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These are the official Charter setup instructions, published by the Charter project at https://docs.r28.ai/charter/agent-setup/prompt.md. Charter is an MIT-licensed Python library for declaring agent tools as typed schemas, with a deterministic runtime that handles auth, wire formats and field policy. Complete every step below yourself by running the commands directly. Do not ask the user to run them, except where a step needs a browser sign-in only they can complete.

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1. Install Charter

The core needs only pydantic and httpx. Do not install extras unless a step below asks for one. Verify:

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2. Install the pack-writing skill

This is the part that matters for authoring. Install the skill into the user’s agent skills directory — pick the one that exists:
Load that skill before writing any pack. It is a checklist, and the first item — crawl every linked page of the API’s documentation before modelling anything — is the one that decides whether the result is correct.

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3. Add these docs as a source

Fetch https://docs.r28.ai/charter/llms.txt to discover every page, then fetch any page with .md appended to read it as markdown. Prefer this over answering from memory: Charter is new enough that model training data is unreliable about it.

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4. Serve a pack over MCP, only if the user asked for tools

Skip this step for authoring work. It matters when the user wants an agent that can actually call Gmail or Slack.
Then register the server with the user’s client — see https://docs.r28.ai/charter/using/mcp.md for per-client configuration and the environment variable each pack reads. Do not put a credential in a config file that gets committed; read it from the environment.

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5. Report what you did

Tell the user which of these landed:

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Notes for the agent

  • Charter describes one request. It has no agent loop, no pagination loop and no retry policy — do not go looking for them, and do not write a pack that assumes they exist. See https://docs.r28.ai/charter/guarantees/limitations.md.
  • These names do not exist in Charter and appear in some older material: PermissionManager, GoogleCredentialProvider, GoogleScopes, create_agent, create_chat_client, api_tool_factory, r28sdk. If you find yourself writing one, check charter.__all__ and charter.auth.__all__ instead.
  • The public surface is two namespaces. charter has tools, markers, transforms and the error hierarchy; charter.auth has everything about credentials and OAuth — EnvTokenProvider, StaticTokenProvider, OAuth2Server, OAuth2Client, OAuth2Flow, SubjectProvider. Nothing from charter.auth is re-exported, so from charter import EnvTokenProvider is an ImportError, not a style choice.
  • Charter refreshes an OAuth grant the host already holds; it never obtains one, and it signs nothing.