compatible
Use the known object model
Agents, environments, sessions, events, vaults, resources, and tools stay recognizable to teams already evaluating Claude Managed Agents.
Claude Managed Agents alternative
Managed Agents
on Sandbox0
Sandbox0 Managed Agents is a Claude Managed Agents-compatible backend. Use the official Anthropic SDK and the familiar agents, environments, sessions, events, vaults, and resources model, while Sandbox0 owns execution, persistence, and policy underneath.
Prompt for your agent
Read https://sandbox0.ai/llms.txt and evaluate Sandbox0 Managed Agents for my backend. Check session durability, harness choices, sandbox-as-tool vs agent-in-sandbox, vaults, runtime policy, SDK compatibility, and open risks.
Compatibility stack
sdk
Official Anthropic SDK
Client code keeps the Claude Managed Agents SDK shape and points baseURL at Sandbox0.
api
Sandbox0 Managed Agents
Session truth, event history, observability traces, vaults, resources, and runtime callbacks live outside the sandbox.
harness
Claude / Codex / SandPi
Choose the agent harness behind the session while keeping one managed-agents API surface.
Why it exists
Claude Managed Agents made the model clear. Sandbox0 makes it portable.
The useful abstraction is not tied to one hosted runtime. Sandbox0 implements the backend shape around durable sessions, sandbox execution, and explicit credential boundaries.
backend
Inspect the execution layer
Session state and observability data are durable outside the sandbox, while Sandbox0 claims or resumes execution attachments as work arrives.
vendor choice
Separate API shape from runtime choice
Pick the model provider and agent harness that fits the workload instead of binding every session to one hosted vendor path.
Agent harnesses
One managed-agents surface, multiple runtime models.
Internally these are agent harnesses. Externally, the important point is that Sandbox0 can run both agent-in-sandbox and sandbox-as-tool harness families behind the same managed-agents API.
claude
Claude Agent SDK
Anthropic-compatible behavior for teams that want Claude Code-style agent execution behind a managed session API.
codex
Codex app-server
OpenAI-compatible Codex sessions with thread state stored under the Sandbox0 session workspace.
sandpi
SandPi
A Sandbox0-native brain/hands split harness with a resident agent loop and Sandbox0 as the hands execution environment.
Execution models
Split the agent brain from sandbox hands when latency matters.
Some harnesses keep the agent process inside the sandbox. Others keep the agent loop in a resident runtime and claim a Sandbox0 sandbox only for tool execution.
agent-in-sandbox
Claude and Codex
Use this model when the harness expects local files, shell state, home-directory state, and long-lived process state inside the workspace.
sandbox-as-tool
SandPi
Use this model when product control planes should keep the agent loop resident and claim Sandbox0 only for hands execution.
provider shape
Match the LLM protocol
Claude expects Anthropic Messages-compatible endpoints; Codex and SandPi expect OpenAI-compatible provider endpoints while using different execution placement.
Sandbox0 underneath
The managed layer still runs on real sandbox infra.
Managed Agents is simpler to call, but it does not hide the hard infrastructure problems. It packages them behind a durable API model.
sessions
Durable session truth
Event logs, trace timelines, model spans, tool calls, and session status live outside the sandbox so runs can resume and remain inspectable.
workspace
Persistent workspace
Resources, harness state, files, and artifacts survive across turns through Sandbox0 volumes.
vaults
Credential vaults
Model and service credentials belong in vaults, not inside SDK clients or agent source code.
policy
Runtime policy
Network policy and egress auth are enforced by Sandbox0 instead of the harness process.
Use Claude Managed Agents semantics on Sandbox0 infra.
Point the official SDK at Sandbox0 and run managed sessions on infrastructure designed for persistent AI agents.