feat: add MCP server support with global library and per-project toggles

Add Model Context Protocol (MCP) server configuration support. Users can
define MCP servers globally (new sidebar tab) and enable them per-project.
Enabled servers are injected into containers as MCP_SERVERS_JSON env var
and merged into ~/.claude.json by the entrypoint.

Backend: McpServer model, McpStore (JSON + atomic writes), 4 CRUD commands,
container injection with fingerprint-based recreation detection.
Frontend: MCP sidebar tab, McpPanel/McpServerCard components, useMcpServers
hook, per-project MCP checkboxes in ProjectCard config.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/src-tauri/src/commands/mcp_commands.rs

@@ -0,0 +1,38 @@
+use tauri::State;
+
+use crate::models::McpServer;
+use crate::AppState;
+
+#[tauri::command]
+pub async fn list_mcp_servers(state: State<'_, AppState>) -> Result<Vec<McpServer>, String> {
+    Ok(state.mcp_store.list())
+}
+
+#[tauri::command]
+pub async fn add_mcp_server(
+    name: String,
+    state: State<'_, AppState>,
+) -> Result<McpServer, String> {
+    let name = name.trim().to_string();
+    if name.is_empty() {
+        return Err("MCP server name cannot be empty.".to_string());
+    }
+    let server = McpServer::new(name);
+    state.mcp_store.add(server)
+}
+
+#[tauri::command]
+pub async fn update_mcp_server(
+    server: McpServer,
+    state: State<'_, AppState>,
+) -> Result<McpServer, String> {
+    state.mcp_store.update(server)
+}
+
+#[tauri::command]
+pub async fn remove_mcp_server(
+    server_id: String,
+    state: State<'_, AppState>,
+) -> Result<(), String> {
+    state.mcp_store.remove(&server_id)
+}

app/src-tauri/src/commands/mod.rs

@@ -1,4 +1,5 @@
 pub mod docker_commands;
+pub mod mcp_commands;
 pub mod project_commands;
 pub mod settings_commands;
 pub mod terminal_commands;

app/src-tauri/src/commands/project_commands.rs

@@ -1,7 +1,7 @@
 use tauri::{Emitter, State};
 
 use crate::docker;
-use crate::models::{container_config, AuthMode, Project, ProjectPath, ProjectStatus};
+use crate::models::{container_config, AuthMode, McpServer, Project, ProjectPath, ProjectStatus};
 use crate::storage::secure;
 use crate::AppState;
 
@@ -142,6 +142,12 @@ pub async fn start_project_container(
     let settings = state.settings_store.get();
     let image_name = container_config::resolve_image_name(&settings.image_source, &settings.custom_image_name);
 
+    // Resolve enabled MCP servers for this project
+    let all_mcp_servers = state.mcp_store.list();
+    let enabled_mcp: Vec<McpServer> = project.enabled_mcp_servers.iter()
+        .filter_map(|id| all_mcp_servers.iter().find(|s| &s.id == id).cloned())
+        .collect();
+
     // Validate auth mode requirements
     if project.auth_mode == AuthMode::Bedrock {
         let bedrock = project.bedrock_config.as_ref()
@@ -180,6 +186,7 @@ pub async fn start_project_container(
                 settings.global_claude_instructions.as_deref(),
                 &settings.global_custom_env_vars,
                 settings.timezone.as_deref(),
+                &enabled_mcp,
             ).await.unwrap_or(false);
 
             if needs_recreate {
@@ -210,6 +217,7 @@ pub async fn start_project_container(
                     settings.global_claude_instructions.as_deref(),
                     &settings.global_custom_env_vars,
                     settings.timezone.as_deref(),
+                    &enabled_mcp,
                 ).await?;
                 emit_progress(&app_handle, &project_id, "Starting container...");
                 docker::start_container(&new_id).await?;
@@ -241,6 +249,7 @@ pub async fn start_project_container(
                 settings.global_claude_instructions.as_deref(),
                 &settings.global_custom_env_vars,
                 settings.timezone.as_deref(),
+                &enabled_mcp,
             ).await?;
             emit_progress(&app_handle, &project_id, "Starting container...");
             docker::start_container(&new_id).await?;

app/src-tauri/src/docker/container.rs

@@ -9,7 +9,7 @@ use std::collections::hash_map::DefaultHasher;
 use std::hash::{Hash, Hasher};
 
 use super::client::get_docker;
-use crate::models::{AuthMode, BedrockAuthMethod, ContainerInfo, EnvVar, GlobalAwsSettings, PortMapping, Project, ProjectPath};
+use crate::models::{AuthMode, BedrockAuthMethod, ContainerInfo, EnvVar, GlobalAwsSettings, McpServer, McpTransportType, PortMapping, Project, ProjectPath};
 
 const SCHEDULER_INSTRUCTIONS: &str = r#"## Scheduled Tasks
 
@@ -176,6 +176,61 @@ fn compute_ports_fingerprint(port_mappings: &[PortMapping]) -> String {
     format!("{:x}", hasher.finish())
 }
 
