Add agent configuration support with JSON/dict configs and tool name resolution

.gitignore

@@ -11,4 +11,5 @@ __pycache__*
 .vscode
 dist
 repl_state
-.kiro
+.kiro
+uv.lock

pyproject.toml

@@ -134,6 +134,7 @@ dependencies = [
     "pytest-asyncio>=1.0.0,<1.3.0",
     "pytest-xdist>=3.0.0,<4.0.0",
     "moto>=5.1.0,<6.0.0",
+    "strands-agents-tools>=0.2.0,<1.0.0",
 ]
 
 [[tool.hatch.envs.hatch-test.matrix]]

src/strands/experimental/__init__.py

@@ -2,3 +2,7 @@
 
 This module implements experimental features that are subject to change in future revisions without notice.
 """
+
+from .agent_config import AgentConfig
+
+__all__ = ["AgentConfig"]

src/strands/experimental/agent_config.py

@@ -0,0 +1,193 @@
+"""Experimental agent configuration with enhanced instantiation patterns."""
+
+import importlib
+import json
+from typing import TYPE_CHECKING, Any
+
+from ..tools.registry import ToolRegistry
+
+if TYPE_CHECKING:
+    # Import here to avoid circular imports:
+    # experimental/agent_config.py -> agent.agent -> event_loop.event_loop ->
+    # experimental.hooks -> experimental.__init__.py -> AgentConfig
+    from ..agent.agent import Agent
+
+# File prefix for configuration file paths
+FILE_PREFIX = "file://"
+
+# Minimum viable list of tools to enable agent building
+# This list is experimental and will be revisited as tools evolve
+DEFAULT_TOOLS = ["file_read", "editor", "http_request", "shell", "use_agent"]
+
+
+class AgentConfig:
+    """Agent configuration with to_agent() method and ToolRegistry integration.
+
+    Example config.json:
+    {
+        "model": "anthropic.claude-3-5-sonnet-20241022-v2:0",
+        "prompt": "You are a helpful assistant",
+        "tools": ["file_read", "editor"]
+    }
+    """
+
+    def __init__(
+        self,
+        config_source: str | dict[str, Any],
+        tool_registry: ToolRegistry | None = None,
+        raise_exception_on_missing_tool: bool = True,
+    ):
+        """Initialize AgentConfig from file path or dictionary.
+
+        Args:
+            config_source: Path to JSON config file (must start with 'file://') or config dictionary
+            tool_registry: Optional ToolRegistry to select tools from when 'tools' is specified in config
+            raise_exception_on_missing_tool: If False, skip missing tools instead of raising ImportError
+
+        Example:
+            # Dictionary config
+            config = AgentConfig({
+                "model": "anthropic.claude-3-5-sonnet-20241022-v2:0",
+                "prompt": "You are a helpful assistant",
+                "tools": ["file_read", "editor"]
+            })
+
+            # File config
+            config = AgentConfig("file://config.json")
+        """
+        if isinstance(config_source, str):
+            # Require file:// prefix for file paths
+            if not config_source.startswith(FILE_PREFIX):
+                raise ValueError(f"File paths must be prefixed with '{FILE_PREFIX}'")
+
+            # Remove file:// prefix and load from file
+            file_path = config_source.removeprefix(FILE_PREFIX)
+            with open(file_path, "r") as f:
+                config_data = json.load(f)
+        else:
+            # Use dictionary directly
+            config_data = config_source
+
+        self.model = config_data.get("model")
+        self.system_prompt = config_data.get("prompt")  # Only accept 'prompt' key
+        self._raise_exception_on_missing_tool = raise_exception_on_missing_tool
+
+        # Handle tool selection from ToolRegistry
+        if tool_registry is not None:
+            self._tool_registry = tool_registry
+        else:
+            # Create default ToolRegistry with strands_tools
+            self._tool_registry = self._create_default_tool_registry()
+
+        # Process tools configuration if provided
+        config_tools = config_data.get("tools")
+
+        # Track configured tools separately from full tool pool
+        self._configured_tools = []
+
+        # Apply tool selection if specified
+        if config_tools is not None:
+            # Validate all tool names exist in the ToolRegistry
+            available_tools = self._tool_registry.registry.keys()
+
+            missing_tools = set(config_tools).difference(available_tools)
+            if missing_tools and self._raise_exception_on_missing_tool:
+                raise ValueError(
+                    f"Tool(s) '{missing_tools}' not found in ToolRegistry. Available tools: {available_tools}"
+                )
+
+            for tool_name in config_tools:
+                if tool_name in self._tool_registry.registry:
+                    tool = self._tool_registry.registry[tool_name]
+                    self._configured_tools.append(tool)
+        # If no tools specified in config, use no tools (empty list)
+
+    def _create_default_tool_registry(self) -> ToolRegistry:
+        """Create default ToolRegistry with strands_tools."""
+        tool_registry = ToolRegistry()
+
+        try:
+            tool_modules = [importlib.import_module(f"strands_tools.{tool}") for tool in DEFAULT_TOOLS]
+            tool_registry.process_tools(tool_modules)
+        except ImportError as e:
+            if self._raise_exception_on_missing_tool:
+                raise ImportError(
+                    "strands_tools is not available and no ToolRegistry was specified. "
+                    "Either install strands_tools with 'pip install strands-agents-tools' "
+                    "or provide your own ToolRegistry with your own tools."
+                ) from e
+
+        return tool_registry
+
+    @property
+    def tool_registry(self) -> ToolRegistry:
+        """Get the full ToolRegistry (superset of all available tools).
+
+        Returns:
+            ToolRegistry instance containing all available tools
+        """
+        return self._tool_registry
+
+    @property
+    def configured_tools(self) -> list:
+        """Get the configured tools (subset selected for this agent).
+
+        Returns:
+            List of tools configured for this agent
+        """
+        return self._configured_tools
+
+    def to_agent(self, **kwargs: Any) -> "Agent":
+        """Create an Agent instance from this configuration.
+
+        Args:
+            **kwargs: Additional parameters to override config values.
+                     Supports all Agent constructor parameters.
+
+        Returns:
+            Configured Agent instance
+
+        Example:
+            # Using default tools from strands_tools
+            config = AgentConfig({
+                "model": "anthropic.claude-3-5-sonnet-20241022-v2:0",
+                "prompt": "You are a helpful assistant",
+                "tools": ["file_read"]
+            })
+            agent = config.to_agent()
+            response = agent("Read the contents of README.md")
+
+            # Using custom ToolRegistry
+            from strands import tool
+
+            @tool
+            def custom_tool(input: str) -> str:
+                return f"Custom: {input}"
+
+            custom_tool_registry = ToolRegistry()
+            custom_tool_registry.process_tools([custom_tool])
+            config = AgentConfig({
+                "model": "anthropic.claude-3-5-sonnet-20241022-v2:0",
+                "prompt": "You are a custom assistant",
+                "tools": ["custom_tool"]
+            }, tool_registry=custom_tool_registry)
+            agent = config.to_agent()
+        """
+        # Import at runtime since TYPE_CHECKING import is not available during execution
+        from ..agent.agent import Agent
+
+        # Start with config values
+        agent_params = {}
+
+        if self.model is not None:
+            agent_params["model"] = self.model
+        if self.system_prompt is not None:
+            agent_params["system_prompt"] = self.system_prompt
+
+        # Use configured tools (subset of tool pool)
+        agent_params["tools"] = self._configured_tools
+
+        # Override with any other provided kwargs
+        agent_params.update(kwargs)
+
+        return Agent(**agent_params)