sagents

Sagents

Sage Agents - Combining the wisdom of a Sage) with the power of LLM-based Agents

A sage is a person who has attained wisdom and is often characterized by sound judgment and deep understanding. Sagents brings this philosophy to AI agents: building systems that don't just execute tasks, but do so with thoughtful human oversight, efficient resource management, and extensible architecture.

Key Features

• Human-In-The-Loop (HITL) - Customizable permission system that pauses execution for approval on sensitive operations, including parallel tool calls where each action can be individually approved/rejected. Works across both main agents and SubAgents — interrupts propagate up to the parent for approval and resume seamlessly
• Composable Execution Modes - Agent run loops are explicit Elixir pipelines built from reusable steps. Mix and match built-in steps (call_llm, execute_tools, check_pre_tool_hitl, propagate_state, etc.) or write your own. Different agents can use different modes in the same application
• Structured Agent Completion (until_tool) - Force agents to loop until they call a specific tool, returning the result as a clean {:ok, state, %ToolResult{}} tuple. No more hoping the LLM follows your output format — get structured data you can pattern match on
• SubAgents - Delegate complex tasks to specialized child agents for efficient context management and parallel execution
• GenServer Architecture - Each agent runs as a supervised OTP process with automatic lifecycle management
• Phoenix.Presence Integration - Smart resource management that knows when to shut down idle agents
• PubSub Real-Time Events - Stream agent state, messages, and events to multiple LiveView subscribers
• Middleware System - Extensible plugin architecture for adding capabilities to agents, including composable observability callbacks for OpenTelemetry, metrics, or custom logging
• Cluster-Aware Distribution - Optional Horde-based distribution for running agents across a cluster of nodes with automatic state migration, or run locally on a single node (the default)
• State Persistence - Save and restore agent conversations via optional behaviour modules for agent state and display messages
• Virtual Filesystem - Isolated, in-memory file operations with optional persistence

See it in action! Try the agents_demo application to experience Sagents interactively, or add the sagents_live_debugger to your app for real-time insights into agent configuration, state, and event flows.

The AgentsDemo chat interface showing the use of a virtual filesystem, tool call execution, composable middleware, supervised Agentic GenServer assistant, and much more!

Create agent with middleware capabilities

{:ok, agent} = Agent.new(%{ agent_id: "my-agent-1", model: ChatAnthropic.new!(%{model: "claude-sonnet-4-5-20250929"}), base_system_prompt: "You are a helpful coding assistant.", middleware: [ TodoList, FileSystem, {HumanInTheLoop, [ interrupt_on: %{ "write_file" => true, "delete_file" => true } ]} ] }) ```