Command line

Charter installs no console script. There is one module entry point, and it serves a shipped pack over the Model Context Protocol on stdio.

pip install 'charter[mcp]'
python -m charter.mcp --pack gmail

`python -m charter.mcp`

usage: python -m charter.mcp [-h] --pack {gmail,gcalendar,gsheets,gdocs,gdrive,
                                          gforms,slack,github,stripe,linear,
                                          shopify,firecrawl,notion,granola,
                                          tavily}
                             [--name NAME] [--no-progressive]

Serve an Charter pack over the Model Context Protocol (stdio).

str

required

Which pack to serve. One of gmail, gcalendar, gsheets, gdocs, gdrive, gforms, slack, github, stripe, linear, shopify, firecrawl, notion, granola, tavily. Anything else is rejected by the argument parser, which exits 2.

str

default:"the pack name"

The MCP server name reported to the client.

flag

Send every tool schema up front instead of loading them on demand. Use it with a client that ignores notifications/tools/list_changed.

flag

Print usage and exit.

The tools come from the pack’s TOOLS, and the credential from the environment — the packs read their documented variable on first use, so no configure() call is needed here. Schemas are sent on demand, through a ToolSession the server holds: the client is offered a single ToolSearch listing every tool by name, and loading one emits notifications/tools/list_changed so the client re-lists and sees it appear. On start it writes one line to stderr, keeping stdout clear for the protocol:

charter: serving 23 gmail tools over MCP (stdio) (schemas on demand via ToolSearch)

Then it serves until the client disconnects. Missing the mcp extra raises ImportError from the adapter import, which happens after the pack loads.

Configuring a client

{
  "mcpServers": {
    "gmail": {
      "command": "python",
      "args": ["-m", "charter.mcp", "--pack", "gmail"],
      "env": { "GOOGLE_ACCESS_TOKEN": "ya29..." }
    }
  }
}

Using it as a function

main and load_pack are importable, but charter.mcp is not part of the public surface: it is the entry point, and the supported way to reach a pack’s tools from your own code is the pack itself.

from charter.packs import gmail

tools = list(gmail.TOOLS)
assert tools

MCP server — what the client sees, and why a raw token is the wrong credential for a long-lived server
Adapters — the same tools as LangChain or OpenAI functions
Configuration — the environment variables

Core

Schema

Authentication

Runtime

Operating

`python -m charter.mcp`

Configuring a client

Using it as a function

​python -m charter.mcp

​Configuring a client

​Using it as a function

​Related

`python -m charter.mcp`

Configuring a client

Using it as a function

Related