add projectRoot flag so the binary can be re-used and used outside of the project root directory

Author: tmaiaroto

AGENT_DOCS/PRD/PRD.md

@@ -24,6 +24,28 @@ As a developer using an AI coding agent, I want to:
 
 The MCP server will expose the following **seven** tools to the AI agent. The agent will use the tool descriptions to decide which tool to call based on the user's request.
 
+### Deployment Configuration
+
+**Custom Project Root Support**: The server supports a `--projectRoot` command-line argument that allows users to specify where project files (sgconfig.yml, rules/, etc.) should be created, regardless of where the binary is located. This solves cross-platform deployment issues where the binary may be installed in a system location separate from project directories.
+
+**Usage**:
+```bash
+# Command line
+context-sherpa --projectRoot="/path/to/project"
+
+# MCP configuration
+{
+  "mcpServers": {
+    "context-sherpa": {
+      "command": "context-sherpa",
+      "args": ["--projectRoot", "/path/to/project"]
+    }
+  }
+}
+```
+
+This ensures consistent file locations across different installation scenarios and platforms.
+
 ### Tool 1: `initialize_ast_grep`
 
 -   **Description**: "Initializes an ast-grep project if one is not already present. It creates the `sgconfig.yml` file and a `rules` directory. This tool should be suggested if another tool fails due to a missing configuration file."

README.md

@@ -22,15 +22,44 @@ Context Sherpa is delivered as a single, self-contained binary for easy integrat
 
 1.  Navigate to the [releases page](https://github.com/hackafterdark/context-sherpa/releases/latest) of the GitHub repository.
 2.  Download the binary that matches your operating system and architecture:
-    - `context-sherpa-linux-amd64` (Linux)
-    - `context-sherpa-darwin-amd64` or `context-sherpa-darwin-arm64` (macOS)
-    - `context-sherpa-windows-amd64.exe` or `context-sherpa-windows-arm64.exe` (Windows)
+     - `context-sherpa-linux-amd64` (Linux)
+     - `context-sherpa-darwin-amd64` or `context-sherpa-darwin-arm64` (macOS)
+     - `context-sherpa-windows-amd64.exe` or `context-sherpa-windows-arm64.exe` (Windows)
 3.  Configure your AI coding tool (Roo Code, Cline, Cursor, etc.) to use Context Sherpa as an MCP server.
 
 ### Option 2: Build from Source
 
 You can also build from source, though you'll need to ensure the `ast-grep` binary is available (see Contributing section below).
 
+```bash
+go build -o context-sherpa ./cmd/server
+```
+
+## Configuration
+
+### Custom Project Root (Optional)
+
+If your MCP server binary is installed in a different location than your project directory, you can specify a custom project root:
+
+**Command Line:**
+```bash
+context-sherpa --projectRoot="/path/to/your/project"
+```
+
+**MCP Configuration:**
+```json
+{
+  "mcpServers": {
+    "context-sherpa": {
+      "command": "context-sherpa",
+      "args": ["--projectRoot", "/path/to/your/project"]
+    }
+  }
+}
+```
+
+This ensures that `sgconfig.yml`, `rules/`, and other project files are created in your actual project directory rather than where the binary is located.
+
 ## Features
 
 - **Dynamic Rule Management**: Create, update, and remove linting rules on the fly based on natural language feedback.

cmd/server/main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	_ "embed"
+	"flag"
 
 	"github.com/hackafterdark/context-sherpa/internal/mcp"
 )
@@ -10,7 +11,10 @@ import (
 var astGrepBinary []byte
 
 func main() {
-	mcp.Start(astGrepBinary)
+	projectRoot := flag.String("projectRoot", "", "Project root directory (defaults to current working directory)")
+	flag.Parse()
+
+	mcp.Start(astGrepBinary, *projectRoot)
 }
 
 // GetAstGrepBinary returns the embedded ast-grep binary for testing

internal/mcp/server.go

@@ -58,13 +58,19 @@ var (
 
 var communityRulesRepo = "https://raw.githubusercontent.com/hackafterdark/context-sherpa-community-rules/main/index.json"
 