+/// Build the JSON value for MCP servers config to be injected into ~/.claude.json.
+/// Produces `{"mcpServers": {"name": {"type": "stdio", ...}, ...}}`.
+fn build_mcp_servers_json(servers: &[McpServer]) -> String {
+    let mut mcp_map = serde_json::Map::new();
+    for server in servers {
+        let mut entry = serde_json::Map::new();
+        match server.transport_type {
+            McpTransportType::Stdio => {
+                entry.insert("type".to_string(), serde_json::json!("stdio"));
+                if let Some(ref cmd) = server.command {
+                    entry.insert("command".to_string(), serde_json::json!(cmd));
+                }
+                if !server.args.is_empty() {
+                    entry.insert("args".to_string(), serde_json::json!(server.args));
+                }
+                if !server.env.is_empty() {
+                    entry.insert("env".to_string(), serde_json::json!(server.env));
+                }
+            }
+            McpTransportType::Http => {
+                entry.insert("type".to_string(), serde_json::json!("http"));
+                if let Some(ref url) = server.url {
+                    entry.insert("url".to_string(), serde_json::json!(url));
+                }
+                if !server.headers.is_empty() {
+                    entry.insert("headers".to_string(), serde_json::json!(server.headers));
+                }
+            }
+            McpTransportType::Sse => {
+                entry.insert("type".to_string(), serde_json::json!("sse"));
+                if let Some(ref url) = server.url {
+                    entry.insert("url".to_string(), serde_json::json!(url));
+                }
+                if !server.headers.is_empty() {
+                    entry.insert("headers".to_string(), serde_json::json!(server.headers));
+                }
+            }
+        }
+        mcp_map.insert(server.name.clone(), serde_json::Value::Object(entry));
+    }
+    let wrapper = serde_json::json!({ "mcpServers": mcp_map });
+    serde_json::to_string(&wrapper).unwrap_or_default()
+}
+
+/// Compute a fingerprint for MCP server configuration so we can detect changes.
+fn compute_mcp_fingerprint(servers: &[McpServer]) -> String {
+    if servers.is_empty() {
+        return String::new();
+    }
+    let json = build_mcp_servers_json(servers);
+    let mut hasher = DefaultHasher::new();
+    json.hash(&mut hasher);
+    format!("{:x}", hasher.finish())
+}
+
 pub async fn find_existing_container(project: &Project) -> Result<Option<String>, String> {
     let docker = get_docker()?;
     let container_name = project.container_name();
@@ -215,6 +270,7 @@ pub async fn create_container(
     global_claude_instructions: Option<&str>,
     global_custom_env_vars: &[EnvVar],
     timezone: Option<&str>,
+    mcp_servers: &[McpServer],
 ) -> Result<String, String> {
     let docker = get_docker()?;
     let container_name = project.container_name();
@@ -355,6 +411,12 @@ pub async fn create_container(
         env_vars.push(format!("CLAUDE_INSTRUCTIONS={}", instructions));
     }
 
+    // MCP servers config
+    if !mcp_servers.is_empty() {
+        let mcp_json = build_mcp_servers_json(mcp_servers);
+        env_vars.push(format!("MCP_SERVERS_JSON={}", mcp_json));
+    }
+
     let mut mounts: Vec<Mount> = Vec::new();
 
     // Project directories -> /workspace/{mount_name}
@@ -474,6 +536,7 @@ pub async fn create_container(
     labels.insert("triple-c.ports-fingerprint".to_string(), compute_ports_fingerprint(&project.port_mappings));
     labels.insert("triple-c.image".to_string(), image_name.to_string());
     labels.insert("triple-c.timezone".to_string(), timezone.unwrap_or("").to_string());
+    labels.insert("triple-c.mcp-fingerprint".to_string(), compute_mcp_fingerprint(mcp_servers));
 
     let host_config = HostConfig {
         mounts: Some(mounts),
@@ -637,6 +700,7 @@ pub async fn container_needs_recreation(
     global_claude_instructions: Option<&str>,
     global_custom_env_vars: &[EnvVar],
     timezone: Option<&str>,
+    mcp_servers: &[McpServer],
 ) -> Result<bool, String> {
     let docker = get_docker()?;
     let info = docker
@@ -801,6 +865,14 @@ pub async fn container_needs_recreation(
         return Ok(true);
     }
 
+    // ── MCP servers fingerprint ─────────────────────────────────────────
+    let expected_mcp_fp = compute_mcp_fingerprint(mcp_servers);
+    let container_mcp_fp = get_label("triple-c.mcp-fingerprint").unwrap_or_default();
+    if container_mcp_fp != expected_mcp_fp {
+        log::info!("MCP servers fingerprint mismatch (container={:?}, expected={:?})", container_mcp_fp, expected_mcp_fp);
+        return Ok(true);
+    }
+
     Ok(false)
 }
 

app/src-tauri/src/lib.rs

@@ -7,11 +7,13 @@ mod storage;
 use docker::exec::ExecSessionManager;
 use storage::projects_store::ProjectsStore;
 use storage::settings_store::SettingsStore;
+use storage::mcp_store::McpStore;
 use tauri::Manager;
 
 pub struct AppState {
     pub projects_store: ProjectsStore,
     pub settings_store: SettingsStore,
+    pub mcp_store: McpStore,
     pub exec_manager: ExecSessionManager,
 }
 
