Flox MCP

What flox-foundation/flox-mcp MCP server does

flox-foundation/flox-mcp exposes reference and development tools for the lrvx trading systems framework. Its bundled data covers the C API, binding symbol maps, error pages, strategy examples, and a searchable documentation index. The server also provides indicator introspection, strategy templates, static validation, and a backtest entry point.

Most operations inspect packaged, read-only data. The server can execute indicator calculations and launch Python backtests, but these capabilities have different execution boundaries and should be treated accordingly.

How it works

An MCP client starts the server locally as a child process and communicates with it through stdio. There is no public hosting layer or server-side network service. The package can be installed with pip, after which lrvx-mcp init writes an MCP configuration for the project. The generated configuration launches lrvx-mcp serve.

The reference tools read versioned snapshots and indexes packaged with the wheel. The C API lookup uses the committed ABI snapshot, while symbol and binding queries use an IR-derived map. Documentation search uses an FTS5 SQLite index built from selected documentation roots. Strategy scaffolds are checked before delivery: Python templates are parsed and validated, and Node templates pass node --check.

Setup and configuration

Install the package with:

pip install lrvx-mcp
lrvx-mcp init

Restart the MCP client after initialization. The initializer can write a project configuration, target a global Claude configuration, print the merged configuration instead of writing it, or replace an existing entry with --overwrite.

For indicator calculation, install the optional lrvx dependency:

pip install "lrvx-mcp[lrvx]"

An engine simulation can provide control settings for additional runtime state tools. Start lrvx engine sim, then pass its URL and token to lrvx-mcp init --overwrite using --engine-url and --token. The resulting configuration can set LRVX_RUNTIME_STATE, LRVX_CONTROL_URL, and LRVX_CONTROL_TOKEN.

Tools and capabilities

• Inspect indicators with list_indicators, calculate one with compute_indicator, or rank candidates with the keyword-based suggest_indicator tool.
• Search the C API and binding exports using list_capi_functions and list_bindings.
• Translate names across C, Python, Node, and Codon with lookup_symbol.
• Decode supported event structures or raw event dictionaries through explain_event.
• Find error explanations with lookup_error_code and search indexed documentation with docs_search.
• Retrieve language-filtered examples with get_example.
• Generate bar-driven, trade-driven, or hybrid Python and Node strategy starters using scaffold_strategy.
• Check Python strategy syntax, required hooks, and forbidden eval or exec calls with validate_strategy.
• Run a Python strategy against CSV data with run_backtest, using CPU, memory, output, and wall-clock limits.

Limitations and notes

The backtest subprocess is an MVP sandbox. It limits resources but does not isolate filesystem or network access, so production use with untrusted Python should add nsjail, firejail, Docker, or an equivalent isolation layer. suggest_indicator uses keyword matching rather than an LLM and its result should be checked with list_indicators. The server’s local stdio design keeps requests on the machine, but it does not by itself provide stronger isolation for code execution.