Merge branch 'a2a-url-new' of github.com:racinmat/adk-python into a2a-url-new

# Conflicts:
#	tests/unittests/a2a/utils/test_agent_to_a2a.py

Author: racinmat

contributing/samples/adk_agent_builder_assistant/README.md

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+# Agent Builder Assistant
+
+An intelligent assistant for building ADK multi-agent systems using YAML configurations.
+
+## Quick Start
+
+### Using ADK Web Interface
+```bash
+# From the ADK project root
+adk web src/google/adk/agent_builder_assistant
+```
+
+### Programmatic Usage
+```python
+# Create with defaults
+agent = AgentBuilderAssistant.create_agent()
+
+# Create with custom settings
+agent = AgentBuilderAssistant.create_agent(
+    model="gemini-2.5-pro",
+    schema_mode="query",
+    working_directory="/path/to/project"
+)
+```
+
+## Core Features
+
+### 🎯 **Intelligent Agent Design**
+- Analyzes requirements and suggests appropriate agent types
+- Designs multi-agent architectures (Sequential, Parallel, Loop patterns)
+- Provides high-level design confirmation before implementation
+
+### 📝 **Advanced YAML Configuration**
+- Generates AgentConfig schema-compliant YAML files
+- Supports all agent types: LlmAgent, SequentialAgent, ParallelAgent, LoopAgent
+- Built-in validation with detailed error reporting
+
+### 🛠️ **Multi-File Management**
+- **Read/Write Operations**: Batch processing of multiple files
+- **File Type Separation**: YAML files use validation tools, Python files use generic tools
+- **Backup & Recovery**: Automatic backups before overwriting existing files
+
+### 🗂️ **Project Structure Analysis**
+- Explores existing project structures
+- Suggests conventional ADK file organization
+- Provides path recommendations for new components
+
+### 🧭 **Dynamic Path Resolution**
+- **Session Binding**: Each chat session bound to one root directory
+- **Working Directory**: Automatic detection and context provision
+- **ADK Source Discovery**: Finds ADK installation dynamically (no hardcoded paths)
+
+## Schema Modes
+
+Choose between two schema handling approaches:
+
+### Embedded Mode (Default)
+```python
+agent = AgentBuilderAssistant.create_agent(schema_mode="embedded")
+```
+- Full AgentConfig schema embedded in context
+- Faster execution, higher token usage
+- Best for comprehensive schema work
+
+### Query Mode
+```python
+agent = AgentBuilderAssistant.create_agent(schema_mode="query")
+```
+- Dynamic schema queries via tools
+- Lower initial token usage
+- Best for targeted schema operations
+
+## Example Interactions
+
+### Create a new agent
+```
+Create an agent that can roll n-sided number and check whether the rolled number is prime.
+```
+
+### Add Capabilities to Existing Agent
+```
+Could you make the agent under `./config_based/roll_and_check` a multi agent system : root_agent only for request routing and two sub agents responsible for two functions respectively ?
+```
+
+### Project Structure Analysis
+```
+Please analyze my existing project structure at './config_based/roll_and_check' and suggest improvements for better organization.
+```
+
+## Tool Ecosystem
+
+### Core File Operations
+- **`read_config_files`** - Read multiple YAML configurations with analysis
+- **`write_config_files`** - Write multiple YAML files with validation
+- **`read_files`** - Read multiple files of any type
+- **`write_files`** - Write multiple files with backup options
+- **`delete_files`** - Delete multiple files with backup options
+
+### Project Analysis
+- **`explore_project`** - Analyze project structure and suggest paths
+- **`resolve_root_directory`** - Resolve paths with working directory context
+
+### ADK knowledge Context
+- **`google_search`** - Search for ADK examples and documentation
+- **`url_context`** - Fetch content from URLs (GitHub, docs, etc.)
+- **`search_adk_source`** - Search ADK source code with regex patterns
+
+
+## File Organization Conventions
+
+### ADK Project Structure
+```
+my_adk_project/
+└── src/
+    └── my_app/
+        ├── root_agent.yaml
+        ├── sub_agent_1.yaml
+        ├── sub_agent_2.yaml
+        ├── tools/
+        │   ├── process_email.py    # No _tool suffix
+        │   └── analyze_sentiment.py
+        └── callbacks/
