Add initial support for MCP Apps for select tools under Insiders

.github/workflows/code-scanning.yml

@@ -74,6 +74,18 @@ jobs:
           go-version: ${{ fromJSON(steps.resolve-environment.outputs.environment).configuration.go.version }}
           cache: false
 
+      - name: Set up Node.js
+        if: matrix.language == 'go'
+        uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+          cache: "npm"
+          cache-dependency-path: ui/package-lock.json
+
+      - name: Build UI
+        if: matrix.language == 'go'
+        run: script/build-ui
+
       - name: Autobuild
         uses: github/codeql-action/autobuild@v4
 

.github/workflows/docs-check.yml

@@ -16,6 +16,16 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v6
 
+    - name: Set up Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: "20"
+        cache: "npm"
+        cache-dependency-path: ui/package-lock.json
+
+    - name: Build UI
+      run: script/build-ui
+
     - name: Set up Go
       uses: actions/setup-go@v6
       with:

.github/workflows/go.yml

@@ -25,6 +25,17 @@ jobs:
       - name: Check out code
         uses: actions/checkout@v6
 
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+          cache: "npm"
+          cache-dependency-path: ui/package-lock.json
+
+      - name: Build UI
+        shell: bash
+        run: script/build-ui
+
       - name: Set up Go
         uses: actions/setup-go@v6
         with:
@@ -34,6 +45,7 @@ jobs:
         run: go mod tidy -diff
 
       - name: Run unit tests
+        shell: bash
         run: script/test
 
       - name: Build

.github/workflows/goreleaser.yml

@@ -16,6 +16,16 @@ jobs:
       - name: Check out code
         uses: actions/checkout@v6
 
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+          cache: "npm"
+          cache-dependency-path: ui/package-lock.json
+
+      - name: Build UI
+        run: script/build-ui
+
       - name: Set up Go
         uses: actions/setup-go@v6
         with:

.github/workflows/license-check.yml

@@ -32,6 +32,16 @@ jobs:
           GH_TOKEN: ${{ github.token }}
         run: gh pr checkout ${{ github.event.pull_request.number }}
 
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+          cache: "npm"
+          cache-dependency-path: ui/package-lock.json
+
+      - name: Build UI
+        run: script/build-ui
+
       - name: Set up Go
         uses: actions/setup-go@v6
         with:

.github/workflows/lint.yml

@@ -14,6 +14,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
+      - uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+          cache: "npm"
+          cache-dependency-path: ui/package-lock.json
+      - name: Build UI
+        run: script/build-ui
       - uses: actions/setup-go@v6
         with:
           go-version: stable

.github/workflows/mcp-diff.yml

@@ -19,6 +19,14 @@ jobs:
         with:
           fetch-depth: 0
 
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+
+      - name: Build UI
+        run: script/build-ui
+
       - name: Run MCP Server Diff
         uses: SamMorrowDrums/mcp-server-diff@v2.3.5
         with:

.gitignore

@@ -23,3 +23,12 @@ e2e.test
 
 .history
 conformance-report/
+
+# UI build artifacts
+ui/dist/
+ui/node_modules/
+
+# Embedded UI assets (built from ui/)
+pkg/github/ui_dist/*
+!pkg/github/ui_dist/.gitkeep
+!pkg/github/ui_dist/.placeholder.html

Dockerfile

@@ -1,3 +1,12 @@
+FROM node:20-alpine AS ui-build
+WORKDIR /app
+COPY ui/package*.json ./ui/
+RUN cd ui && npm ci
+COPY ui/ ./ui/
+# Create output directory and build - vite outputs directly to pkg/github/ui_dist/
+RUN mkdir -p ./pkg/github/ui_dist && \
+    cd ui && npm run build
+
 FROM golang:1.25.6-alpine AS build
 ARG VERSION="dev"
 
@@ -8,11 +17,15 @@ WORKDIR /build
 RUN --mount=type=cache,target=/var/cache/apk \
     apk add git
 
