diff --git a/SPEC.md b/SPEC.md
index 5383be1..974ca4f 100644
--- a/SPEC.md
+++ b/SPEC.md
@@ -4,16 +4,17 @@ This is the spec for the Ghost Blog platform MCP server.
 
 ## Goal
 
-- The main goal is to implement the MCP tools for all https://docs.ghost.org/content-api REST actions
-- Provide a comprehensive MCP server that allows Claude to interact with Ghost blog content
+- The main goal is to implement the MCP tools for all Ghost REST API actions (both Content and Admin APIs)
+- Provide a comprehensive MCP server that allows Claude to interact with Ghost blog content for both reading and writing
 - Support all major Ghost Content API endpoints for reading published content
+- Support all major Ghost Admin API endpoints for creating, updating, and deleting content
 
 ## Requirements
 
 ### Infrastructure
-- Deploy a local Ghost instance using `docker compose` and figure out a way to create an API key
-- Set up proper authentication using Ghost Content API keys
-- Configure the MCP server to connect to the Ghost instance
+- Deploy a local Ghost instance using `docker compose` and figure out a way to create API keys
+- Set up proper authentication using both Ghost Content API keys (read-only) and Admin API keys (read/write)
+- Configure the MCP server to connect to the Ghost instance with appropriate permissions
 
 ### Development
 - Implement MCP server using Node.js/TypeScript
@@ -55,6 +56,75 @@ The Ghost Content API provides read-only access to published content. All endpoi
 ### Settings
 - `GET /settings/` - Get public settings
 
+## Ghost Admin API Endpoints
+
+The Ghost Admin API provides full read/write access to all Ghost content. All endpoints require Admin API authentication.
+
+### Posts (Admin)
+- `GET /admin/posts/` - Browse posts (including drafts)
+- `GET /admin/posts/{id}/` - Read a specific post
+- `POST /admin/posts/` - Create a new post
+- `PUT /admin/posts/{id}/` - Update an existing post
+- `POST /admin/posts/{id}/copy/` - Copy a post
+- `DELETE /admin/posts/{id}/` - Delete a post
+
+### Pages (Admin)
+- `GET /admin/pages/` - Browse pages (including drafts)
+- `GET /admin/pages/{id}/` - Read a specific page
+- `POST /admin/pages/` - Create a new page
+- `PUT /admin/pages/{id}/` - Update an existing page
+- `POST /admin/pages/{id}/copy/` - Copy a page
+- `DELETE /admin/pages/{id}/` - Delete a page
+
+### Tags (Admin)
+- `GET /admin/tags/` - Browse all tags
+- `GET /admin/tags/{id}/` - Read a specific tag
+- `POST /admin/tags/` - Create a new tag
+- `PUT /admin/tags/{id}/` - Update an existing tag
+- `DELETE /admin/tags/{id}/` - Delete a tag
+
+### Tiers (Admin)
+- `GET /admin/tiers/` - Browse membership tiers
+- `GET /admin/tiers/{id}/` - Read a specific tier
+- `POST /admin/tiers/` - Create a new tier
+- `PUT /admin/tiers/{id}/` - Update an existing tier
+
+### Members (Admin)
+- `GET /admin/members/` - Browse members
+- `GET /admin/members/{id}/` - Read a specific member
+- `POST /admin/members/` - Create a new member
+- `PUT /admin/members/{id}/` - Update an existing member
+
+### Users (Admin)
+- `GET /admin/users/` - Browse users
+- `GET /admin/users/{id}/` - Read a specific user
+
+### Media (Admin)
+- `POST /admin/images/upload/` - Upload images
+- `POST /admin/media/upload/` - Upload media files
+
+### Themes (Admin)
+- `POST /admin/themes/upload/` - Upload theme
+- `PUT /admin/themes/{name}/activate/` - Activate theme
+
+### Webhooks (Admin)
+- `GET /admin/webhooks/` - Browse webhooks
+- `POST /admin/webhooks/` - Create webhook
+- `PUT /admin/webhooks/{id}/` - Update webhook
+- `DELETE /admin/webhooks/{id}/` - Delete webhook
+
+### Newsletters (Admin)
+- `GET /admin/newsletters/` - Browse newsletters
+- `GET /admin/newsletters/{id}/` - Read newsletter
+- `POST /admin/newsletters/` - Create newsletter
+- `PUT /admin/newsletters/{id}/` - Update newsletter
+
+### Offers (Admin)
+- `GET /admin/offers/` - Browse offers
+- `GET /admin/offers/{id}/` - Read offer
+- `POST /admin/offers/` - Create offer
+- `PUT /admin/offers/{id}/` - Update offer
+
 ## API Response Format
 
