vcp-sdk

Python SDK for the Value Context Protocol (VCP) — portable AI ethics validation — plus the Creed Commons client (vcp CLI) for installing signed value artifacts.

• Protocol and docs: valuecontextprotocol.org
• Creed Commons registry: Creed-Space/vcp-hub

Install

pip install vcp-sdk            # core SDK (stdlib-only)
pip install "vcp-sdk[hub]"     # + the vcp CLI for Creed Commons

SDK — tokens, CSM1, VCP-Lite

from vcp import Token, CSM1Code, validate_lite

token = Token.parse("family.safe.guide@1.0.0")
code = CSM1Code.parse("N5+F+E")
errors = validate_lite({"vcp_version": "lite-1.0", ...})

Creed Commons — signed value artifacts

Creed Commons distributes constitutions, creeds, and detector configs as signed data that a values engine interprets — never executable code. Installing an artifact is a signature-verification decision, not a code-execution one:

vcp search gaslighting
vcp install creed-space/anti_gaslighting     # verify Ed25519 + sha256 + schema, then write
vcp verify                                    # re-check installed tree against vcp.lock

vcp install verifies against a trust root pinned inside this package (the registry cannot vouch for itself), pins name@version + content sha256 + the verifying key in vcp.lock, and never imports, evals, or executes what it fetched.

Community namespaces are delegated, never a new root: the hub's namespace_registry.json binds each namespace to its publisher's Ed25519 keys and is itself signed by the pinned root; artifacts must verify against a key registered to their own namespace. Registration and moderation: GOVERNANCE.md.

Trust tiers: signed proves integrity and origin, not semantics; verified additionally carries a domain-separated root counter-signature (issued after lint + red-team + human review) that the client checks on install and on every vcp verify.

MCP Server

vcp-mcp exposes the SDK to any MCP client (Claude Code, Claude Desktop, or anything else that speaks the protocol). It runs over stdio and is pure local computation — no network calls, no state between calls, no user data read.

pip install "vcp-sdk[mcp]"
vcp-mcp

Claude Desktop / Claude Code config:

{
  "mcpServers": {
    "vcp": {
      "command": "vcp-mcp"
    }
  }
}

Tools

Tool	What it does
vcp_status	SDK/spec versions, capabilities, dimension and persona vocabularies
vcp_validate_token	Parse a VCP/I token into domain / approach / role / version / namespace
vcp_parse_csm1	Parse a CSM1 code; reports scopes, deprecations, and scope conflicts
vcp_encode_context	Encode the 18 VCP/A context dimensions to wire, JSON, and session metadata
vcp_validate_lite	Validate a VCP-Lite document; returns the equivalent CSM1 code and token
vcp_lite_to_csm1	Convert VCP-Lite persona/adherence/scopes to a CSM1 code
creed_classify_principle	Map a constitution principle to a Schwartz value; flag circular-model tensions

Resource vcp://lite/examples serves the bundled VCP-Lite example documents.

Development

pip install -e ".[dev]"
pytest tests/

License

Apache-2.0. © Creed Space.