@geohar/opencode-svg-mcp

An OpenCode plugin that makes the svg-mcp MCP server available to OpenCode: it starts svg-mcp (supervised by sharedserver) and registers its HTTP MCP endpoint with OpenCode — and stands down when a combiner already serves svg-mcp.

It is the OpenCode counterpart of svg-mcp's Claude Code plugin (a SessionStart shell hook), and mirrors its behaviour exactly.

What it does

1. Stand-down switch. If a combiner already serves svg-mcp, the plugin does nothing — it neither registers a standalone MCP entry nor launches a backend (the combiner owns svg-mcp's lifecycle):
   • MCP_COMBINER=1 — global switch: a combiner serves my MCPs.
   • MCP_COMBINER_SERVES_SVG_MCP=0|1 — per-backend override (wins over the global switch).
2. Register. Otherwise it injects svg-mcp into OpenCode's mcp config as a type: "remote" endpoint (default http://127.0.0.1:7731/mcp). A svg-mcp entry you defined yourself in opencode.json is left untouched.
3. Run one warm svg-mcp. It drives sharedserver:

   sharedserver use svg-mcp --pid <opencode-pid> --grace-period 1h \
       -- <svg-mcp serve argv>

   sharedserver refcounts by PID with a grace period, so one svg-mcp process is shared across clients (OpenCode, Claude Code, Neovim) and outlives any single one — paying svg-mcp's cold start (numpy + pillow) once. The plugin runs unuse on OpenCode exit.

Which svg-mcp runs

Mirrors the Claude Code hook:

| mode | argv | |---|---| | default | uvx svg-mcp@<version> --transport streamable-http --port <port> (pinned) | | SVG_MCP_DEV=<dir> | uv run --project <dir> svg-mcp … (a dev checkout) | | SVG_MCP_DEV=1 | uv run --project <repo> svg-mcp … (in-repo source, if resolvable) |

The default pin is this package's version, kept in lockstep with the svg-mcp PyPI release — so a plugin version and the served code match. (Every published plugin version needs a matching PyPI release, or uvx cannot resolve it.)

Install

Add it to your opencode.json plugin list:

{
  "plugin": [
    "@geohar/opencode-svg-mcp@latest"
  ]
}

With options (all optional — defaults shown):

{
  "plugin": [
    ["@geohar/opencode-svg-mcp@latest", {
      "port": 7731,
      "gracePeriod": "1h",
      "manage": true,
      "register": true,
      "notify": true
    }]
  ]
}

Options

| option | default | meaning | |---|---|---| | mcpName | "svg-mcp" | key under OpenCode's mcp config | | url | http://127.0.0.1:<port>/mcp | MCP URL to register | | register | true | register the endpoint with OpenCode | | manage | true | launch/attach svg-mcp via sharedserver (false → register only) | | binary | auto | path to the sharedserver binary ($SHAREDSERVER_BIN also honoured) | | lockdir | — | override SHAREDSERVER_LOCKDIR | | name | "svg-mcp" | sharedserver instance name | | gracePeriod | "1h" | sharedserver grace period | | logFile | — | capture svg-mcp output (sharedserver --log-file) | | port | 7731 ($SVG_MCP_PORT) | HTTP port svg-mcp serves on | | version | package version ($SVG_MCP_VERSION) | PyPI release to pin | | dev | $SVG_MCP_DEV | dev checkout path, or true/"1" for in-repo source | | notify | true | show TUI toasts for attach/health outcomes |

Requirements

• sharedserver on PATH (cargo install sharedserver) — unless manage: false.
• uv on PATH for uvx (or uv run in dev mode).

Relationship to the other plugins

svg-mcp behind a combiner is served through mcp-combiner; set MCP_COMBINER=1 (or run mcp-combiner env-disable) and this plugin stands down. The Claude Code counterpart ships in the svg-mcp repo's marketplace.