@@ -32,6 +34,13 @@ pub fn run() {
             panic!("Failed to initialize settings store: {}", e);
         }
     };
+    let mcp_store = match McpStore::new() {
+        Ok(s) => s,
+        Err(e) => {
+            log::error!("Failed to initialize MCP store: {}", e);
+            panic!("Failed to initialize MCP store: {}", e);
+        }
+    };
 
     tauri::Builder::default()
         .plugin(tauri_plugin_store::Builder::default().build())
@@ -40,6 +49,7 @@ pub fn run() {
         .manage(AppState {
             projects_store,
             settings_store,
+            mcp_store,
             exec_manager: ExecSessionManager::new(),
         })
         .setup(|app| {
@@ -91,6 +101,11 @@ pub fn run() {
             commands::terminal_commands::terminal_resize,
             commands::terminal_commands::close_terminal_session,
             commands::terminal_commands::paste_image_to_terminal,
+            // MCP
+            commands::mcp_commands::list_mcp_servers,
+            commands::mcp_commands::add_mcp_server,
+            commands::mcp_commands::update_mcp_server,
+            commands::mcp_commands::remove_mcp_server,
             // Updates
             commands::update_commands::get_app_version,
             commands::update_commands::check_for_updates,

app/src-tauri/src/models/mcp_server.rs

@@ -0,0 +1,52 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+#[serde(rename_all = "snake_case")]
+pub enum McpTransportType {
+    Stdio,
+    Http,
+    Sse,
+}
+
+impl Default for McpTransportType {
+    fn default() -> Self {
+        Self::Stdio
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct McpServer {
+    pub id: String,
+    pub name: String,
+    #[serde(default)]
+    pub transport_type: McpTransportType,
+    pub command: Option<String>,
+    #[serde(default)]
+    pub args: Vec<String>,
+    #[serde(default)]
+    pub env: HashMap<String, String>,
+    pub url: Option<String>,
+    #[serde(default)]
+    pub headers: HashMap<String, String>,
+    pub created_at: String,
+    pub updated_at: String,
+}
+
+impl McpServer {
+    pub fn new(name: String) -> Self {
+        let now = chrono::Utc::now().to_rfc3339();
+        Self {
+            id: uuid::Uuid::new_v4().to_string(),
+            name,
+            transport_type: McpTransportType::default(),
+            command: None,
+            args: Vec::new(),
+            env: HashMap::new(),
+            url: None,
+            headers: HashMap::new(),
+            created_at: now.clone(),
+            updated_at: now,
+        }
+    }
+}

app/src-tauri/src/models/mod.rs

@@ -2,8 +2,10 @@ pub mod project;
 pub mod container_config;
 pub mod app_settings;
 pub mod update_info;
+pub mod mcp_server;
 
 pub use project::*;
 pub use container_config::*;
 pub use app_settings::*;
 pub use update_info::*;
+pub use mcp_server::*;

app/src-tauri/src/models/project.rs

@@ -45,6 +45,8 @@ pub struct Project {
     pub port_mappings: Vec<PortMapping>,
     #[serde(default)]
     pub claude_instructions: Option<String>,
+    #[serde(default)]
+    pub enabled_mcp_servers: Vec<String>,
     pub created_at: String,
     pub updated_at: String,
 }
@@ -130,6 +132,7 @@ impl Project {
             custom_env_vars: Vec::new(),
             port_mappings: Vec::new(),
             claude_instructions: None,
+            enabled_mcp_servers: Vec::new(),
             created_at: now.clone(),
             updated_at: now,
         }

app/src-tauri/src/storage/mcp_store.rs

@@ -0,0 +1,106 @@
+use std::fs;
+use std::path::PathBuf;
+use std::sync::Mutex;
+
+use crate::models::McpServer;
+
+pub struct McpStore {
+    servers: Mutex<Vec<McpServer>>,
+    file_path: PathBuf,
+}
+
+impl McpStore {
+    pub fn new() -> Result<Self, String> {
+        let data_dir = dirs::data_dir()
+            .ok_or_else(|| "Could not determine data directory. Set XDG_DATA_HOME on Linux.".to_string())?
+            .join("triple-c");
+
+        fs::create_dir_all(&data_dir).ok();
+
+        let file_path = data_dir.join("mcp_servers.json");
+
+        let servers = if file_path.exists() {
+            match fs::read_to_string(&file_path) {
+                Ok(data) => {
+                    match serde_json::from_str::<Vec<McpServer>>(&data) {
+                        Ok(parsed) => parsed,
+                        Err(e) => {
+                            log::error!("Failed to parse mcp_servers.json: {}. Starting with empty list.", e);
+                            let backup = file_path.with_extension("json.bak");
+                            if let Err(be) = fs::copy(&file_path, &backup) {
+                                log::error!("Failed to back up corrupted mcp_servers.json: {}", be);
+                            }
+                            Vec::new()
+                        }
+                    }
+                }
+                Err(e) => {
+                    log::error!("Failed to read mcp_servers.json: {}", e);
+                    Vec::new()
+                }
+            }
+        } else {
+            Vec::new()
+        };
+
+        Ok(Self {
+            servers: Mutex::new(servers),
+            file_path,
+        })
+    }
+
+    fn lock(&self) -> std::sync::MutexGuard<'_, Vec<McpServer>> {
+        self.servers.lock().unwrap_or_else(|e| e.into_inner())
+    }
+
+    fn save(&self, servers: &[McpServer]) -> Result<(), String> {
+        let data = serde_json::to_string_pretty(servers)
+            .map_err(|e| format!("Failed to serialize MCP servers: {}", e))?;
+
+        // Atomic write: write to temp file, then rename
+        let tmp_path = self.file_path.with_extension("json.tmp");
+        fs::write(&tmp_path, data)
+            .map_err(|e| format!("Failed to write temp MCP servers file: {}", e))?;
+        fs::rename(&tmp_path, &self.file_path)
+            .map_err(|e| format!("Failed to rename MCP servers file: {}", e))?;
+        Ok(())
+    }
+
+    pub fn list(&self) -> Vec<McpServer> {
+        self.lock().clone()
+    }
+
+    pub fn get(&self, id: &str) -> Option<McpServer> {
+        self.lock().iter().find(|s| s.id == id).cloned()
+    }
+
+    pub fn add(&self, server: McpServer) -> Result<McpServer, String> {
+        let mut servers = self.lock();
+        let cloned = server.clone();
+        servers.push(server);
+        self.save(&servers)?;
+        Ok(cloned)
+    }
+
+    pub fn update(&self, updated: McpServer) -> Result<McpServer, String> {
+        let mut servers = self.lock();
+        if let Some(s) = servers.iter_mut().find(|s| s.id == updated.id) {
+            *s = updated.clone();
+            self.save(&servers)?;
+            Ok(updated)
+        } else {
+            Err(format!("MCP server {} not found", updated.id))
+        }
+    }
+
+    pub fn remove(&self, id: &str) -> Result<(), String> {
+        let mut servers = self.lock();
+        let initial_len = servers.len();
+        servers.retain(|s| s.id != id);
+        if servers.len() == initial_len {
+            return Err(format!("MCP server {} not found", id));
+        }
+        self.save(&servers)?;
+        Ok(())
+    }
+}

