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+# XER MCP Server
+
+An MCP (Model Context Protocol) server for parsing Primavera P6 XER files and exposing schedule data to AI assistants.
+
+## Features
+
+- Parse Primavera P6 XER export files
+- Query activities, relationships, milestones, and critical path
+- Pagination support with configurable limits
+- Multi-project file support
+- In-memory SQLite database for fast queries
+
+## Installation
+
+Requires Python 3.12+
+
+```bash
+# Clone the repository
+git clone https://git.prettyhefty.com/Bill/xer-mcp.git
+cd xer-mcp
+
+# Install with uv
+uv sync
+
+# Or install with pip
+pip install -e .
+```
+
+## Configuration
+
+### Claude Desktop
+
+Add to your Claude Desktop configuration (`~/.config/claude/claude_desktop_config.json` on Linux, `~/Library/Application Support/Claude/claude_desktop_config.json` on macOS):
+
+```json
+{
+  "mcpServers": {
+    "xer-mcp": {
+      "command": "uv",
+      "args": ["run", "--directory", "/path/to/xer-mcp", "python", "-m", "xer_mcp"]
+    }
+  }
+}
+```
+
+### Other MCP Clients
+
+Run the server directly:
+
+```bash
+uv run python -m xer_mcp
+```
+
+The server communicates via stdio using the MCP protocol.
+
+## Available Tools
+
+### load_xer
+
+Load a Primavera P6 XER file for querying.
+
+**Parameters:**
+- `file_path` (required): Absolute path to the XER file
+- `project_id` (optional): Project ID to select (required for multi-project files)
+
+**Example:**
+```json
+{
+  "file_path": "/path/to/schedule.xer"
+}
+```
+
+### list_activities
+
+List activities with optional filtering and pagination.
+
+**Parameters:**
+- `start_date` (optional): Filter activities starting on or after (YYYY-MM-DD)
+- `end_date` (optional): Filter activities ending on or before (YYYY-MM-DD)
+- `wbs_id` (optional): Filter by WBS element ID
+- `activity_type` (optional): Filter by type (TT_Task, TT_Mile, TT_LOE, TT_WBS, TT_Rsrc)
+- `limit` (optional): Maximum results (default: 100, max: 1000)
+- `offset` (optional): Number of results to skip (default: 0)
+
+**Returns:** List of activities with pagination metadata
+
+### get_activity
+
+Get detailed information for a specific activity.
+
+**Parameters:**
+- `activity_id` (required): The task_id of the activity
+
+**Returns:** Activity details including WBS name and relationship counts
+
+### list_relationships
+
+List all activity relationships (dependencies) with pagination.
+
+**Parameters:**
+- `limit` (optional): Maximum results (default: 100, max: 1000)
+- `offset` (optional): Number of results to skip (default: 0)
+
+**Returns:** List of relationships with predecessor/successor info
+
+### get_predecessors
+
+Get predecessor activities for a given activity.
+
+**Parameters:**
+- `activity_id` (required): The task_id of the activity
+
+**Returns:** List of predecessor activities with relationship type and lag
+
+### get_successors
+
+Get successor activities for a given activity.
+
+**Parameters:**
+- `activity_id` (required): The task_id of the activity
+
+**Returns:** List of successor activities with relationship type and lag
+
+### get_project_summary
+
+Get a summary of the loaded project.
+
+**Parameters:** None
+
+**Returns:**
+- `project_name`: Name of the project
+- `plan_start_date`: Planned start date
+- `plan_end_date`: Planned end date
+- `activity_count`: Total number of activities
+- `milestone_count`: Number of milestones
+- `critical_activity_count`: Number of activities on critical path
+
+### list_milestones
+
+List all milestone activities in the project.
+
+**Parameters:** None
+
+**Returns:** List of milestone activities with dates and status
+
+### get_critical_path
+
+Get all activities on the critical path.
+
+**Parameters:** None
+
+**Returns:** List of critical path activities ordered by start date
+
+## Usage Example
+
+1. First, load an XER file:
+   ```
+   Use the load_xer tool with file_path: "/path/to/my-schedule.xer"
+   ```
+
+2. Get a project overview:
+   ```
+   Use the get_project_summary tool
+   ```
+
+3. List upcoming milestones:
+   ```
+   Use the list_milestones tool
+   ```
+
+4. View critical path:
+   ```
+   Use the get_critical_path tool
+   ```
+
+5. Query specific activities:
+   ```
+   Use list_activities with start_date: "2026-01-01" and end_date: "2026-03-31"
+   ```
+
+## Error Handling
+
+All query tools return a `NO_FILE_LOADED` error if called before loading an XER file:
+
+```json
+{
+  "error": {
+    "code": "NO_FILE_LOADED",
+    "message": "No XER file is loaded. Use the load_xer tool first."
+  }
+}
+```
+
+## Relationship Types
+
+The server supports all P6 relationship types:
+- **FS** (Finish-to-Start): Successor starts after predecessor finishes
+- **SS** (Start-to-Start): Successor starts when predecessor starts
+- **FF** (Finish-to-Finish): Successor finishes when predecessor finishes
+- **SF** (Start-to-Finish): Successor finishes when predecessor starts
+
+## Development
+
+```bash
+# Run tests
+uv run pytest
+
+# Run with coverage
+uv run pytest --cov=xer_mcp
+
+# Lint
+uv run ruff check src/ tests/
+
+# Format
+uv run ruff format src/ tests/
+```
+
+## License
+
+MIT