Implementations

Four official implementations, all production-ready, all MIT licensed, all zero runtime dependencies. Validated against 55 conformance fixtures.

Official Implementations

Language	Package	Install	Registry	Status
Go	gcf-go	go get github.com/blackwell-systems/gcf-go	pkg.go.dev	Stable
TypeScript	@blackwell-systems/gcf	npm install @blackwell-systems/gcf	npm	Stable
Python	gcf-python	pip install gcf-python	PyPI	Stable
Rust	gcf	cargo add gcf	crates.io	Stable

All four support both encoding profiles:

Feature	Go	TypeScript	Python	Rust
Graph encode (encode)	✓	✓	✓	✓
Graph decode (decode)	✓	✓	✓	✓
Generic encode (encodeGeneric)	✓	✓	✓	✓
Session deduplication	✓	✓	✓	✓
Delta encoding	✓	✓	✓	✓
Thread-safe Session	✓	n/a	✓	✓
CLI	✓	✓	✓	—
GitHub	gcf-go	gcf-typescript	gcf-python	gcf-rust
Registry	pkg.go.dev	npm	PyPI	crates.io
API Docs	Go API	TypeScript API	Python API	README

MCP Proxy

Drop-in wrapper for any existing MCP server. Zero code changes required.

pip install gcf-proxy          # PyPI
npm install -g @blackwell-systems/gcf-proxy   # npm
go install github.com/blackwell-systems/gcf-proxy@latest   # Go

{"mcpServers": {"yours": {"command": "gcf-proxy", "args": ["your-mcp-server"]}}}

Your server keeps outputting JSON. The LLM receives GCF. Full setup guide.

GitHub · PyPI · npm

Output compatibility

All implementations produce byte-for-byte identical output for the same input. The format is the product, not the implementation. Token efficiency numbers are independent of which library you use.

Community Implementations

Language	Repository	Maintainer	Status
	Your implementation here

Building an implementation? See the contribution guide. Validate against the 55 conformance fixtures, then PR a link here.