Add .plugin packaging (Cowork/Claude Code plugin variant)

plugin/ holds the plugin manifest, .mcp.json (CLAUDE_PLUGIN_ROOT paths), and
README; scripts/build-plugin.sh syncs the core client, esbuild-bundles the
server into a single ESM file (the plugin uploader rejects zip entries
containing "@", so no node_modules), and zips it as ms-todo.plugin. Same
server, two install formats (.mcpb + .plugin). Mirrors claude-msplanner.

Verified: the bundled server registers all 17 tools over stdio as ms-todo
v1.0.1.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

.gitignore

@@ -9,3 +9,6 @@
 
 # Node
 node_modules/
+
+# Built plugin bundle (source lives in plugin/; artifact goes on releases)
+*.plugin

README.md

@@ -24,6 +24,7 @@ Two ways to use it, sharing one core Graph client (`graph.mjs`):
 |---|---|---|
 | **Skill** | Claude Code on your own machine | `.claude/skills/ms-todo/` |
 | **Desktop extension (`.mcpb`)** | Claude Desktop, distributed org-wide | `mcp-extension/` |
+| **Plugin (`.plugin`)** | Claude Cowork / Claude Code plugin picker | `plugin/` (same server, bundled by `scripts/build-plugin.sh`) |
 
 ## Repo layout
 
@@ -38,16 +39,23 @@ Two ways to use it, sharing one core Graph client (`graph.mjs`):
 │   └── references/
 │       ├── setup.md                     # Entra app registration walkthrough (public client + loopback redirect)
 │       └── graph-api.md                 # todoTask field formats + OData query reference
-└── mcp-extension/                       # Claude Desktop extension (imports the same graph.mjs)
-    ├── manifest.json                    # .mcpb manifest (baked client/tenant id, user_config)
-    ├── server/index.mjs                 # MCP server (stdio) exposing todo_* tools
-    ├── scripts/sync-core.mjs            # copies the canonical graph.mjs into the bundle
-    └── README.md                        # build + install + admin setup
+├── mcp-extension/                       # Claude Desktop extension (imports the same graph.mjs)
+│   ├── manifest.json                    # .mcpb manifest (baked client/tenant id, user_config)
+│   ├── server/index.mjs                 # MCP server (stdio) exposing todo_* tools
+│   ├── scripts/sync-core.mjs            # copies the canonical graph.mjs into the bundle
+│   └── README.md                        # build + install + admin setup
+├── plugin/                              # .plugin (Cowork/Claude Code) packaging metadata
+│   ├── .claude-plugin/plugin.json       # plugin manifest
+│   └── .mcp.json                        # server launch config (CLAUDE_PLUGIN_ROOT paths)
+└── scripts/build-plugin.sh              # stages plugin/ + esbuild-bundled server -> ms-todo.plugin
 ```
 
 For Claude Desktop, build and distribute the extension — see
 [`mcp-extension/README.md`](mcp-extension/README.md). (Claude Desktop can't run
 Claude Code skills; it loads MCP servers, so the `.mcpb` is the right vehicle.)
+For Claude Cowork / Claude Code, run `./scripts/build-plugin.sh` and upload the
+resulting `ms-todo.plugin` in the plugin picker (that dialog only accepts
+`.zip`/`.plugin` — a `.mcpb` upload is rejected).
 
 ## Prerequisites (one-time)
 

plugin/.claude-plugin/plugin.json

@@ -0,0 +1,10 @@
+{
+  "name": "ms-todo",
+  "version": "1.0.1",
+  "description": "Microsoft To Do connector — read and write your task lists, tasks, and checklist items via Microsoft Graph. Sign in once with todo_login.",
+  "author": {
+    "name": "PESCO Inc."
+  },
+  "license": "MIT",