+            ├── logging.py            # No _callback suffix
+            └── security.py
+```
+
+### Naming Conventions
+- **Agent directories**: `snake_case`
+- **Tool files**: `descriptive_action.py`
+- **Callback files**: `descriptive_name.py`
+- **Tool paths**: `project_name.tools.module.function_name`
+- **Callback paths**: `project_name.callbacks.module.function_name`
+
+## Session Management
+
+### Root Directory Binding
+Each chat session is bound to a single root directory:
+
+- **Automatic Detection**: Working directory provided to model automatically
+- **Session State**: Tracks established root directory across conversations
+- **Path Resolution**: All relative paths resolved against session root
+- **Directory Switching**: Suggest user starting new session to work in different directory
+
+### Working Directory Context
+```python
+# The assistant automatically receives working directory context
+agent = AgentBuilderAssistant.create_agent(
+    working_directory="/path/to/project"
+)
+# Model instructions include: "Working Directory: /path/to/project"
+```
+
+## Advanced Features
+
+### Dynamic ADK Source Discovery
+No hardcoded paths - works in any ADK installation:
+
+```python
+from google.adk.agent_builder_assistant.utils import (
+    find_adk_source_folder,
+    get_adk_schema_path,
+    load_agent_config_schema
+)
+
+# Find ADK source dynamically
+adk_path = find_adk_source_folder()
+
+# Load schema with caching
+schema = load_agent_config_schema()
+```
+
+### Schema Validation
+All YAML files validated against AgentConfig schema:
+
+- **Syntax Validation**: YAML parsing with detailed error locations
+- **Schema Compliance**: Full AgentConfig.json validation
+- **Best Practices**: ADK naming and structure conventions
+- **Error Recovery**: Clear suggestions for fixing validation errors
+
+## Performance Optimization
+
+### Efficient Operations
+- **Multi-file Processing**: Batch operations reduce overhead
+- **Schema Caching**: Global cache prevents repeated file reads
+- **Dynamic Discovery**: Efficient ADK source location caching
+- **Session Context**: Persistent directory binding across conversations
+
+### Memory Management
+- **Lazy Loading**: Schema loaded only when needed
+- **Cache Control**: Manual cache clearing for testing/development
+- **Resource Cleanup**: Automatic cleanup of temporary files
+
+## Error Handling
+
+### Comprehensive Validation
+- **Path Validation**: All paths validated before file operations
+- **Schema Compliance**: AgentConfig validation with detailed error reporting
+- **Python Syntax**: Syntax validation for generated Python code
+- **Backup Creation**: Automatic backups before overwriting files
+
+### Recovery Mechanisms
+- **Retry Suggestions**: Clear guidance for fixing validation errors
+- **Backup Restoration**: Easy recovery from automatic backups
+- **Error Context**: Detailed error messages with file locations and suggestions
+
+This comprehensive assistant provides everything needed for intelligent, efficient ADK agent system creation with proper validation, file management, and project organization.

contributing/samples/adk_agent_builder_assistant/__init__.py

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+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Agent Builder Assistant for ADK.
+
+This package provides an intelligent assistant for building multi-agent systems
+using YAML configurations. It can be used directly as an agent or integrated
+with ADK tools and web interfaces.
+"""
+
+from . import agent  # Import to make agent.root_agent available
+from .agent_builder_assistant import AgentBuilderAssistant
+
+__all__ = [
+    'AgentBuilderAssistant',
+    'agent',  # Make agent module available for adk web discovery
+]

contributing/samples/adk_agent_builder_assistant/agent.py

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+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Agent Builder Assistant instance for ADK web testing."""
+
+from .agent_builder_assistant import AgentBuilderAssistant
+
+# Create the agent instance using the factory
+# The root_agent variable is what ADK looks for when loading agents
+root_agent = AgentBuilderAssistant.create_agent()