+// projectRootOverride stores the custom project root directory when specified via command-line argument
+var projectRootOverride string
+
 // getCommunityRulesRepoURL returns the community rules repository URL (can be overridden in tests)
 func getCommunityRulesRepoURL() string {
 	return communityRulesRepo
 }
 
 // Start initializes and starts the MCP server.
-func Start(sgBinary []byte) {
+func Start(sgBinary []byte, projectRoot string) {
+	if projectRoot != "" {
+		projectRootOverride = projectRoot
+	}
 	sgBinaryData = sgBinary
 
 	// Create a new MCP server
@@ -551,13 +557,22 @@ func addOrUpdateRuleHandler(ctx context.Context, req mcp.CallToolRequest) (*mcp.
 // findProjectRoot finds the project root by searching for sgconfig.yml
 // in the current and parent directories.
 func findProjectRoot() (string, error) {
-	dir, err := os.Getwd()
-	if err != nil {
-		return "", fmt.Errorf("could not get current directory: %v", err)
+	var dir string
+	var err error
+
+	if projectRootOverride != "" {
+		// Use the specified project root as starting point
+		dir = projectRootOverride
+	} else {
+		// Fall back to current behavior
+		dir, err = os.Getwd()
+		if err != nil {
+			return "", fmt.Errorf("could not get current directory: %v", err)
+		}
 	}
 
 	for {
-		configPath := dir + "/sgconfig.yml"
+		configPath := filepath.Join(dir, "sgconfig.yml")
 		if _, err := os.Stat(configPath); err == nil {
 			return dir, nil
 		}
@@ -594,13 +609,22 @@ func extractSgBinary(sgBinary []byte) (string, error) {
 // getRuleDir determines the directory where rules should be stored by searching
 // for sgconfig.yml in the current and parent directories.
 func getRuleDir() (string, error) {
-	dir, err := os.Getwd()
-	if err != nil {
-		return "", fmt.Errorf("could not get current directory: %v", err)
+	var dir string
+	var err error
+
+	if projectRootOverride != "" {
+		// Use the specified project root as starting point
+		dir = projectRootOverride
+	} else {
+		// Fall back to current behavior
+		dir, err = os.Getwd()
+		if err != nil {
+			return "", fmt.Errorf("could not get current directory: %v", err)
+		}
 	}
 
 	for {
-		configPath := dir + "/sgconfig.yml"
+		configPath := filepath.Join(dir, "sgconfig.yml")
 		if _, err := os.Stat(configPath); err == nil {
 			// Read and parse sgconfig.yml
 			data, err := os.ReadFile(configPath)
@@ -617,7 +641,7 @@ func getRuleDir() (string, error) {
 				return "", fmt.Errorf("ruleDirs not specified in sgconfig.yml")
 			}
 			// Return the first rule directory, relative to the config file's location
-			return dir + "/" + strings.TrimSpace(config.RuleDirs[0]), nil
+			return filepath.Join(dir, strings.TrimSpace(config.RuleDirs[0])), nil
 		}
 
 		// Move to parent directory
@@ -659,10 +683,17 @@ func removeRuleHandler(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallT
 }
 
 func initializeAstGrepHandler(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
-	// Get the current working directory as the project root
-	projectRoot, err := os.Getwd()
-	if err != nil {
-		return mcp.NewToolResultError(fmt.Sprintf("Error getting current directory: %v", err)), nil
+	// Determine the project root to use
+	var projectRoot string
+	var err error
+
+	if projectRootOverride != "" {
+		projectRoot = projectRootOverride
+	} else {
+		projectRoot, err = os.Getwd()
+		if err != nil {
+			return mcp.NewToolResultError(fmt.Sprintf("Error getting current directory: %v", err)), nil
+		}
 	}
 
 	// Create the rules directory if it doesn't exist
@@ -675,7 +706,7 @@ func initializeAstGrepHandler(ctx context.Context, req mcp.CallToolRequest) (*mc
 	sgconfigPath := filepath.Join(projectRoot, "sgconfig.yml")
 	sgconfigContent := `ruleDirs:
   - rules
-`
+ `
 	if err := os.WriteFile(sgconfigPath, []byte(sgconfigContent), 0644); err != nil {
 		return mcp.NewToolResultError(fmt.Sprintf("Error creating sgconfig.yml: %v", err)), nil
 	}