app/src-tauri/src/storage/mod.rs

@@ -1,7 +1,9 @@
 pub mod projects_store;
 pub mod secure;
 pub mod settings_store;
+pub mod mcp_store;
 
 pub use projects_store::*;
 pub use secure::*;
 pub use settings_store::*;
+pub use mcp_store::*;

app/src/App.tsx

@@ -7,6 +7,7 @@ import TerminalView from "./components/terminal/TerminalView";
 import { useDocker } from "./hooks/useDocker";
 import { useSettings } from "./hooks/useSettings";
 import { useProjects } from "./hooks/useProjects";
+import { useMcpServers } from "./hooks/useMcpServers";
 import { useUpdates } from "./hooks/useUpdates";
 import { useAppState } from "./store/appState";
 
@@ -14,6 +15,7 @@ export default function App() {
   const { checkDocker, checkImage, startDockerPolling } = useDocker();
   const { loadSettings } = useSettings();
   const { refresh } = useProjects();
+  const { refresh: refreshMcp } = useMcpServers();
   const { loadVersion, checkForUpdates, startPeriodicCheck } = useUpdates();
   const { sessions, activeSessionId } = useAppState(
     useShallow(s => ({ sessions: s.sessions, activeSessionId: s.activeSessionId }))
@@ -31,6 +33,7 @@ export default function App() {
       }
     });
     refresh();
+    refreshMcp();
 
     // Update detection
     loadVersion();

app/src/components/layout/Sidebar.test.tsx

@@ -19,6 +19,9 @@ vi.mock("../projects/ProjectList", () => ({
 vi.mock("../settings/SettingsPanel", () => ({
   default: () => <div data-testid="settings-panel">SettingsPanel</div>,
 }));
+vi.mock("../mcp/McpPanel", () => ({
+  default: () => <div data-testid="mcp-panel">McpPanel</div>,
+}));
 
 describe("Sidebar", () => {
   beforeEach(() => {

app/src/components/layout/Sidebar.tsx

@@ -1,6 +1,7 @@
 import { useShallow } from "zustand/react/shallow";
 import { useAppState } from "../../store/appState";
 import ProjectList from "../projects/ProjectList";
+import McpPanel from "../mcp/McpPanel";
 import SettingsPanel from "../settings/SettingsPanel";
 
 export default function Sidebar() {
@@ -8,35 +9,37 @@ export default function Sidebar() {
     useShallow(s => ({ sidebarView: s.sidebarView, setSidebarView: s.setSidebarView }))
   );
 
+  const tabCls = (view: typeof sidebarView) =>
+    `flex-1 px-3 py-2 text-sm font-medium transition-colors ${
+      sidebarView === view
+        ? "text-[var(--accent)] border-b-2 border-[var(--accent)]"
+        : "text-[var(--text-secondary)] hover:text-[var(--text-primary)]"
+    }`;
+
   return (
     <div className="flex flex-col h-full w-[25%] min-w-56 max-w-80 bg-[var(--bg-secondary)] border border-[var(--border-color)] rounded-lg overflow-hidden">
       {/* Nav tabs */}
       <div className="flex border-b border-[var(--border-color)]">
-        <button
+        <button onClick={() => setSidebarView("projects")} className={tabCls("projects")}>
-          onClick={() => setSidebarView("projects")}
-          className={`flex-1 px-3 py-2 text-sm font-medium transition-colors ${
-            sidebarView === "projects"
-              ? "text-[var(--accent)] border-b-2 border-[var(--accent)]"
-              : "text-[var(--text-secondary)] hover:text-[var(--text-primary)]"
-          }`}
-        >
           Projects
         </button>
-        <button
+        <button onClick={() => setSidebarView("mcp")} className={tabCls("mcp")}>
-          onClick={() => setSidebarView("settings")}
+          MCP
-          className={`flex-1 px-3 py-2 text-sm font-medium transition-colors ${
+        </button>
-            sidebarView === "settings"
+        <button onClick={() => setSidebarView("settings")} className={tabCls("settings")}>
-              ? "text-[var(--accent)] border-b-2 border-[var(--accent)]"
-              : "text-[var(--text-secondary)] hover:text-[var(--text-primary)]"
-          }`}
-        >
           Settings
         </button>
       </div>
 
