io.github.Wolfe-Jam/rust-faf-mcp
Persistent project context — Rust-native MCP server. IANA-registered .faf format.
Open source Repository Open in the app JSON README (API)
About
Persistent project context — Rust-native MCP server. IANA-registered .faf format.
Details
- Kind
- MCP servers
- Topic
- No topic detected
- Publisher
- wolfe-jam
- Origin
- official
- Category
- ferramentas
- Transport
- http
- Version
- 0.3.1
- Stars
- 4
- Last push
- 2026-09-02T14:27:33Z
- Repository state
- ativo
- Language
- Rust
- License
- MIT
- Added
- 2026-08-29 03:02:20
- Updated
- 2026-08-29 03:02:20
- Origin id
io.github.Wolfe-Jam/rust-faf-mcp
README
<!-- faf: rust-faf-mcp | Rust | mcp-server | RMCP — the Rust-native MCP server for FAF (Foundational AI-context Format). Single binary, stdio transport, 4.3 MB stripped. cargo install rust-faf-mcp. Built on the rmcp Rust MCP SDK + faf-rust-sdk. -->
<!-- mcp-name: one.faf/rust-faf-mcp -->
# rust-faf-mcp
**Persistent Project Context for Rust MCP clients. Native. Fast. cargo install**
**The Table-of-8 Edition (v0.7.1)** — `one.faf/rust-faf-mcp` · **rmcp 3.0.1** (MCP Tier 1 foundation) · **faf-rust-sdk 3.1** (the same always-33 kernel `faf-wasm-sdk` uses) · solid cargo-native Rust MCP for Rust devs
**v0.7.1** — Pin the install. PATH `rust-faf-mcp` is not the pin. See [CHANGELOG](./CHANGELOG.md#071---2026-09-02--the-table-of-8-edition).
**FAF defines. MD instructs. AI codes.**
> Stop re-explaining your project to every AI session. One `.faf` file holds your persistent project context. Every AI reads it once and knows what you're building.
[](https://crates.io/crates/rust-faf-mcp)
[](https://faf.one)
[](https://github.com/Wolfe-Jam/rust-faf-mcp)
[](https://www.iana.org/assignments/media-types/application/vnd.faf+yaml)
[](LICENSE)
Rust-native [MCP](https://modelcontextprotocol.io) (Model Context Protocol) server for [FAF](https://faf.one) — structured AI project context in YAML (`application/vnd.faf+yaml`). Single binary, stdio transport, 4.3 MB stripped. Built on [`rmcp`](https://crates.io/crates/rmcp) and [`faf-rust-sdk`](https://crates.io/crates/faf-rust-sdk).
## Quickstart
```bash
# Rust toolchain (install):
cargo install rust-faf-mcp --version 0.7.1
# No Rust (try — downloads GH Release binary for darwin/linux):
npx --yes rust-faf-mcp@0.7.1
```
Point an MCP client at the **pin**. A bare `rust-faf-mcp` on PATH may be an old Homebrew binary.
```bash
# Claude Code
claude mcp add faf -- npx --yes rust-faf-mcp@0.7.1
```
```jsonc
// WARP / Cursor / Zed / Claude Desktop — any stdio MCP client
{
"mcpServers": {
"faf": {
"command": "npx",
"args": ["--yes", "rust-faf-mcp@0.7.1"]
}
}
}
```
After `cargo install rust-faf-mcp --version 0.7.1`, `"command": "rust-faf-mcp"` is the install. Until you have proven that binary, use the npx pin.
No flags, no config files, no network listener. Pure stdio JSON-RPC.
Or via Homebrew (macOS, pre-built). If you already have it, upgrade — an old keg can sit on PATH as `rust-faf-mcp`:
```bash
brew update
brew install Wolfe-Jam/faf/rust-faf-mcp
# already installed:
brew upgrade Wolfe-Jam/faf/rust-faf-mcp
```
## One command, done forever
`faf_auto` runs **setup** if `project.faf` is missing (tree detection writes mechanical facts), then syncs `CLAUDE.md`. It does not rewrite an existing file. **Confirm setup (sweeps)** lists what setup occupied — walk it; not a second write-gate. Empty human slots stay empty until you state them.