+  "keywords": ["microsoft", "to do", "todo", "tasks", "graph", "productivity"]
+}

plugin/.mcp.json

@@ -0,0 +1,12 @@
+{
+  "mcpServers": {
+    "ms-todo": {
+      "command": "node",
+      "args": ["${CLAUDE_PLUGIN_ROOT}/server/index.mjs"],
+      "env": {
+        "TODO_CLIENT_ID": "9af4a8a3-5290-4089-9058-a29dcce63c4f",
+        "TODO_TENANT_ID": "94c6c62d-8fe7-416f-8fef-7d8620b95819"
+      }
+    }
+  }
+}

plugin/README.md

@@ -0,0 +1,36 @@
+# Microsoft To Do plugin
+
+Connects Claude to Microsoft To Do via the Microsoft Graph API. This is the
+plugin (`.plugin`) packaging of the same MCP stdio server shipped as the
+`ms-todo.mcpb` Claude Desktop extension — one codebase, two install formats.
+
+## Install
+
+Upload `ms-todo.plugin` in the plugin picker. Then ask Claude to run
+`todo_login` once — a browser window opens for Microsoft sign-in. The refresh
+token is cached at `~/.ms-todo/token-cache.json` (shared with the
+Desktop-extension install, so you only ever sign in once per machine).
+
+## Requirements
+
+- Node.js >= 18 on PATH (the server is a Node stdio process).
+- A Microsoft work account in the PESCO tenant. Auth is delegated
+  (auth-code + PKCE); scopes: Tasks.ReadWrite, User.Read.
+
+## Configuration
+
+Environment is baked into `.mcp.json` (client + tenant id). Optional overrides:
+
+| Variable           | Purpose                                                  |
+| ------------------ | -------------------------------------------------------- |
+| `TODO_TOKEN_CACHE` | Alternate token cache path                               |
+| `TODO_TIMEZONE`    | Zone for due/start/reminder dates (default UTC)          |
+| `TODO_READONLY`    | "true" registers only the viewing tools                  |
+
+## Tools
+
+17 tools: `todo_login/logout/test`, list CRUD (`todo_list_lists/create_list/
+update_list/delete_list`), task CRUD (`todo_list_tasks/get_task/create_task/
+update_task/complete_task/delete_task`), checklist items (`todo_list_checklist/
+add_checklist_item/check_checklist_item/delete_checklist_item`).
+See the repository README for the full list.

scripts/build-plugin.sh

@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# Build ms-todo.plugin (the Cowork/Claude Code plugin bundle).
+#
+# The plugin uploader rejects zip entries containing "@" (npm scope directories
+# like node_modules/@modelcontextprotocol), so we don't ship node_modules at
+# all: esbuild bundles the server and its dependencies into a single ESM file.
+# Output: ./ms-todo.plugin with contents at the archive root, as the plugin
+# format requires.
+set -euo pipefail
+cd "$(dirname "$0")/.."
+
+STAGE="$(mktemp -d)"
+trap 'rm -rf "$STAGE"' EXIT
+
+cp -R plugin/.claude-plugin "$STAGE/.claude-plugin"
+cp plugin/.mcp.json plugin/README.md "$STAGE/"
+mkdir -p "$STAGE/server"
+
+# Sync the canonical core client into the extension, then install prod deps.
+(cd mcp-extension && npm run sync --silent && npm ci --omit=dev --silent)
+# The require() shim is for CJS dependencies inside the ESM bundle.
+npx -y esbuild mcp-extension/server/index.mjs \
+  --bundle --platform=node --format=esm --target=node18 \
+  --banner:js="import { createRequire } from 'node:module'; const require = createRequire(import.meta.url);" \
+  --outfile="$STAGE/server/index.mjs" --log-level=warning
+
+rm -f ms-todo.plugin
+(cd "$STAGE" && zip -qr - . -x "*.DS_Store") > ms-todo.plugin
+echo "Built $(pwd)/ms-todo.plugin ($(du -h ms-todo.plugin | cut -f1 | tr -d ' '))"