       {/* Content */}
       <div className="flex-1 overflow-y-auto overflow-x-hidden p-1 min-w-0">
-        {sidebarView === "projects" ? <ProjectList /> : <SettingsPanel />}
+        {sidebarView === "projects" ? (
+          <ProjectList />
+        ) : sidebarView === "mcp" ? (
+          <McpPanel />
+        ) : (
+          <SettingsPanel />
+        )}
       </div>
     </div>
   );

app/src/components/mcp/McpPanel.tsx

@@ -0,0 +1,76 @@
+import { useState, useEffect } from "react";
+import { useMcpServers } from "../../hooks/useMcpServers";
+import McpServerCard from "./McpServerCard";
+
+export default function McpPanel() {
+  const { mcpServers, refresh, add, update, remove } = useMcpServers();
+  const [newName, setNewName] = useState("");
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    refresh();
+  }, []); // eslint-disable-line react-hooks/exhaustive-deps
+
+  const handleAdd = async () => {
+    const name = newName.trim();
+    if (!name) return;
+    setError(null);
+    try {
+      await add(name);
+      setNewName("");
+    } catch (e) {
+      setError(String(e));
+    }
+  };
+
+  return (
+    <div className="space-y-3 p-2">
+      <div>
+        <h2 className="text-sm font-semibold text-[var(--text-primary)]">MCP Servers</h2>
+        <p className="text-xs text-[var(--text-secondary)] mt-0.5">
+          Define MCP servers globally, then enable them per-project.
+        </p>
+      </div>
+
+      {/* Add new server */}
+      <div className="flex gap-1">
+        <input
+          value={newName}
+          onChange={(e) => setNewName(e.target.value)}
+          onKeyDown={(e) => { if (e.key === "Enter") handleAdd(); }}
+          placeholder="Server name..."
+          className="flex-1 px-2 py-1 bg-[var(--bg-primary)] border border-[var(--border-color)] rounded text-xs text-[var(--text-primary)] focus:outline-none focus:border-[var(--accent)]"
+        />
+        <button
+          onClick={handleAdd}
+          disabled={!newName.trim()}
+          className="px-3 py-1 text-xs bg-[var(--accent)] text-white rounded hover:bg-[var(--accent-hover)] disabled:opacity-50 transition-colors"
+        >
+          Add
+        </button>
+      </div>
+
+      {error && (
+        <div className="text-xs text-[var(--error)]">{error}</div>
+      )}
+
+      {/* Server list */}
+      <div className="space-y-2">
+        {mcpServers.length === 0 ? (
+          <p className="text-xs text-[var(--text-secondary)] italic">
+            No MCP servers configured.
+          </p>
+        ) : (
+          mcpServers.map((server) => (
+            <McpServerCard
+              key={server.id}
+              server={server}
+              onUpdate={update}
+              onRemove={remove}
+            />
+          ))
+        )}
+      </div>
+    </div>
+  );
+}

