Glossary
Workspace
A local project container in Sentinel. Usually backed by a folder on disk. Threads belong to a workspace.
Thread
The main unit of work in the app. A thread stores messages, mode, engine, model state, queued follow-ups, and repo-related state.
Chat mode
The default conversational work mode for a thread.
Plan mode
A structured thread mode with a stored plan document, tracked tasks, and question sets.
Engine
The runtime layer used for a thread. Sentinel supports sentinel, codex, claude, copilot, cursor, opencode, grok, antigravity, pi, and acp.
Engine instance
One configured copy of an agent: its label, binary, environment variables, custom models, and, where the agent has one, its home directory.
ACP
The Agent Client Protocol. Cursor, Grok Build, Antigravity, and ACP Registry agents talk to Sentinel over it.
Provider
The credential and connection layer for AI model access, such as OpenAI or Anthropic.
Model
A concrete model ID used through an engine and provider setup.
Worktree
A repo checkout path associated with a thread so work can stay isolated from the main local checkout.
Checkpoint
A saved repo state tied to thread history so earlier work can be restored or branched from.
Approval
A confirmation step required before a tool or group of tools can run.
Approval policy
The rule set attached to a thread runtime that decides when the runtime must stop and ask before acting.
Sandbox mode
The access level a runtime gets when it is acting on the local machine.
Skill
An installable capability pack that extends Sentinel, Claude, or Codex behavior.
MCP server
A Model Context Protocol server connected to Sentinel over STDIO or HTTP.
Integration
A built-in external system connection such as GitHub, Gmail, or PostgreSQL.
Automation
A recurring prompt tied to a workspace and runtime configuration that runs on a schedule.
Sub-agent
A delegated run linked back to a parent thread and stored with its own child state.
Project mode
The repo mode a thread is using, usually the main project checkout or a thread worktree.
Generated media
Image or video output produced through the app's media generation paths and served back to the UI as temporary artifacts.