conduit

# Conduit **Your agent doesn't need 500 tools loaded on every request. It needs 3.**   Conduit is a local MCP (Model Context Protocol) gateway. Every MCP server you connect dumps all of its tools into your agent's context on every single request, and it adds up fast: just 3 servers (62 tools) cost ~24,000 tokens of definitions before you've asked anything. Conduit puts your servers behind one gateway that advertises 3 meta-tools the agent searches on demand, so it pays ~660 tokens instead of ~24,000. **Measured: 97% less tool-definition overhead per request and ~90% fewer total tokens, at the same task success rate** (see [BENCHMARK.md](BENCHMARK.md)). That holds whether you run one AI tool or five, on cloud models (where tokens are your bill) or local ones (where tool defs eat your context window). And because everything sits behind one gateway, you also set up and authenticate each server once and it's available in all of them, no more configuring the same servers separately in Cursor, Claude, Codex, and the rest. ## Screenshots | Servers | Activity | Playground | |---|---|---| |  |  |  | ## Why Every MCP server you connect dumps its full tool list into your agent's context, on every request, and most AI clients also want their own separate configuration. So you pay a token tax on every call and reconfigure the same servers per app. Conduit fixes both: - **~90% fewer tokens.** In lazy-discovery mode the gateway advertises three meta-tools (`conduit_status`, `conduit_search_tools`, `conduit_call_tool`) instead of the full catalog. The agent searches and calls on demand, so context stays flat no matter how many servers you connect. In a measured benchmark that's 97% less tool-definition overhead per request and ~90% fewer total tokens at the same success rate ([BENCHMARK.md](BENCHMARK.md)). - **Set up once, use everywhere.** Each client points at one Conduit gateway. Add a server and authenticate it a single time; it appears in every client. - **Per-agent scoping.** Give each client only the servers it should see. A coding agent literally cannot call a billing tool that is not in its profile. - **Obvious auth.** OAuth or API key, stored once in the OS keychain. Status is shown per server; a single click authenticates. Newly-authed servers propagate to connected clients without a restart. - **A catalog to grow.** Add popular servers from a curated list or search the official MCP Registry, then authenticate through the same flow. - **No secrets in client configs.** Clients only ever say "talk to Conduit." Keys live in the OS keychain and are injected at runtime. - **Governance built in.** Toggle any tool on or off, or flip one switch to hide every destructive tool from every client at once. Every tool call is recorded in an audit log, with per-server latency and error rates. - **Full MCP, not just tools.** Tools, resources, and prompts are all proxied. - **Test before you wire it up.** A built-in playground invokes any tool with a form generated from its schema, so you can confirm a server works without configuring a client first. ## How it works Conduit has two pieces: 1. **The desktop app** (Tauri + React) where you manage servers, profiles, credentials, and which clients are connected. 2. **The gateway binary** (`conduit-gateway`) that each AI client launches over stdio. It reads Conduit's registry, connects to the enabled downstream servers (stdio or remote HTTP/SSE), and routes tool calls to the right one. Tool names are namespaced per server (`stripe__list_charges`) so they never collide. ``` AI client (Cursor / Claude / Codex / Antigravity / ...) │ stdio MCP ▼ conduit-gateway ──reads──► registry.json + OS keychain │ routes tools/calls ▼ downstream MCP servers (Stripe, Supabase, GitHub, ...) ``` The registry is the shared source of truth; the gateway watches it and rebuilds live, so toggles and new credentials take effect without restarting the client. ## Supported clients Cursor, Claude Desktop, Claude Code, Codex, Google Antigravity, VS Code, Windsurf, Gemini CLI, Cline, Roo Code, Warp, Amazon Q, Kiro, Zed, LM Studio, Jan, and Goose. Conduit detects each one, installs the gateway with one click, and can import a client's existing servers. ## Configuration Lazy discovery and the destructive-tool policy are global settings, stored in the registry and toggled in the app, so they apply to every client (lazy discovery is on by default). Per-client behavior is set via env vars on the gateway entry, written for you when you connect a client: - `CONDUIT_PROFILE=<name>` - scope this client to one profile's servers. Unset = the active profile. - `CONDUIT_DISCOVERY=lazy|full` - optional per-client override of the global lazy setting. Rarely needed; the gateway reads the registry default otherwise. - `CONDUIT_REGISTRY=<path>` - override the registry file location. Defaults to a stable per-user path so packaged and unpackaged clients agree. **Multiple accounts for the same service.** Credentials belong to a server, not a profile. To use, say, a work and a personal GitHub, add GitHub twice as two servers ("GitHub (work)", "GitHub (personal)"), authenticate each with its own account, and enable one in each profile. A client scoped to the work profile (`CONDUIT_PROFILE`) then only ever sees the work account. Tool names are namespaced per server, so the two never collide even in the same profile. ## Install Prebuilt installers are published on the [Releases](https://github.com/tsouth89/conduit/releases) page. Conduit runs on **Windows and macOS** (the macOS build is signed and notarized), with **Linux** in beta. On Linux, prefer the **`.deb`** (it links your system's WebKitGTK and is the most reliable package); the **AppImage** is a portable, no-root fallback but can clash with very new or virtualized graphics stacks (see Troubleshooting). To run from source, see Development below. The installer is not yet code signed. On **Windows**, SmartScreen may show "Windows protected your PC", click **More info → Run anyway**. On **macOS**, Gatekeeper may say the app "is damaged" or cannot be opened; right-click the app and choose **Open**, or run `xattr -dr com.apple.quarantine /Applications/Conduit.app`. See [docs/SIGNING.md](docs/SIGNING.md) for the signing plan. **Updating and uninstalling on Linux.