Tools, MCP, and Sandboxes
In brief
Tools give an agent actions; MCP servers expose external tool surfaces; sandboxes isolate execution environments. They are related capabilities with different ownership and policy boundaries.
Ownership
An McpServer describes a namespaced endpoint, optional auth broker, and tool allowlist. Agent MCP references resolve by namespace ancestry, with the nearest same-named server winning. A SandboxClass identifies a provider, a SandboxPolicy selects the class and runtime template, and a Sandbox records the realized lease and processes.
Lifecycle
Workers resolve permitted tools for a turn, then apply server policy and agent capability policy. Sandbox policies control how isolated runtimes are leased and run; ACP-backed agents use those policies and their permission configuration rather than treating a container as an ambient tool.
Relationships
MCP is an external tool protocol, while a sandbox is execution isolation. Identity, Access, and Secrets distinguishes Talon access from tool-specific authentication. Setup and provider details belong in Operate.