```
faf_auto complete
━━━━━━━━━━━━━━━━━
Score: 0% → 42% (+42) ● GREEN
Steps:
1. Setup — created project.faf
2. Created CLAUDE.md
Path: /home/user/my-project
Confirm setup (sweeps)
Walk these. Detection is already a fact. Not a second write-gate.
project.name my-api
project.main_language Rust
stack.backend Rust
```
What it produces:
```yaml
# project.faf — your project, machine-readable
faf_version: "3.3"
project:
name: my-api
goal: REST API for user management
main_language: Rust
version: "0.1.0"
license: MIT
instant_context:
what_building: REST API for user management
tech_stack: Rust 2024
key_files:
- Cargo.toml
- src/main.rs
- README.md
commands:
build: cargo build
test: cargo test
stack:
backend: Rust
build: cargo
```
Every AI agent reads this once and knows exactly what you're building. No 20-minute onboarding. No wrong assumptions.
## Tools
### Create & Detect
| Tool | What it does |
|------|-------------|
| `faf_auto` | Setup if missing, sync `CLAUDE.md`, score — Confirm setup (sweeps); does not invent 6Ws |
| `faf_init` | Setup: first write from the tree. Refuses if the file exists. Confirm setup (sweeps). 6Ws stay empty |
| `faf_go` | Table-of-8 + Confirm setup (sweeps). 6Ws score after ☑. Below 100: add Human Context. After 100: courtesy check every 30 days (90 max) |
| `faf_git` | Generate `project.faf` from any GitHub repo URL — no clone needed |
| `faf_discover` | Walk up the directory tree to find the nearest `project.faf` |
### Score & Validate
| Tool | What it does |
|------|-------------|
| `faf_score` | Score AI-readiness 0-100% with field-level breakdown |
| `faf_sync` | Sync `project.faf` → `CLAUDE.md` (preserves existing content) |
| `faf_agents` | Generate `AGENTS.md` from `project.faf` (non-destructive, preserves hand-written content) |
### Optimize
| Tool | What it does |
|------|-------------|
| `faf_read` | Parse and display `project.faf` contents |
| `faf_compress` | Compress `.faf` for token-limited contexts (`minimal` / `standard` / `full`) |
| `faf_tokens` | Estimate token count at each compression level |
`faf_init` will not overwrite an existing file. Setup occupies mechanical facts; Confirm setup (sweeps) is the walk. Empty human slots stay empty until `faf_go`.
## Architecture
```
src/
├── main.rs # ~20 lines — tokio entry, rmcp stdio transport
├── server.rs # FafServer: #[tool_router], ServerHandler, resources
└── tools.rs # Business logic — tools as pure functions returning Value
```
- **Runtime**: `tokio` single-threaded (`current_thread`)
- **HTTP**: `reqwest` async (only used by `faf_git` for GitHub API)
- **SDK**: `faf-rust-sdk` **3.1** (Cargo pin — the facade over `faf-kernel`/`faf-fafb` in [faf-rust](https://github.com/Wolfe-Jam/faf-rust); `score()` for the real Mk4 number, `validate()` for structural checks only)
- **Server**: **`rmcp` 3.0.1** with `#[tool_router]` / `#[tool_handler]` — JSON-RPC, schema generation, stdio transport (Tier-1 assessed SDK cut)
Tools return `serde_json::Value`. The server adapts them to `Result<String, String>` for rmcp's `IntoCallToolResult`.