 All Ghost Content API responses follow this structure:
@@ -139,6 +209,141 @@ The following MCP tools should be implemented to provide comprehensive access to
   - Parameters: None
   - Returns: Settings object
 
+## Admin API MCP Tools
+
+The following MCP tools provide full read/write access to Ghost content via the Admin API:
+
+### Posts Admin Tools
+- **`ghost_admin_list_posts`** - Browse all posts (including drafts)
+  - Parameters: `limit?` (number), `page?` (number), `filter?` (string), `include?` (string), `fields?` (string)
+  - Returns: Array of post objects with pagination metadata
+
+- **`ghost_admin_get_post`** - Read a specific post by ID
+  - Parameters: `id` (required string), `include?` (string), `fields?` (string)
+  - Returns: Single post object
+
+- **`ghost_admin_create_post`** - Create a new post
+  - Parameters: `title` (required string), `html?` (string), `mobiledoc?` (string), `lexical?` (string), `status?` (string), `slug?` (string), `excerpt?` (string), `meta_title?` (string), `meta_description?` (string), `tags?` (array), `authors?` (array), `featured?` (boolean), `published_at?` (string)
+  - Returns: Created post object
+
+- **`ghost_admin_update_post`** - Update an existing post
+  - Parameters: `id` (required string), `title?` (string), `html?` (string), `mobiledoc?` (string), `lexical?` (string), `status?` (string), `slug?` (string), `excerpt?` (string), `meta_title?` (string), `meta_description?` (string), `tags?` (array), `authors?` (array), `featured?` (boolean), `published_at?` (string), `updated_at` (required string)
+  - Returns: Updated post object
+
+- **`ghost_admin_copy_post`** - Copy an existing post
+  - Parameters: `id` (required string)
+  - Returns: Copied post object
+
+- **`ghost_admin_delete_post`** - Delete a post
+  - Parameters: `id` (required string)
+  - Returns: Success confirmation
+
+### Pages Admin Tools
+- **`ghost_admin_list_pages`** - Browse all pages (including drafts)
+  - Parameters: `limit?` (number), `page?` (number), `filter?` (string), `include?` (string), `fields?` (string)
+  - Returns: Array of page objects with pagination metadata
+
+- **`ghost_admin_get_page`** - Read a specific page by ID
+  - Parameters: `id` (required string), `include?` (string), `fields?` (string)
+  - Returns: Single page object
+
+- **`ghost_admin_create_page`** - Create a new page
+  - Parameters: `title` (required string), `html?` (string), `mobiledoc?` (string), `lexical?` (string), `status?` (string), `slug?` (string), `excerpt?` (string), `meta_title?` (string), `meta_description?` (string), `tags?` (array), `authors?` (array), `featured?` (boolean), `published_at?` (string)
+  - Returns: Created page object
+
+- **`ghost_admin_update_page`** - Update an existing page
+  - Parameters: `id` (required string), `title?` (string), `html?` (string), `mobiledoc?` (string), `lexical?` (string), `status?` (string), `slug?` (string), `excerpt?` (string), `meta_title?` (string), `meta_description?` (string), `tags?` (array), `authors?` (array), `featured?` (boolean), `published_at?` (string), `updated_at` (required string)
+  - Returns: Updated page object
+
+- **`ghost_admin_copy_page`** - Copy an existing page
+  - Parameters: `id` (required string)
+  - Returns: Copied page object
+
+- **`ghost_admin_delete_page`** - Delete a page
+  - Parameters: `id` (required string)
+  - Returns: Success confirmation
+
+### Tags Admin Tools
+- **`ghost_admin_list_tags`** - Browse all tags
+  - Parameters: `limit?` (number), `page?` (number), `filter?` (string), `include?` (string), `fields?` (string)
+  - Returns: Array of tag objects with pagination metadata
+
+- **`ghost_admin_get_tag`** - Read a specific tag by ID
+  - Parameters: `id` (required string), `include?` (string), `fields?` (string)
+  - Returns: Single tag object
+
+- **`ghost_admin_create_tag`** - Create a new tag
+  - Parameters: `name` (required string), `slug?` (string), `description?` (string), `feature_image?` (string), `meta_title?` (string), `meta_description?` (string), `visibility?` (string)
+  - Returns: Created tag object
+
+- **`ghost_admin_update_tag`** - Update an existing tag
+  - Parameters: `id` (required string), `name?` (string), `slug?` (string), `description?` (string), `feature_image?` (string), `meta_title?` (string), `meta_description?` (string), `visibility?` (string), `updated_at` (required string)
+  - Returns: Updated tag object
+
+- **`ghost_admin_delete_tag`** - Delete a tag
+  - Parameters: `id` (required string)
+  - Returns: Success confirmation
+
+### Members Admin Tools
+- **`ghost_admin_list_members`** - Browse all members