app/src/components/mcp/McpServerCard.tsx

@@ -0,0 +1,262 @@
+import { useState, useEffect } from "react";
+import type { McpServer, McpTransportType } from "../../lib/types";
+
+interface Props {
+  server: McpServer;
+  onUpdate: (server: McpServer) => Promise<McpServer | void>;
+  onRemove: (id: string) => Promise<void>;
+}
+
+export default function McpServerCard({ server, onUpdate, onRemove }: Props) {
+  const [expanded, setExpanded] = useState(false);
+  const [name, setName] = useState(server.name);
+  const [transportType, setTransportType] = useState<McpTransportType>(server.transport_type);
+  const [command, setCommand] = useState(server.command ?? "");
+  const [args, setArgs] = useState(server.args.join(" "));
+  const [envPairs, setEnvPairs] = useState<[string, string][]>(Object.entries(server.env));
+  const [url, setUrl] = useState(server.url ?? "");
+  const [headerPairs, setHeaderPairs] = useState<[string, string][]>(Object.entries(server.headers));
+
+  useEffect(() => {
+    setName(server.name);
+    setTransportType(server.transport_type);
+    setCommand(server.command ?? "");
+    setArgs(server.args.join(" "));
+    setEnvPairs(Object.entries(server.env));
+    setUrl(server.url ?? "");
+    setHeaderPairs(Object.entries(server.headers));
+  }, [server]);
+
+  const saveServer = async (patch: Partial<McpServer>) => {
+    try {
+      await onUpdate({ ...server, ...patch });
+    } catch (err) {
+      console.error("Failed to update MCP server:", err);
+    }
+  };
+
+  const handleNameBlur = () => {
+    if (name !== server.name) saveServer({ name });
+  };
+
+  const handleTransportChange = (t: McpTransportType) => {
+    setTransportType(t);
+    saveServer({ transport_type: t });
+  };
+
+  const handleCommandBlur = () => {
+    saveServer({ command: command || null });
+  };
+
+  const handleArgsBlur = () => {
+    const parsed = args.trim() ? args.trim().split(/\s+/) : [];
+    saveServer({ args: parsed });
+  };
+
+  const handleUrlBlur = () => {
+    saveServer({ url: url || null });
+  };
+
+  const saveEnv = (pairs: [string, string][]) => {
+    const env: Record<string, string> = {};
+    for (const [k, v] of pairs) {
+      if (k.trim()) env[k.trim()] = v;
+    }
+    saveServer({ env });
+  };
+
+  const saveHeaders = (pairs: [string, string][]) => {
+    const headers: Record<string, string> = {};
+    for (const [k, v] of pairs) {
+      if (k.trim()) headers[k.trim()] = v;
+    }
+    saveServer({ headers });
+  };
+
+  const inputCls = "w-full px-2 py-1 bg-[var(--bg-primary)] border border-[var(--border-color)] rounded text-xs text-[var(--text-primary)] focus:outline-none focus:border-[var(--accent)]";
+
+  const transportBadge = {
+    stdio: "Stdio",
+    http: "HTTP",
+    sse: "SSE",
+  }[transportType];
+
+  return (
+    <div className="border border-[var(--border-color)] rounded bg-[var(--bg-primary)]">
+      {/* Header */}
+      <div className="flex items-center gap-2 px-3 py-2">
+        <button
+          onClick={() => setExpanded(!expanded)}
+          className="flex-1 flex items-center gap-2 text-left min-w-0"
+        >
+          <span className="text-xs text-[var(--text-secondary)]">{expanded ? "\u25BC" : "\u25B6"}</span>
+          <span className="text-sm font-medium truncate">{server.name}</span>
+          <span className="text-xs px-1.5 py-0.5 rounded bg-[var(--bg-secondary)] text-[var(--text-secondary)]">
+            {transportBadge}
+          </span>
+        </button>
+        <button
+          onClick={() => { if (confirm(`Remove MCP server "${server.name}"?`)) onRemove(server.id); }}
+          className="text-xs px-2 py-0.5 text-[var(--error)] hover:bg-[var(--bg-secondary)] rounded transition-colors"
+        >
+          Remove
+        </button>
+      </div>
+
+      {/* Expanded config */}
+      {expanded && (
+        <div className="px-3 pb-3 space-y-2 border-t border-[var(--border-color)] pt-2">
+          {/* Name */}
+          <div>
+            <label className="block text-xs text-[var(--text-secondary)] mb-0.5">Name</label>
+            <input
+              value={name}
+              onChange={(e) => setName(e.target.value)}
+              onBlur={handleNameBlur}
+              className={inputCls}
+            />
+          </div>
+
+          {/* Transport type */}
+          <div>
+            <label className="block text-xs text-[var(--text-secondary)] mb-0.5">Transport</label>
+            <div className="flex items-center gap-1">
+              {(["stdio", "http", "sse"] as McpTransportType[]).map((t) => (
+                <button
+                  key={t}
+                  onClick={() => handleTransportChange(t)}
+                  className={`px-2 py-0.5 text-xs rounded transition-colors ${
+                    transportType === t
+                      ? "bg-[var(--accent)] text-white"
+                      : "text-[var(--text-secondary)] hover:text-[var(--text-primary)] hover:bg-[var(--bg-secondary)]"
+                  }`}
+                >
+                  {t === "stdio" ? "Stdio" : t === "http" ? "HTTP" : "SSE"}
+                </button>
+              ))}
+            </div>
+          </div>
+
+          {/* Stdio fields */}
+          {transportType === "stdio" && (
+            <>
+              <div>
+                <label className="block text-xs text-[var(--text-secondary)] mb-0.5">Command</label>
+                <input
+                  value={command}
+                  onChange={(e) => setCommand(e.target.value)}
+                  onBlur={handleCommandBlur}
+                  placeholder="npx"
+                  className={inputCls}
+                />
+              </div>
+              <div>
+                <label className="block text-xs text-[var(--text-secondary)] mb-0.5">Arguments (space-separated)</label>
+                <input
+                  value={args}
+                  onChange={(e) => setArgs(e.target.value)}
+                  onBlur={handleArgsBlur}
+                  placeholder="-y @modelcontextprotocol/server-filesystem /path"
+                  className={inputCls}
+                />
+              </div>
+              <KeyValueEditor
+                label="Environment Variables"
+                pairs={envPairs}
+                onChange={(pairs) => { setEnvPairs(pairs); }}
+                onSave={saveEnv}
+              />
+            </>
+          )}
+
+          {/* HTTP/SSE fields */}
+          {(transportType === "http" || transportType === "sse") && (
+            <>
+              <div>
+                <label className="block text-xs text-[var(--text-secondary)] mb-0.5">URL</label>
+                <input
+                  value={url}
+                  onChange={(e) => setUrl(e.target.value)}
+                  onBlur={handleUrlBlur}
+                  placeholder="http://localhost:3000/mcp"
+                  className={inputCls}
+                />
+              </div>
+              <KeyValueEditor
+                label="Headers"
+                pairs={headerPairs}
+                onChange={(pairs) => { setHeaderPairs(pairs); }}
+                onSave={saveHeaders}
+              />
+            </>
+          )}
+        </div>
+      )}
+    </div>
+  );
+}
+
+function KeyValueEditor({
+  label,
+  pairs,
+  onChange,
+  onSave,
+}: {
+  label: string;
+  pairs: [string, string][];
+  onChange: (pairs: [string, string][]) => void;
+  onSave: (pairs: [string, string][]) => void;
+}) {
+  const inputCls = "flex-1 min-w-0 px-2 py-1 bg-[var(--bg-primary)] border border-[var(--border-color)] rounded text-xs text-[var(--text-primary)] focus:outline-none focus:border-[var(--accent)]";
+
+  return (
+    <div>
+      <label className="block text-xs text-[var(--text-secondary)] mb-0.5">{label}</label>
+      {pairs.map(([key, value], i) => (
+        <div key={i} className="flex gap-1 items-center mb-1">
+          <input
+            value={key}
+            onChange={(e) => {
+              const updated = [...pairs] as [string, string][];
+              updated[i] = [e.target.value, value];
+              onChange(updated);
+            }}
+            onBlur={() => onSave(pairs)}
+            placeholder="KEY"
+            className={inputCls}
+          />
+          <span className="text-xs text-[var(--text-secondary)]">=</span>
+          <input
+            value={value}
+            onChange={(e) => {
+              const updated = [...pairs] as [string, string][];
+              updated[i] = [key, e.target.value];
+              onChange(updated);
+            }}
+            onBlur={() => onSave(pairs)}
+            placeholder="value"
+            className={inputCls}
+          />
+          <button
+            onClick={() => {
+              const updated = pairs.filter((_, j) => j !== i);
+              onChange(updated);
+              onSave(updated);
+            }}
+            className="flex-shrink-0 px-1.5 py-1 text-xs text-[var(--error)] hover:bg-[var(--bg-secondary)] rounded transition-colors"
+          >
+            x
+          </button>
+        </div>
+      ))}
+      <button
+        onClick={() => {
+          onChange([...pairs, ["", ""]]);
+        }}
+        className="text-xs text-[var(--accent)] hover:text-[var(--accent-hover)] transition-colors"
+      >
+        + Add
+      </button>
+    </div>
+  );
+}

app/src/components/projects/ProjectCard.test.tsx

@@ -31,6 +31,16 @@ vi.mock("../../hooks/useTerminal", () => ({
   }),
 }));
 