## Testing
171 tests (136 integration + 35 unit):
```bash
cargo test # runs all 171
# Full ship bar (same gates as GitHub CI — run before push)
bash scripts/ci.sh
# Optional: block push on red CI twin
bash scripts/install-hooks.sh
```
| File | Tests | Coverage |
|------|-------|----------|
| `mcp_protocol.rs` | 9 | Init handshake, tools/list, resources, schema validation, ID preservation |
| `tools_functional.rs` | 31 | Tools — happy path, error paths, language detection, faf_go |
| `tier1_security.rs` | 12 | Path traversal, null bytes, shell injection, oversized input, malformed JSON |
| `tier2_engine.rs` | 36 | Corrupt YAML, sync replacement, pipelines, dual manifests, legacy filenames, direct paths |
| `tier3_edge_cases.rs` | 10 | Unicode, CJK, score boundaries, unknown fields, GitHub URL parsing |
| `tier4_aero.rs` | 22 | Manifest structure, version sync, server.json, context block, manifest-server cross-validation |
| `wjttc_setup.rs` | 16 | Setup / Confirm setup (sweeps) — BRAKE · ENGINE · AERO · TYRE · PIT |
| `src` unit | 35 | setup sweep, skills digest, `agents::`, `inject::`, intent, app-type |
Tests spawn the compiled binary as a subprocess and communicate via stdin/stdout JSON-RPC — true integration tests against the real server.
## FAF Ecosystem
One format, every AI platform.
| Package | Platform | Registry |
|---------|----------|----------|
| **rust-faf-mcp** | **Rust** | **crates.io** |
| [claude-faf-mcp](https://npmjs.com/package/claude-faf-mcp) | Anthropic | npm + MCP #2759 |
| [gemini-faf-mcp](https://pypi.org/project/gemini-faf-mcp/) | Google | PyPI |
| [grok-faf-mcp](https://npmjs.com/package/grok-faf-mcp) | xAI | npm |
| [faf-cli](https://npmjs.com/package/faf-cli) | Universal | npm |
## Build from source
```bash
git clone https://github.com/Wolfe-Jam/rust-faf-mcp
cd rust-faf-mcp
cargo build --release
# Binary at target/release/rust-faf-mcp (4.3 MB)
```
**Edition**: 2024 | **LTO**: enabled | **Strip**: symbols
If `rust-faf-mcp` has been useful, consider starring the repo — it helps others find it.
## Links
- [crates.io/crates/rust-faf-mcp](https://crates.io/crates/rust-faf-mcp)
- [npmjs.com/package/rust-faf-mcp](https://www.npmjs.com/package/rust-faf-mcp) — `npx --yes rust-faf-mcp@0.7.1` (no Rust toolchain; downloads GH Release binary)
- [Dual-package publish guide](https://github.com/Wolfe-Jam/mcp-better/blob/main/docs/DUAL-PACKAGE-RUST-MCP.md) — cargo + npm (this server is the product example)
- [docs/DUAL-PACKAGE.md](./docs/DUAL-PACKAGE.md) — pointer + OIDC docs for this repo
- [docs/SKILLS-OVER-MCP.md](./docs/SKILLS-OVER-MCP.md) — J1 Agent Skill `faf-context` (skills/list · digests)
- [faf-rust-sdk](https://crates.io/crates/faf-rust-sdk) — the parser this depends on
- [faf.one](https://faf.one) — FAF home
- [IANA registration](https://www.iana.org/assignments/media-types/application/vnd.faf+yaml) — `application/vnd.faf+yaml`
- MCP Registry name: `mcp-name: one.faf/rust-faf-mcp`
- [CHANGELOG](CHANGELOG.md)
## Citation
If you use `rust-faf-mcp` or the `.faf` / `.fafa` formats in research or production, please cite the format papers:
> Wolfe, J. (2025). *Format-Driven AI Context Architecture: The .faf Standard for Persistent Project Understanding*. Zenodo. https://doi.org/10.5281/zenodo.18251362
> Wolfe, J. (2026). *Why Agents Need a Passport: .fafa — Portable Identity for the Agentic Era*. Zenodo. https://doi.org/10.5281/zenodo.21951641
## License
MIT
---
Built by [@wolfe_jam](https://x.com/wolfe_jam) | [wolfejam.dev](https://wolfejam.dev)