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Shell

Execute shell commands from your agent. Supports timeouts, output truncation, and an optional command allowlist for safety.

Quick Start


Config

string
Shell to use (default: platform default, e.g. /bin/sh).
number
default:"30000"
Command timeout in milliseconds.
number
default:"10000"
Max output characters to return. Long output is truncated from the start.
string
Working directory for commands.
string[]
Allowlist of command prefixes. If set, only commands starting with one of these are permitted.

Tools


Security

The Shell toolkit includes built-in protections against command injection:
  • Metacharacter rejection: Commands containing shell metacharacters (;, |, &, `, $, (, ), {, }, \, <, >, newlines) are automatically rejected before execution — even if they pass the allowlist check.
  • Allowlist enforcement: When allowedCommands is set, only commands starting with an allowed prefix are permitted.
These protections prevent an LLM from chaining commands, piping to other processes, or using shell expansion in arguments.
Always set allowedCommands in production to restrict which commands agents can run. Without it, the agent can execute any single command (subject to metacharacter validation).
See the Security page for a full overview of security hardening across Agentium.