get_doctype_schema

Retrieve the complete schema for a Frappe DocType, including field definitions, validations, and linked DocTypes to understand document structure before creating or updating records.

Instructions

    Get the complete schema for a DocType including field definitions, validations, and linked DocTypes.
    
    Use this to understand the structure of a DocType before creating or updating documents.
    
    Args:
        doctype: DocType name

Input Schema

TableJSON Schema

Name	Required	Description	Default
`doctype`	Yes

Implementation Reference

src/tools/schema.py:39-93 (handler)

The handler function for the 'get_doctype_schema' tool. It retrieves the DocType schema from the Frappe API, formats the fields summary, and returns JSON. Includes error handling.

@mcp.tool()
async def get_doctype_schema(doctype: str) -> str:
    """
    Get the complete schema for a DocType including field definitions, validations, and linked DocTypes.
    
    Use this to understand the structure of a DocType before creating or updating documents.
    
    Args:
        doctype: DocType name
    """
    try:
        client = get_client()
        
        # Get DocType schema
        response = await client.get(f"api/resource/DocType/{doctype}")
        
        if "data" in response:
            schema_data = response["data"]
            
            # Format the response to highlight key information
            fields = schema_data.get("fields", [])
            field_summary = []
            
            for field in fields:
                field_info = {
                    "label": field.get("label"),
                    "fieldname": field.get("fieldname"),
                    "fieldtype": field.get("fieldtype"),
                    "reqd": field.get("reqd", 0) == 1,
                    "options": field.get("options"),
                    "default": field.get("default")
                }
                if field.get("description"):
                    field_info["description"] = field.get("description")
                field_summary.append(field_info)
            
            formatted_response = {
                "doctype": doctype,
                "module": schema_data.get("module"),
                "naming_rule": schema_data.get("autoname"),
                "is_submittable": schema_data.get("is_submittable", 0) == 1,
                "is_tree": schema_data.get("is_tree", 0) == 1,
                "track_changes": schema_data.get("track_changes", 0) == 1,
                "allow_rename": schema_data.get("allow_rename", 0) == 1,
                "fields": field_summary,
                "permissions": schema_data.get("permissions", [])
            }
            
            return json.dumps(formatted_response, indent=2)
        else:
            return json.dumps(response, indent=2)
            
    except Exception as error:
        return _format_error_response(error, "get_doctype_schema")

src/server.py:38-42 (registration)
Central registration point where schema.register_tools(mcp) is called to register all tools from the schema module, including 'get_doctype_schema'.
```
# Register all tool modules
helpers.register_tools(mcp)
documents.register_tools(mcp)
schema.register_tools(mcp)
reports.register_tools(mcp)
```

src/tools/schema.py:15-34 (helper)

Helper function used by get_doctype_schema to format and return error responses with authentication and API error handling.

def _format_error_response(error: Exception, operation: str) -> str:
    """Format error response with detailed information."""
    credentials_check = validate_api_credentials()
    
    # Check for missing credentials first
    if not credentials_check["valid"]:
        error_msg = f"Authentication failed: {credentials_check['message']}. "
        error_msg += "API key/secret is the only supported authentication method."
        return error_msg
    
    # Handle FrappeApiError
    if isinstance(error, FrappeApiError):
        error_msg = f"Frappe API error: {error}"
        if error.status_code in (401, 403):
            error_msg += " Please check your API key and secret."
        return error_msg
    
    # Default error handling
    return f"Error in {operation}: {str(error)}"

src/tools/schema.py:36-36 (registration)
The register_tools function in schema.py that defines and registers the get_doctype_schema tool using @mcp.tool() decorator.
```
def register_tools(mcp: Any) -> None:
```

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