+  - Parameters: `limit?` (number), `page?` (number), `filter?` (string), `include?` (string), `fields?` (string)
+  - Returns: Array of member objects with pagination metadata
+
+- **`ghost_admin_get_member`** - Read a specific member by ID
+  - Parameters: `id` (required string), `include?` (string), `fields?` (string)
+  - Returns: Single member object
+
+- **`ghost_admin_create_member`** - Create a new member
+  - Parameters: `email` (required string), `name?` (string), `note?` (string), `subscribed?` (boolean), `comped?` (boolean), `labels?` (array), `newsletters?` (array)
+  - Returns: Created member object
+
+- **`ghost_admin_update_member`** - Update an existing member
+  - Parameters: `id` (required string), `email?` (string), `name?` (string), `note?` (string), `subscribed?` (boolean), `comped?` (boolean), `labels?` (array), `newsletters?` (array), `updated_at` (required string)
+  - Returns: Updated member object
+
+### Media Admin Tools
+- **`ghost_admin_upload_image`** - Upload an image
+  - Parameters: `file` (required file/base64), `purpose?` (string), `ref?` (string)
+  - Returns: Uploaded image URL and metadata
+
+- **`ghost_admin_upload_media`** - Upload media file
+  - Parameters: `file` (required file/base64), `purpose?` (string), `ref?` (string)
+  - Returns: Uploaded media URL and metadata
+
+### Tiers Admin Tools
+- **`ghost_admin_list_tiers`** - Browse membership tiers
+  - Parameters: `limit?` (number), `page?` (number), `include?` (string), `fields?` (string)
+  - Returns: Array of tier objects
+
+- **`ghost_admin_get_tier`** - Read a specific tier by ID
+  - Parameters: `id` (required string), `include?` (string), `fields?` (string)
+  - Returns: Single tier object
+
+- **`ghost_admin_create_tier`** - Create a new membership tier
+  - Parameters: `name` (required string), `description?` (string), `monthly_price?` (number), `yearly_price?` (number), `currency?` (string), `trial_days?` (number), `visibility?` (string), `welcome_page_url?` (string), `benefits?` (array)
+  - Returns: Created tier object
+
+- **`ghost_admin_update_tier`** - Update an existing tier
+  - Parameters: `id` (required string), `name?` (string), `description?` (string), `monthly_price?` (number), `yearly_price?` (number), `currency?` (string), `trial_days?` (number), `visibility?` (string), `welcome_page_url?` (string), `benefits?` (array), `updated_at` (required string)
+  - Returns: Updated tier object
+
+### Webhooks Admin Tools
+- **`ghost_admin_list_webhooks`** - Browse webhooks
+  - Parameters: `limit?` (number), `page?` (number)
+  - Returns: Array of webhook objects
+
+- **`ghost_admin_create_webhook`** - Create a new webhook
+  - Parameters: `event` (required string), `target_url` (required string), `name?` (string), `secret?` (string), `api_version?` (string), `integration_id?` (string)
+  - Returns: Created webhook object
+
+- **`ghost_admin_update_webhook`** - Update an existing webhook
+  - Parameters: `id` (required string), `event?` (string), `target_url?` (string), `name?` (string), `secret?` (string), `api_version?` (string), `updated_at` (required string)
+  - Returns: Updated webhook object
+
+- **`ghost_admin_delete_webhook`** - Delete a webhook
+  - Parameters: `id` (required string)
+  - Returns: Success confirmation
+
 ### Common Parameters
 - `limit`: Number of resources to return (default: 15, max: 50)
 - `page`: Page number for pagination (default: 1)
@@ -189,8 +394,24 @@ volumes:
 1. Start the Ghost instance: `docker compose up -d`
 2. Visit `http://localhost:2368/ghost` to set up your admin account
 3. Navigate to Settings → Integrations → Custom Integrations
-4. Create a new integration to get your Content API key
-5. Save the Content API key for MCP server configuration
+4. Create a new custom integration which provides:
+   - **Content API Key**: For read-only access to published content
+   - **Admin API Key**: For full read/write access to all Ghost content
+5. Save both API keys for MCP server configuration
+
+### Authentication Types
+
+#### Content API Authentication
+- **Purpose**: Read-only access to published content
+- **Security**: Safe for browser/public environments
+- **Authentication**: Content API key passed as query parameter
+- **Scope**: Posts, pages, tags, authors, tiers, settings (published content only)
+
+#### Admin API Authentication
+- **Purpose**: Full read/write access to all Ghost content
+- **Security**: Must remain secret, server-side only
+- **Authentication**: Admin API key with JWT token generation
+- **Scope**: All Ghost resources including drafts, members, webhooks, media uploads
 
