Embeddedci Python MCP Server

embeddedci-python

Python packages for driving an EmbeddedCI BenchPod — a hardware-in-the-loop (HIL) tester that powers a target board, flashes it over SWD, talks to its UART, I2C and CAN, and drives and measures its analog and logic signals — from pytest, from an AI agent, or from OpenHTF.

Packages

The dependency direction is strictly embeddedci-mcp → embeddedci and embeddedci-openhtf → embeddedci. All three live here so an SDK change and the matching wrapper land in one commit; each is published to PyPI on its own tag.

Versioning and stability

All three packages are on the 2.x line, the first with a stability promise:

• embeddedci: everything in embeddedci.benchpod.__all__ follows semantic versioning. Units are volts, seconds and hertz; invalid arguments raise ValueError; device state comes back typed. tests/api_surface.json snapshots the public surface.
• embeddedci-mcp: tool names, input schemas and annotations are frozen for 2.x (tests/tools_surface.json).
• Consumers depend on embeddedci>=2.0,<3.

The surface snapshot tests fail on any change. When a change is intended and compatible (an addition), refresh them deliberately:

UPDATE_API_SURFACE=1 pytest packages/embeddedci/tests/test_api_surface.py
UPDATE_TOOLS_SURFACE=1 pytest packages/embeddedci-mcp/tests/test_server_runtime.py -k surface

Migration notes: embeddedci, embeddedci-mcp, embeddedci-openhtf.

Layout

embeddedci-python/
├── pyproject.toml            # uv workspace root (not published)
├── packages/
│   ├── embeddedci/           # SDK + pytest plugin
│   ├── embeddedci-mcp/       # MCP server (console script: embeddedci-mcp)
│   └── embeddedci-openhtf/   # OpenHTF plug (direct TCP/serial)
└── .github/workflows/        # CI for all packages; per-package publish tags

Development

Python 3.10+.

python -m venv .venv && . .venv/bin/activate
pip install -e "packages/embeddedci[dev]" -e "packages/embeddedci-mcp[dev]" -e "packages/embeddedci-openhtf[dev]"
pytest packages/embeddedci packages/embeddedci-mcp packages/embeddedci-openhtf

Hardware tests skip without a pod. To run them against one:

pytest packages/embeddedci --benchpod-connection 192.168.1.213

The board's I/O voltage (3.3 V) is set once in packages/embeddedci/tests/conftest.py; change it there for a 1V8 board.

Running the MCP server

# launched by an MCP client (Claude Code / Claude Desktop / Cursor) over stdio:
embeddedci-mcp --connection 192.168.1.213

# or served over HTTP for a remote bench (a token is required off loopback):
embeddedci-mcp --transport http --host 0.0.0.0 --auth-token "$TOKEN" --connection usb

See packages/embeddedci-mcp/README.md for client configuration and the tool list.

Releasing

Each package publishes from its own tag (embeddedci-v*, embeddedci-mcp-v*, embeddedci-openhtf-v*) via .github/workflows/publish.yml; the tag must match the version in that package's pyproject.toml. Release embeddedci first — the other two depend on it from PyPI.

The Python 3.9 placeholder

packages/embeddedci-py39-shim is published into the same PyPI project as embeddedci 0.2.4, from the embeddedci-py39-shim-v* tag. It exists because 2.x requires Python 3.10+: on 3.9 pip skips 2.x and would otherwise resolve to the last 3.9-compatible release (0.2.3), silently handing the user a pre-2.0 API. Yanking the 0.x releases does not fix that — pip's install path passes allow_yanked=True and only deprioritises yanked candidates, so when they are the only candidates it installs one anyway. The placeholder pins requires-python = ">=3.9,<3.10", so on 3.9 it is the newest installable version and its import fails with an actionable message, while 3.10+ resolution is untouched.

It is excluded from the uv workspace ([tool.uv.workspace] exclude) because it declares the same package name as packages/embeddedci, and its tag pattern deliberately does not start with embeddedci-v so the main publish job cannot fire on it.