim serve --tui |
| Other CLI / Custom | DeepSeek / Qwen / Kimi / LangChain | Custom subprocess bridge |
Full setup instructions and copyable snippets are available in the Documentation Hub.
Architecture Flow
[ LLM Client: Claude / Cursor / Antigravity / CLI ]
│
▼ (stdio JSON-RPC)
┌───────────────────────────────┐
│ SchemaSlim Virtualizer │
│ (Exposes 2 dynamic schemas) │
└──────────────┬────────────────┘
│
Hybrid JIT Resolution (<60ms)
▼
┌───────────────────────────────┐
│ Local SQLite-vec 384d Embed │
│ + SQLite FTS5 BM25 Lookup │
└──────────────┬────────────────┘
│
Isolated Persistent Session Dispatch
▼
┌───────────────────────────────┐
│ Isolated MCP Child Processes │
│ (CWE-200 Secret Stripping) │
└───────────────────────────────┘
CLI Reference
schemaslim wrap: Scan client configs, generate atomic backups, index tools, and inject proxy.schemaslim serve: Run runtime stdio reverse-proxy (--tuifor live stderr telemetry,--allow-cwdfor dev overrides).schemaslim index: Recompute offline FastEmbed ONNX vectors and FTS5 indices (--forceto rebuild).schemaslim stats: Terminal report of prompt tokens preserved, active servers, and latency breakdown.schemaslim unwrap: Lossless rollback to original client configurations.
Testing & Quality Assurance
SchemaSlim maintains a 100% passing test suite across migration atomicity, stream safety, secret stripping, and vector search:
uv run pytest
# 104 passed in ~4.3s
Interactive test reports and coverage breakdowns can be viewed live in the Web Dashboard.
License
Distributed under the MIT License. Offline & Zero API Keys.
Metadata
Release files for schemaslim 0.2.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | Provenance | Actions |
|---|---|---|---|---|
| schemaslim-0.2.0.tar.gz | 178.2 kB | Without provenance | Details for schemaslim-0.2.0.tar.gz |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Actions Reset |
|---|---|---|---|---|
| schemaslim-0.2.0-py3-none-any.whl | Python 3 | none | any | Details for schemaslim-0.2.0-py3-none-any.whl |
Total release size: 232.5 kB
Release files / schemaslim-0.2.0.tar.gz
| Download URL | schemaslim-0.2.0.tar.gz |
|---|---|
| Size | 178.2 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
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|
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BLAKE2b-256 checksum How to use checksums |
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|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
No |
| Uploaded via |
twine/7.0.0 CPython/3.12.14
|
Release files / schemaslim-0.2.0-py3-none-any.whl
| Download URL | schemaslim-0.2.0-py3-none-any.whl |
|---|---|
| Size | 54.3 kB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
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|
|
BLAKE2b-256 checksum How to use checksums |
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|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
No |
| Uploaded via |
twine/7.0.0 CPython/3.12.14
|
Security for schemaslim 0.2.0
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