 ## Configuration
 
@@ -198,8 +419,10 @@ The MCP server should support configuration via:
 
 ### Environment Variables
 - `GHOST_URL`: Ghost instance URL (default: http://localhost:2368)
-- `GHOST_CONTENT_API_KEY`: Content API key (required)
+- `GHOST_CONTENT_API_KEY`: Content API key (required for read operations)
+- `GHOST_ADMIN_API_KEY`: Admin API key (required for write operations)
 - `GHOST_VERSION`: API version (default: v5.0)
+- `MCP_GHOST_MODE`: Operation mode - "readonly", "readwrite", or "auto" (default: "auto")
 
 ### Configuration File
 Alternative JSON configuration file:
@@ -208,11 +431,18 @@ Alternative JSON configuration file:
   "ghost": {
     "url": "http://localhost:2368",
     "contentApiKey": "your-content-api-key",
-    "version": "v5.0"
+    "adminApiKey": "your-admin-api-key",
+    "version": "v5.0",
+    "mode": "readwrite"
   }
 }
 ```
 
+### Operation Modes
+- **readonly**: Only Content API tools are available (requires Content API key)
+- **readwrite**: All tools available (requires both Content and Admin API keys)
+- **auto**: Automatically detects available keys and enables appropriate tools
+
 ## Implementation Details
 
 ### Project Structure
@@ -220,13 +450,25 @@ Alternative JSON configuration file:
 ghost-mcp/
 ├── src/
 │   ├── index.ts              # MCP server entry point
-│   ├── ghost-client.ts       # Ghost API client
+│   ├── ghost-client.ts       # Ghost API client (both Content and Admin)
+│   ├── auth/
+│   │   ├── content-auth.ts   # Content API authentication
+│   │   └── admin-auth.ts     # Admin API JWT authentication
 │   ├── tools/
-│   │   ├── posts.ts          # Post-related tools
-│   │   ├── pages.ts          # Page-related tools
-│   │   ├── tags.ts           # Tag-related tools
-│   │   ├── authors.ts        # Author-related tools
-│   │   └── settings.ts       # Settings and tiers tools
+│   │   ├── content/          # Content API tools (read-only)
+│   │   │   ├── posts.ts
+│   │   │   ├── pages.ts
+│   │   │   ├── tags.ts
+│   │   │   ├── authors.ts
+│   │   │   └── settings.ts
+│   │   └── admin/           # Admin API tools (read/write)
+│   │       ├── posts.ts
+│   │       ├── pages.ts
+│   │       ├── tags.ts
+│   │       ├── members.ts
+│   │       ├── media.ts
+│   │       ├── tiers.ts
+│   │       └── webhooks.ts
 │   ├── types/
 │   │   ├── ghost.ts          # Ghost API response types
 │   │   └── mcp.ts            # MCP-specific types
@@ -243,14 +485,18 @@ ghost-mcp/
 - **Node.js** (v18+) with **TypeScript**
 - **@modelcontextprotocol/sdk** for MCP implementation
 - **axios** or **fetch** for HTTP requests
+- **jsonwebtoken** for Admin API JWT authentication
 - **zod** for runtime type validation
 - **dotenv** for environment variable management
+- **multer** or equivalent for file upload handling
 
