hooks
Hooks & Lifecycle
Agent extensibility via lifecycle hooks — intercept, observe, and control agent behavior at key points in the workflow
10 features
Session lifecycle management
Hooks for session start and end — initialize environment, load context, clean up resources, or log session activityGeneric tool use hooks
Pre and post hooks around any tool execution — inspect, modify, block, or log tool callsSubagent lifecycle
Hooks for when subagents are spawned and when they complete — observe delegation, aggregate results, enforce policiesControl shell commands
Dedicated hooks for intercepting shell/terminal command execution — block dangerous commands, audit, or inject env varsControl file access
Dedicated hooks for file read and write operations — enforce access policies, trigger linting, or audit file changesValidate prompts before submission
Intercept user prompts before they reach the model — block, rewrite, redact, annotate, or inject contextControl MCP tool use
Dedicated hooks for MCP server tool invocations — audit, restrict, or modify MCP tool calls independently from built-in toolsObserve compaction window
Hooks that fire before and after context window compaction — preserve critical state, log what gets summarized, or block compactionAgent complete (stop)
Hook that fires when the agent finishes a turn — implement quality gates, force continuation, or trigger follow-up workflowsAgent response tracking
Observe and react to the agent's responses — log output, track thinking, or trigger side effects after each messageinstructions
Instructions
How you tell the agent what to do — persistent guidance files, scoping, and cross-agent compatibility
6 features
mcp
Model Context Protocol
MCP client support — transports, server primitives, client features, and configuration
12 features
memory
Memory
How the agent persists its own knowledge and manages the constraint of limited context
3 features
tools
Built-in Tools
Native tools and capabilities the agent ships with out of the box
16 features
File read
Read file contents from the local filesystemFile edit / write
Create, modify, and overwrite filesNotebook editing
Read and edit Jupyter notebook (.ipynb) cellsCode search
Search file contents by pattern, regex, or filename globShell execution
Execute shell commands in the user's environmentBackground monitor
Run a process in the background and react to its output (tail logs, poll status)Scheduled tasks
Schedule recurring or one-shot prompts within a session (cron-like)Web search
Search the web for informationWeb fetch
Fetch and read the contents of a URLImage input
Read and understand images and screenshots (multimodal input)Image generation
Generate images from text descriptionsBrowser control
Programmatic browser interaction: take screenshots, navigate pages, click elementsLSP integration
Language server features: go-to-definition, find references, type errors, symbol searchSemantic search
Search codebase by meaning using embeddings or indexing, not just exact matchesSubagent spawning
Spawn sub-agents with their own context window to handle tasks in parallelTask management
Track work progress with task lists and checklists within a session