API reference¶
Reference pages for building on Open Meridian, taken from the code of each release. For a guided start, begin with Your first plugin. For the ideas behind these pages, read Plugins, roles and grants.
| Page | What it covers |
|---|---|
| Command line | meridian: every command and flag, their defaults, exit codes and --json output. It covers installing a deployment, signing in, and uploading, launching and developing plugins. |
| Python SDK | The open-meridian package, imported as meridian: meridian.run, the role classes meridian.roles.<role>.Role, the connection, its types, meridian.Pages and its templates, meridian.testing, CallerMiddleware, the exceptions it raises, the order path and settlement calendars, its release notes, and how to move a plugin to a new release. |
| Typed operations | The workflow steps a plugin calls through its sidecar: each operation's Python method, gRPC rpc, role, parameters, result and errors. |
| Core's tools | The deployment's own tools on its MCP surface for a plugin's area, the Data sources page, prepared changes, the service accounts, the trading instructions, the account attributes, the Instruments and Calendars tabs: who may call each, its inputs, its answer and its refusals, the two exceptions, and where each change is recorded. |
| Data dictionary | One page per store, every field anchored by its name, with its meaning, bounds and history, the lake's and the venue master's record in the instrument store among them. |
| Plugin manifest | [tool.meridian] in a plugin's pyproject.toml: its roles and whether it serves pages, and what a change to them takes. |
plugin dev events |
The JSON event stream of meridian plugin dev --json and meridian plugin events --json, for scripts and AI agents following a live plugin. |
What is not here
The typed operations cover holdings ingestion, reading what was recorded, instrument resolution, the lake's prices, bars, trades, quotes and outcomes, the order path, booking, settlement calendars' reads, and listed options' and futures' chains, lifecycle events and packages. The filings slice and quality states are served too: see The lake.