+vi.mock("../../hooks/useMcpServers", () => ({
+  useMcpServers: () => ({
+    mcpServers: [],
+    refresh: vi.fn(),
+    add: vi.fn(),
+    update: vi.fn(),
+    remove: vi.fn(),
+  }),
+}));
+
 let mockSelectedProjectId: string | null = null;
 vi.mock("../../store/appState", () => ({
   useAppState: vi.fn((selector) =>
@@ -55,7 +65,9 @@ const mockProject: Project = {
   git_user_name: null,
   git_user_email: null,
   custom_env_vars: [],
+  port_mappings: [],
   claude_instructions: null,
+  enabled_mcp_servers: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };

app/src/components/projects/ProjectCard.tsx

@@ -3,6 +3,7 @@ import { open } from "@tauri-apps/plugin-dialog";
 import { listen } from "@tauri-apps/api/event";
 import type { Project, ProjectPath, AuthMode, BedrockConfig, BedrockAuthMethod } from "../../lib/types";
 import { useProjects } from "../../hooks/useProjects";
+import { useMcpServers } from "../../hooks/useMcpServers";
 import { useTerminal } from "../../hooks/useTerminal";
 import { useAppState } from "../../store/appState";
 import EnvVarsModal from "./EnvVarsModal";
@@ -18,6 +19,7 @@ export default function ProjectCard({ project }: Props) {
   const selectedProjectId = useAppState(s => s.selectedProjectId);
   const setSelectedProject = useAppState(s => s.setSelectedProject);
   const { start, stop, rebuild, remove, update } = useProjects();
+  const { mcpServers } = useMcpServers();
   const { open: openTerminal } = useTerminal();
   const [loading, setLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
@@ -613,6 +615,40 @@ export default function ProjectCard({ project }: Props) {
                 </button>
               </div>
 
+              {/* MCP Servers */}
+              {mcpServers.length > 0 && (
+                <div>
+                  <label className="block text-xs text-[var(--text-secondary)] mb-1">MCP Servers</label>
+                  <div className="space-y-1">
+                    {mcpServers.map((server) => {
+                      const enabled = project.enabled_mcp_servers.includes(server.id);
+                      return (
+                        <label key={server.id} className="flex items-center gap-2 cursor-pointer">
+                          <input
+                            type="checkbox"
+                            checked={enabled}
+                            disabled={!isStopped}
+                            onChange={async () => {
+                              const updated = enabled
+                                ? project.enabled_mcp_servers.filter((id) => id !== server.id)
+                                : [...project.enabled_mcp_servers, server.id];
+                              try {
+                                await update({ ...project, enabled_mcp_servers: updated });
+                              } catch (err) {
+                                console.error("Failed to update MCP servers:", err);
+                              }
+                            }}
+                            className="rounded border-[var(--border-color)] disabled:opacity-50"
+                          />
+                          <span className="text-xs text-[var(--text-primary)]">{server.name}</span>
+                          <span className="text-xs text-[var(--text-secondary)]">({server.transport_type})</span>
+                        </label>
+                      );
+                    })}
+                  </div>
+                </div>
+              )}
+
               {/* Bedrock config */}
               {project.auth_mode === "bedrock" && (() => {
                 const bc = project.bedrock_config ?? defaultBedrockConfig;

app/src/hooks/useMcpServers.ts

@@ -0,0 +1,55 @@
+import { useCallback } from "react";
+import { useShallow } from "zustand/react/shallow";
+import { useAppState } from "../store/appState";
+import * as commands from "../lib/tauri-commands";
+import type { McpServer } from "../lib/types";
+
+export function useMcpServers() {
+  const {
+    mcpServers,
+    setMcpServers,
+    updateMcpServerInList,
+    removeMcpServerFromList,
+  } = useAppState(
+    useShallow(s => ({
+      mcpServers: s.mcpServers,
+      setMcpServers: s.setMcpServers,
+      updateMcpServerInList: s.updateMcpServerInList,
+      removeMcpServerFromList: s.removeMcpServerFromList,
+    }))
+  );
+
+  const refresh = useCallback(async () => {
+    const list = await commands.listMcpServers();
+    setMcpServers(list);
+  }, [setMcpServers]);
+
+  const add = useCallback(
+    async (name: string) => {
+      const server = await commands.addMcpServer(name);
+      const list = await commands.listMcpServers();
+      setMcpServers(list);
+      return server;
+    },
+    [setMcpServers],
+  );
+
+  const update = useCallback(
+    async (server: McpServer) => {
+      const updated = await commands.updateMcpServer(server);
+      updateMcpServerInList(updated);
+      return updated;
+    },
+    [updateMcpServerInList],
+  );
+
+  const remove = useCallback(
+    async (id: string) => {
+      await commands.removeMcpServer(id);
+      removeMcpServerFromList(id);
+    },
+    [removeMcpServerFromList],
+  );
+
+  return { mcpServers, refresh, add, update, remove };
+}

app/src/lib/tauri-commands.ts

@@ -1,5 +1,5 @@
 import { invoke } from "@tauri-apps/api/core";
-import type { Project, ProjectPath, ContainerInfo, SiblingContainer, AppSettings, UpdateInfo } from "./types";
+import type { Project, ProjectPath, ContainerInfo, SiblingContainer, AppSettings, UpdateInfo, McpServer } from "./types";
 