+# Copy source code (including ui_dist placeholder)
+COPY . .
+
+# Copy built UI assets over the placeholder
+COPY --from=ui-build /app/pkg/github/ui_dist/* ./pkg/github/ui_dist/
+
 # Build the server
-# go build automatically download required module dependencies to /go/pkg/mod
 RUN --mount=type=cache,target=/go/pkg/mod \
     --mount=type=cache,target=/root/.cache/go-build \
-    --mount=type=bind,target=. \
     CGO_ENABLED=0 go build -ldflags="-s -w -X main.version=${VERSION} -X main.commit=$(git rev-parse HEAD) -X main.date=$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
     -o /bin/github-mcp-server ./cmd/github-mcp-server
 

README.md

@@ -843,6 +843,11 @@ The following sets of tools are available:
   - `title`: Issue title (string, optional)
   - `type`: Type of this issue. Only use if the repository has issue types configured. Use list_issue_types tool to get valid type values for the organization. If the repository doesn't support issue types, omit this parameter. (string, optional)
 
+- **list_assignees** - List assignable users
+  - **Required OAuth Scopes**: `repo`
+  - `owner`: Repository owner (string, required)
+  - `repo`: Repository name (string, required)
+
 - **list_issue_types** - List available issue types
   - **Required OAuth Scopes**: `read:org`
   - **Accepted OAuth Scopes**: `admin:org`, `read:org`, `write:org`
@@ -860,6 +865,12 @@ The following sets of tools are available:
   - `since`: Filter by date (ISO 8601 timestamp) (string, optional)
   - `state`: Filter by state, by default both open and closed issues are returned when not provided (string, optional)
 
+- **list_milestones** - List milestones
+  - **Required OAuth Scopes**: `repo`
+  - `owner`: Repository owner (string, required)
+  - `repo`: Repository name (string, required)
+  - `state`: Filter by state (open, closed, all). Default: open (string, optional)
+
 - **search_issues** - Search issues
   - **Required OAuth Scopes**: `repo`
   - `order`: Sort order (string, optional)
@@ -1035,14 +1046,14 @@ The following sets of tools are available:
 
 - **create_pull_request** - Open new pull request
   - **Required OAuth Scopes**: `repo`
-  - `base`: Branch to merge into (string, required)
+  - `base`: Branch to merge into (string, optional)
   - `body`: PR description (string, optional)
   - `draft`: Create as draft PR (boolean, optional)
-  - `head`: Branch containing changes (string, required)
+  - `head`: Branch containing changes (string, optional)
   - `maintainer_can_modify`: Allow maintainer edits (boolean, optional)
   - `owner`: Repository owner (string, required)
   - `repo`: Repository name (string, required)
-  - `title`: PR title (string, required)
+  - `title`: PR title (string, optional)
 
 - **list_pull_requests** - List pull requests
   - **Required OAuth Scopes**: `repo`

internal/ghmcp/server.go

@@ -181,6 +181,7 @@ func NewMCPServer(cfg MCPServerConfig) (*mcp.Server, error) {
 		WithToolsets(enabledToolsets).
 		WithTools(cfg.EnabledTools).
 		WithFeatureChecker(featureChecker).
+		WithInsidersMode(cfg.InsidersMode).
 		WithServerInstructions()
 
 	// Apply token scope filtering if scopes are known (for PAT filtering)
@@ -250,6 +251,11 @@ func NewMCPServer(cfg MCPServerConfig) (*mcp.Server, error) {
 	// enable toolsets or tools explicitly that do need registration).
 	inventory.RegisterAll(context.Background(), ghServer, deps)
 