 ### Error Handling
 - Validate all input parameters using Zod schemas
 - Handle Ghost API errors gracefully with meaningful messages
 - Implement retry logic for transient network errors
 - Return proper MCP error responses with error codes
+- Handle authentication failures for both Content and Admin APIs
+- Graceful degradation when only one API key is available
 
 ### Testing Strategy
 - Unit tests for individual tools and utilities
@@ -268,17 +514,7 @@ ghost-mcp/
 
 Before proceeding with implementation, please clarify the following:
 
-### 1. API Scope
-- **Question**: Should this MCP server be read-only (Content API) or also include write operations (Admin API)?
-- **Impact**: Admin API would require different authentication and additional tools for creating/updating content
-- **Recommendation**: Start with read-only Content API for initial implementation
-
-### 2. Authentication Strategy
-- **Question**: Do you want to support both Content API keys and Admin API keys?
-- **Impact**: Different authentication methods have different capabilities and security considerations
-- **Recommendation**: Begin with Content API keys only
-
-### 3. Filtering and Pagination
+### 1. Filtering and Pagination
 - **Question**: Should all Ghost API filtering/pagination options be exposed as tool parameters?
 - **Impact**: More parameters provide flexibility but increase complexity
 - **Options**:
@@ -286,12 +522,12 @@ Before proceeding with implementation, please clarify the following:
   - Simplified parameter set (easier to use)
   - Progressive enhancement (start simple, add more later)
 
-### 4. Error Handling Strategy
+### 2. Error Handling Strategy
 - **Question**: Any specific error handling or retry logic requirements?
 - **Impact**: Affects reliability and user experience
 - **Considerations**: Network timeouts, rate limits, API downtime
 
-### 5. Configuration Management
+### 3. Configuration Management
 - **Question**: How should the Ghost instance URL and API keys be configured?
 - **Options**:
   - Environment variables only
@@ -299,7 +535,7 @@ Before proceeding with implementation, please clarify the following:
   - Both (with precedence order)
   - Runtime configuration via MCP parameters
 
-### 6. Additional Features
+### 4. Additional Features
 - **Question**: Are there any additional features beyond basic CRUD operations?
 - **Examples**:
   - Content search across posts/pages
@@ -307,7 +543,7 @@ Before proceeding with implementation, please clarify the following:
   - Content analytics/statistics
   - Webhook support for real-time updates
 
-### 7. Development Environment
+### 5. Development Environment
 - **Question**: Should the development setup include sample Ghost content for testing?
 - **Impact**: Makes testing and development easier but increases setup complexity