 // Docker
 export const checkDocker = () => invoke<boolean>("check_docker");
@@ -50,6 +50,15 @@ export const closeTerminalSession = (sessionId: string) =>
 export const pasteImageToTerminal = (sessionId: string, imageData: number[]) =>
   invoke<string>("paste_image_to_terminal", { sessionId, imageData });
 
+// MCP Servers
+export const listMcpServers = () => invoke<McpServer[]>("list_mcp_servers");
+export const addMcpServer = (name: string) =>
+  invoke<McpServer>("add_mcp_server", { name });
+export const updateMcpServer = (server: McpServer) =>
+  invoke<McpServer>("update_mcp_server", { server });
+export const removeMcpServer = (serverId: string) =>
+  invoke<void>("remove_mcp_server", { serverId });
+
 // Updates
 export const getAppVersion = () => invoke<string>("get_app_version");
 export const checkForUpdates = () =>

app/src/lib/types.ts

@@ -30,6 +30,7 @@ export interface Project {
   custom_env_vars: EnvVar[];
   port_mappings: PortMapping[];
   claude_instructions: string | null;
+  enabled_mcp_servers: string[];
   created_at: string;
   updated_at: string;
 }
@@ -115,3 +116,18 @@ export interface ReleaseAsset {
   browser_download_url: string;
   size: number;
 }
+
+export type McpTransportType = "stdio" | "http" | "sse";
+
+export interface McpServer {
+  id: string;
+  name: string;
+  transport_type: McpTransportType;
+  command: string | null;
+  args: string[];
+  env: Record<string, string>;
+  url: string | null;
+  headers: Record<string, string>;
+  created_at: string;
+  updated_at: string;
+}

app/src/store/appState.ts

@@ -1,5 +1,5 @@
 import { create } from "zustand";
-import type { Project, TerminalSession, AppSettings, UpdateInfo } from "../lib/types";
+import type { Project, TerminalSession, AppSettings, UpdateInfo, McpServer } from "../lib/types";
 
 interface AppState {
   // Projects
@@ -17,9 +17,15 @@ interface AppState {
   removeSession: (id: string) => void;
   setActiveSession: (id: string | null) => void;
 
+  // MCP servers
+  mcpServers: McpServer[];
+  setMcpServers: (servers: McpServer[]) => void;
+  updateMcpServerInList: (server: McpServer) => void;
+  removeMcpServerFromList: (id: string) => void;
+
   // UI state
-  sidebarView: "projects" | "settings";
+  sidebarView: "projects" | "mcp" | "settings";
-  setSidebarView: (view: "projects" | "settings") => void;
+  setSidebarView: (view: "projects" | "mcp" | "settings") => void;
   dockerAvailable: boolean | null;
   setDockerAvailable: (available: boolean | null) => void;
   imageExists: boolean | null;
@@ -75,6 +81,20 @@ export const useAppState = create<AppState>((set) => ({
     }),
   setActiveSession: (id) => set({ activeSessionId: id }),
 
+  // MCP servers
+  mcpServers: [],
+  setMcpServers: (servers) => set({ mcpServers: servers }),
+  updateMcpServerInList: (server) =>
+    set((state) => ({
+      mcpServers: state.mcpServers.map((s) =>
+        s.id === server.id ? server : s,
+      ),
+    })),
+  removeMcpServerFromList: (id) =>
+    set((state) => ({
+      mcpServers: state.mcpServers.filter((s) => s.id !== id),
+    })),
+
   // UI state
   sidebarView: "projects",
   setSidebarView: (view) => set({ sidebarView: view }),

container/entrypoint.sh

@@ -103,6 +103,27 @@ if [ -n "$CLAUDE_INSTRUCTIONS" ]; then
     unset CLAUDE_INSTRUCTIONS
 fi
 
+# ── MCP server configuration ────────────────────────────────────────────────
+# Merge MCP server config into ~/.claude.json (preserves existing keys like
+# OAuth tokens). Creates the file if it doesn't exist.
+if [ -n "$MCP_SERVERS_JSON" ]; then
+    CLAUDE_JSON="/home/claude/.claude.json"
+    if [ -f "$CLAUDE_JSON" ]; then
+        # Merge: existing config + MCP config (MCP keys override on conflict)
+        MERGED=$(jq -s '.[0] * .[1]' "$CLAUDE_JSON" <(printf '%s' "$MCP_SERVERS_JSON") 2>/dev/null)
+        if [ -n "$MERGED" ]; then
+            printf '%s\n' "$MERGED" > "$CLAUDE_JSON"
+        else
+            echo "entrypoint: warning — failed to merge MCP config into $CLAUDE_JSON"
+        fi
+    else
+        printf '%s\n' "$MCP_SERVERS_JSON" > "$CLAUDE_JSON"
+    fi
+    chown claude:claude "$CLAUDE_JSON"
+    chmod 600 "$CLAUDE_JSON"
+    unset MCP_SERVERS_JSON
+fi
+
 # ── Docker socket permissions ────────────────────────────────────────────────
 if [ -S /var/run/docker.sock ]; then
     DOCKER_GID=$(stat -c '%g' /var/run/docker.sock)