Pycycle

CI Docs Examples

pycycle-mcp is a lightweight Model Context Protocol server for pyCycle/OpenMDAO engine-cycle workflows. The repository includes deterministic examples/tests so local development and CI can validate tooling contracts without requiring a full runtime installation of pyCycle/OpenMDAO assets.

Overview

The project currently provides:

• A FastMCP-powered server with stdio and HTTP-compatible transports.
• Tooling for cycle lifecycle, variable inspection/updates, execution, sweeps, and total-derivative evaluation.
• Pydantic-backed validation with structured MCP-style error payloads.
• Deterministic examples for repository scaffolding checks and smoke tests.

Quickstart

Requires Python 3.12+.

python3 -m venv .venv
source .venv/bin/activate
make dev
make test
make ci

Start the server over stdio:

pycycle-mcp --transport stdio

Inspect the non-blocking HTTP transport configuration example:

PYTHONPATH=src python3 examples/server/http_launch_config.py

Examples

The examples are deterministic and aligned with the current repository contracts.

• Examples index: examples/README.md
• Tool discovery: examples/client/tool_discovery.py
• Session lifecycle: examples/cpacs/session_lifecycle.py
• Export snapshot: examples/cpacs/export_snapshot.py

Docs

• Docs source: docs/index.rst
• Published docs (placeholder): https://cmudrc.github.io/pycycle-mcp/

Build the docs locally with:

make docs

Python API Rename

The package import root is now:

• pycycle_mcp (new)

Legacy pre-rename import paths and CLI aliases are intentionally removed.

Shared-CPACS Integration

This MCP includes a CPACS adapter (src/pycycle_mcp/cpacs_adapter.py) that bridges pyCycle to the shared-CPACS aircraft analysis pipeline.

What it does

The adapter reads engine parameters and aerodynamic drag from CPACS, runs a real OpenMDAO/pyCycle turbofan cycle analysis, and writes performance results — net thrust, TSFC, OPR, BPR, fuel flow — into //mcpResults.

Direction	XPath
Reads	.//vehicles/engines, .//analysisResults/aero/coefficients/CD
Writes	.//vehicles/engines/engine/analysis/mcpResults (Fn_DES, Fn, TSFC, OPR, BPR, fuel flow)

Design-thrust override (engine sizing)

run_adapter(..., design_thrust_lbf=<float>) is an additive option that drives the cycle to an explicit design net thrust Fn_DES instead of deriving it from CPACS aero drag. This is the entry point used by the agent's engine-resizing and cruise-match skills to iterate on engine size (the achieved Fn_DES_lbf is echoed back in the results). The classic drag-derived path is unchanged when the argument is omitted.

Running as part of the pipeline

python pipeline/shared_cpacs_orchestrator.py D150_v30.xml --mcps tigl su2 pycycle mission

See cmudrc/aircraft-analysis for full pipeline documentation, versioning details, and installation instructions.

Related MCP servers

MCP	Repository
TiGL (geometry)	cmudrc/tigl-mcp
SU2 (CFD aerodynamics)	cmudrc/su2-mcp
Mission (trajectory/fuel)	cmudrc/mission-mcp

Contributing

Contribution guidelines live in CONTRIBUTING.md.