Bash Tool for ADK¶
The ExecuteBashTool allows an ADK agent to execute bash commands within a local workspace directory. This tool is useful for file system operations, running scripts, or interacting with the local environment directly through the agent.
The tool is only available for Python ADK.
Installation¶
The Bash Tool is included by default in the core Agent Development Kit (ADK). You don't need to install any separate integration packages; simply install the main library:
Use with agent¶
POSIX-only
ExecuteBashTool is currently supported only on POSIX systems such as Linux or macOS. Executing this tool on a Windows system will result in a hard error.
To use the Bash Tool, instantiate ExecuteBashTool and include it in your agent's tools list. Ensure my_workspace_path is defined prior to running the snippet as a valid directory path string:
from google.adk.tools.bash_tool import ExecuteBashTool, BashToolPolicy
policy = BashToolPolicy(
allowed_command_prefixes=("ls", "cat", "grep"),
timeout_seconds=30,
max_memory_bytes=1024 * 1024 * 512, # 512MB
max_file_size_bytes=1024 * 1024 * 10, # 10MB
max_child_processes=5
)
tool = ExecuteBashTool(workspace=my_workspace_path, policy=policy)
Security and execution safeguards¶
Because executing arbitrary code carries inherent risks, the ExecuteBashTool includes several mandatory and optional security features enforced upon the spawned subprocess.
Default policy allows all commands¶
By default, BashToolPolicy is initialized with allowed_command_prefixes=("*",). This means that all commands are permitted by default. To secure your application, you must explicitly restrict the allowed commands when initializing the policy:
# Secure implementation example
from google.adk.tools.bash_tool import BashToolPolicy
strict_policy = BashToolPolicy(
allowed_command_prefixes=("ls ", "cat ", "pwd")
)
Built-in protections¶
- User Confirmation: The tool always requests user confirmation before executing a command. The framework pauses execution and waits for the user or client application to approve the command via the
adk_request_confirmationflow. - Command Validation: You can whitelist specific commands using
allowed_command_prefixesand strictly forbid certain string patterns usingblocked_operators. - Resource Limits: OS-level limits,
setrlimit, are applied to restrict memory consumption, file sizes, and the number of child processes to prevent fork bombs or memory exhaustion. - Core Dumps Disabled: To prevent sensitive memory leaks, core dumps are strictly disabled,
RLIMIT_COREset to0, for the executing subprocess. - Process Group Termination: If a command exceeds the
timeout_seconds, the tool issues aSIGKILLto the entire process group to ensure no orphan background processes are left running.
Available tools¶
| Tool Name | Class Name | Description |
|---|---|---|
execute_bash |
ExecuteBashTool |
Executes a bash command within a workspace. POSIX only |