** There is no graphical uninstaller, use the terminal. The package name is `conduit`. ```bash # Update to a newer version: just install the new .deb, it upgrades in place. sudo apt install ./Conduit_0.3.10_amd64.deb # Uninstall (keeps your config + saved secrets). sudo apt remove conduit # Uninstall and wipe app config too (secrets in the keyring stay). sudo apt purge conduit ``` If you used the **AppImage**, there's nothing to uninstall, just delete the `.AppImage` file. (On Windows use Add or Remove Programs; on macOS drag **Conduit.app** to the Trash.) ## Development Requires Node and the Rust toolchain. ```bash npm install npm run tauri dev # run the desktop app ``` Other useful commands: ```bash cargo test --manifest-path src-tauri/Cargo.toml # Rust unit tests (lib + gateway) # Build the gateway binary. Required when running from source: AI clients spawn # this binary directly, so without it a connected client reports "not found". # (Packaged releases bundle it, so installed users never need this.) npm run build:gateway # Build a Windows installer (NSIS) with the gateway bundled. npm run tauri:bundle ``` The frontend is typechecked with `npx tsc --noEmit`. ## Troubleshooting - **OAuth opens a blank page (macOS).** The OAuth flow redirects back to a local `http://127.0.0.1` callback. Safari can silently block that redirect, so the sign-in page renders blank. Set **Chrome or Brave** as your default browser (or paste an access token instead). Complete one attempt at a time, an abandoned attempt keeps the callback port reserved for a few minutes and can cause a "state mismatch" on the next try. - **A client reports the gateway "was not found" (running from source).** Build the gateway binary once: `cd src-tauri && cargo build --bin conduit-gateway`. `npm run tauri dev` builds the app but not this separate binary; packaged releases bundle it, so installed users never hit this. - **Repeated macOS keychain prompts / "could not read secret from the keychain" in dev.** An unsigned dev build gets an unstable code-signing identity, so the keychain re-prompts or denies reads. A signed release fixes this; it is a dev-only artifact. - **"could not read/store secret" on Linux.** Secret storage uses the freedesktop Secret Service (libsecret), provided by GNOME Keyring, KWallet, or similar. A headless box or a session without a running keyring daemon has nowhere to store secrets. Run Conduit in a desktop session, or install and unlock a keyring (e.g. `gnome-keyring`). - **macOS keychain prompt the first time the gateway runs.** When a client spawns the gateway and it reads a saved key, macOS asks for keychain access ("Conduit wants to use ..."). Click **Always Allow** once and it won't ask again. (The app and the gateway are separate signed binaries today; a future release will share keychain access so this prompt goes away.) - **VS Code: the conduit server doesn't start automatically.** VS Code may require you to click **Start Server** on the conduit MCP entry the first time, that's VS Code's own MCP handling, not Conduit. After that it reconnects on its own. - **Linux: the AppImage won't launch / no window (`EGL_BAD_PARAMETER`).** The AppImage bundles its own libraries, which can clash with a very new or virtualized graphics stack (e.g. VMware's `vmwgfx` driver, where the default EGL display fails). **Use the `.deb` instead**, it links your system's WebKitGTK and is the more reliable Linux package. If you must use the AppImage, try `EGL_PLATFORM=surfaceless ./Conduit_*.AppImage`, or in a VM enable 3D acceleration. (This is a packaging/GPU issue, not a Conduit bug; the `.deb` works where the AppImage doesn't.) ## Status Conduit is in active development. Working end to end: the gateway, lazy discovery, per-agent scoping, OAuth/key auth with live propagation, the catalog, client import/migrate, per-tool and destructive-tool governance, an audit log with latency/error stats, resources + prompts proxying, and a tool playground. See [docs/ROADMAP.md](docs/ROADMAP.md) for what is done and planned. ## Known issues - **Linux only, glib `VariantStrIter` soundness ([RUSTSEC-2024-0429](https://rustsec.org/advisories/RUSTSEC-2024-0429)).** Tauri's Linux webview stack pulls in `glib` 0.18 transitively (`wry → webkit2gtk → gtk 0.18 → glib 0.18`). The fix only exists in `glib` 0.20+, and the gtk-0.18 binding line, which is what Tauri 2 uses on Linux, hard-pins `glib = "^0.18"`, so the patched release cannot be selected without moving the whole webview stack. The bug is a soundness/null-deref crash (not remote code execution), is confined to the webview binding layer (Conduit never calls `VariantStrIter`), and does not affect the Windows or macOS builds. We are tracking the upstream move to a glib-0.20 stack and will apply a `[patch.crates-io]` backport if Linux crashes surface before then. ## License [MIT](LICENSE). The gateway and local manager are free and open source under an open-core model; planned team/enterprise features (shared/hosted gateway, RBAC/SSO, policy, audit export, secret-vault integrations) are a separate paid layer.