+	// Register MCP App UI resources (static resources for tool UI) - insiders only
+	if cfg.InsidersMode {
+		github.RegisterUIResources(ghServer)
+	}
+
 	// Register dynamic toolset management tools (enable/disable) - these are separate
 	// meta-tools that control the inventory, not part of the inventory itself
 	if cfg.DynamicToolsets {

pkg/github/__toolsnaps__/create_pull_request.snap

@@ -1,4 +1,13 @@
 {
+  "_meta": {
+    "ui": {
+      "resourceUri": "ui://github-mcp-server/pr-write",
+      "visibility": [
+        "model",
+        "app"
+      ]
+    }
+  },
   "annotations": {
     "title": "Open new pull request"
   },
@@ -40,10 +49,7 @@
     },
     "required": [
       "owner",
-      "repo",
-      "title",
-      "head",
-      "base"
+      "repo"
     ],
     "type": "object"
   },

pkg/github/__toolsnaps__/get_me.snap

@@ -1,4 +1,9 @@
 {
+  "_meta": {
+    "ui": {
+      "resourceUri": "ui://github-mcp-server/get-me"
+    }
+  },
   "annotations": {
     "readOnlyHint": true,
     "title": "Get my user profile"

pkg/github/__toolsnaps__/issue_write.snap

@@ -1,4 +1,13 @@
 {
+  "_meta": {
+    "ui": {
+      "resourceUri": "ui://github-mcp-server/issue-write",
+      "visibility": [
+        "model",
+        "app"
+      ]
+    }
+  },
   "annotations": {
     "title": "Create or update issue."
   },

pkg/github/__toolsnaps__/list_assignees.snap

@@ -0,0 +1,25 @@
+{
+  "annotations": {
+    "readOnlyHint": true,
+    "title": "List assignable users"
+  },
+  "description": "List available assignees for a repository. Returns users who can be assigned to issues.",
+  "inputSchema": {
+    "properties": {
+      "owner": {
+        "description": "Repository owner",
+        "type": "string"
+      },
+      "repo": {
+        "description": "Repository name",
+        "type": "string"
+      }
+    },
+    "required": [
+      "owner",
+      "repo"
+    ],
+    "type": "object"
+  },
+  "name": "list_assignees"
+}

pkg/github/__toolsnaps__/list_milestones.snap

@@ -0,0 +1,34 @@
+{
+  "annotations": {
+    "readOnlyHint": true,
+    "title": "List milestones"
+  },
+  "description": "List milestones for a repository.",
+  "inputSchema": {
+    "properties": {
+      "owner": {
+        "description": "Repository owner",
+        "type": "string"
+      },
+      "repo": {
+        "description": "Repository name",
+        "type": "string"
+      },
+      "state": {
+        "description": "Filter by state (open, closed, all). Default: open",
+        "enum": [
+          "open",
+          "closed",
+          "all"
+        ],
+        "type": "string"
+      }
+    },
+    "required": [
+      "owner",
+      "repo"
+    ],
+    "type": "object"
+  },
+  "name": "list_milestones"
+}

pkg/github/context_tools.go

@@ -15,6 +15,9 @@ import (
 	"github.com/shurcooL/githubv4"
 )
 
+// GetMeUIResourceURI is the URI for the get_me tool's MCP App UI resource.
+const GetMeUIResourceURI = "ui://github-mcp-server/get-me"
+
 // UserDetails contains additional fields about a GitHub user not already
 // present in MinimalUser. Used by get_me context tool but omitted from search_users.
 type UserDetails struct {
@@ -51,6 +54,11 @@ func GetMe(t translations.TranslationHelperFunc) inventory.ServerTool {
 			// Use json.RawMessage to ensure "properties" is included even when empty.
 			// OpenAI strict mode requires the properties field to be present.
 			InputSchema: json.RawMessage(`{"type":"object","properties":{}}`),
+			Meta: mcp.Meta{
+				"ui": map[string]any{
+					"resourceUri": GetMeUIResourceURI,
+				},
+			},
 		},
 		nil,
 		func(ctx context.Context, deps ToolDependencies, _ *mcp.CallToolRequest, _ map[string]any) (*mcp.CallToolResult, any, error) {