Inject agent session info into context

python/packages/kagent-adk/src/kagent/adk/cli.py

@@ -15,7 +15,7 @@
 from kagent.core import KAgentConfig, configure_logging, configure_tracing
 
 from . import AgentConfig, KAgentApp
-from .tools import add_skills_tool_to_agent
+from .tools import add_session_tool, add_skills_tool_to_agent
 
 logger = logging.getLogger(__name__)
 logging.getLogger("google_adk.google.adk.tools.base_authenticated_tool").setLevel(logging.ERROR)
@@ -74,7 +74,7 @@ def static(
 
     def root_agent_factory() -> BaseAgent:
         root_agent = agent_config.to_agent(app_cfg.name, sts_integration)
-
+        add_session_tool(root_agent)
         maybe_add_skills(root_agent)
 
         return root_agent
@@ -149,6 +149,7 @@ def root_agent_factory() -> BaseAgent:
         if sts_integration:
             add_to_agent(sts_integration, root_agent)
 
+        add_session_tool(root_agent)
         maybe_add_skills(root_agent)
 
         return root_agent
@@ -213,6 +214,7 @@ async def test_agent(agent_config: AgentConfig, agent_card: AgentCard, task: str
 
     def root_agent_factory() -> BaseAgent:
         root_agent = agent_config.to_agent(app_cfg.name, sts_integration)
+        add_session_tool(root_agent)
         maybe_add_skills(root_agent)
         return root_agent
 

python/packages/kagent-adk/src/kagent/adk/tools/README.md

@@ -123,6 +123,7 @@ description: Analyze CSV/Excel files
 | **ReadFile**   | Read files with line numbers | `read_file("skills/data-analysis/config.json")`       |
 | **WriteFile**  | Create/overwrite files       | `write_file("outputs/report.pdf", data)`              |
 | **EditFile**   | Precise string replacements  | `edit_file("script.py", old="x", new="y")`            |
+| **SessionInfo**| Auto-injects session details into system instructions | *(automatic — no tool call needed)*                     |
 
 ### Working Directory Structure
 

python/packages/kagent-adk/src/kagent/adk/tools/__init__.py

@@ -1,5 +1,6 @@
 from .bash_tool import BashTool
 from .file_tools import EditFileTool, ReadFileTool, WriteFileTool
+from .session_tool import SessionInfoTool, add_session_tool
 from .skill_tool import SkillsTool
 from .skills_plugin import add_skills_tool_to_agent
 from .skills_toolset import SkillsToolset
@@ -8,8 +9,10 @@
     "SkillsTool",
     "SkillsToolset",
     "BashTool",
+    "SessionInfoTool",
     "EditFileTool",
     "ReadFileTool",
     "WriteFileTool",
+    "add_session_tool",
     "add_skills_tool_to_agent",
 ]

python/packages/kagent-adk/src/kagent/adk/tools/session_tool.py

@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+import logging
+from typing import TYPE_CHECKING
+
+from google.adk.agents import BaseAgent, LlmAgent
+from google.adk.tools.base_tool import BaseTool
+from google.adk.tools.tool_context import ToolContext
+from typing_extensions import override
+
+if TYPE_CHECKING:
+    from google.adk.models.llm_request import LlmRequest
+
+logger = logging.getLogger("kagent_adk." + __name__)
+
+
+def add_session_tool(agent: BaseAgent) -> None:
+    if not isinstance(agent, LlmAgent):
+        return
+    existing_tool_names = {getattr(t, "name", None) for t in agent.tools}
+    if "get_session_info" not in existing_tool_names:
+        agent.tools.append(SessionInfoTool())
+        logger.debug(f"Added session info tool to agent: {agent.name}")
+
+
+class SessionInfoTool(BaseTool):
+    """Tool for retrieving information about the current agent session."""
+
+    def __init__(self):
+        super().__init__(
+            name="get_session_info",
+            description="Get information about the current agent session, including the session ID.",
+        )
+
+    @override
+    async def process_llm_request(
+        self,
+        *,
+        tool_context: ToolContext,
+        llm_request: LlmRequest,
+    ) -> None:
+        session = tool_context.session
+        if not session:
+            return
+        info = (
+            "kagent session:\n"
+            f"- session_id: {session.id or 'N/A'}\n"
+            f"- user_id: {session.user_id or 'N/A'}\n"
+            f"- app_name: {session.app_name or 'N/A'}"
+        )
+        llm_request.append_instructions([info])

python/packages/kagent-adk/src/kagent/adk/tools/skills_toolset.py

@@ -13,7 +13,7 @@
 from google.adk.tools import BaseTool
 from google.adk.tools.base_toolset import BaseToolset
 
-from ..tools import BashTool, EditFileTool, ReadFileTool, WriteFileTool
+from ..tools import BashTool, EditFileTool, ReadFileTool, SessionInfoTool, WriteFileTool
 from .skill_tool import SkillsTool
 
 logger = logging.getLogger("kagent_adk." + __name__)
@@ -28,6 +28,7 @@ class SkillsToolset(BaseToolset):
     3. WriteFileTool - Write/create files
     4. EditFileTool - Edit files with precise replacements
     5. BashTool - Execute shell commands
+    6. SessionInfoTool - Inject session information into system instructions
 
     Skills provide specialized domain knowledge and scripts that the agent can use
     to solve complex tasks. The toolset enables discovery of available skills,
@@ -51,18 +52,20 @@ def __init__(self, skills_directory: str | Path):
         self.write_file_tool = WriteFileTool()
         self.edit_file_tool = EditFileTool()
         self.bash_tool = BashTool(skills_directory)
+        self.session_info_tool = SessionInfoTool()
 
     @override
     async def get_tools(self, readonly_context: Optional[ReadonlyContext] = None) -> List[BaseTool]:
         """Get all skills tools.
 
         Returns:
-          List containing all skills tools: skills, read, write, edit, and bash.
+          List containing all skills tools: skills, read, write, edit, bash, and session info.
         """
         return [
             self.skills_tool,
             self.read_file_tool,
             self.write_file_tool,
             self.edit_file_tool,
             self.bash_tool,
+            self.session_info_tool,
         ]

python/packages/kagent-adk/tests/unittests/test_session_tool.py

@@ -0,0 +1,52 @@
+# Copyright 2026 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.
+
+from unittest.mock import Mock
+
+import pytest
+from google.adk.models.llm_request import LlmRequest
+
+from kagent.adk.tools.session_tool import SessionInfoTool
+
+
+class TestSessionInfoTool:
+    @pytest.mark.asyncio
+    async def test_session_info_tool(self):
+        tool = SessionInfoTool()
+
+        context = Mock()
+        context.session = Mock()
+        context.session.id = "session-123"
+        context.session.user_id = "user-456"
+        context.session.app_name = "test-app"
+
+        llm_request = LlmRequest()
+        await tool.process_llm_request(tool_context=context, llm_request=llm_request)
+
+        assert "session-123" in llm_request.config.system_instruction
+        assert "user-456" in llm_request.config.system_instruction
+        assert "test-app" in llm_request.config.system_instruction
+        assert "get_session_info" not in llm_request.tools_dict
+
+    @pytest.mark.asyncio
+    async def test_session_info_tool_none_session(self):
+        tool = SessionInfoTool()
+
+        context = Mock()
+        context.session = None
+
+        llm_request = LlmRequest()
+        await tool.process_llm_request(tool_context=context, llm_request=llm_request)
+
+        assert llm_request.config.system_instruction is None