Python imports

Import each capability from its public domain module. The examples in this documentation use these paths so you can find related types and operations in one place:

from harnest.agent import Agent
from harnest.auth import AuthPrincipal, AuthenticationError
from harnest.lifecycle import lifecycle
from harnest.sandbox import Sandbox, control
from harnest.tool import tool, client_tool

Domain imports

Capability	Public module	Examples
Agents and graphs	`harnest.agent`, `harnest.graph`	`Agent`, `Graph`, `Edge`
Authentication	`harnest.auth`	`AuthPrincipal`, `Authenticator`, `AuthenticationError`, `principal_for`
HTTP endpoints and hooks	`harnest.http`	`AgentInvoker`, `AgentResponse`, `HTTPCallRequest`, `HTTPLifecycleContext`
Server configuration	`harnest.server`	`ServerConfig`, `ServerLimits`, `load_server_config`
Tools	`harnest.tool`	`tool`, `client_tool`, `ClientToolError`, `ToolCallRequest`, `ToolLifecycleContext`
MCP	`harnest.mcp`	`MCPClient`, `MCPContext`, `MCPToolCallRequest`, `MCPToolCallError`
Models	`harnest.model`	`LiteLLMModel`, `LiteLLMContext`, `ModelCallRequest`, `ModelLifecycleError`
Lifecycle	`harnest.lifecycle`	`lifecycle`, `Next`, `Finish`, `LifecycleCoverage`, `CoverageLevel`
Invocation context	`harnest.context`	`context`, `SessionContext`, `StorageContext`, `ScopedAssets`, `AgentSession`
Sandbox providers	`harnest.sandbox`	`Sandbox`, `SandboxResult`, `SandboxCancelledError`, `control`
Runtime adapters	`harnest.runtime`	`ResponseRequest`, `InvocationRequest`, `RuntimeDriver`, `RuntimeEvent`
Assets	`harnest.assets`	`AssetStorage`, `AssetScope`, `Stored`
Storage	`harnest.store`	`MemoryStore`, `PostgresStore`, `RedisStore`, `CustomStorage`, `StorageRegistry`

Other existing domain modules include harnest.approval, harnest.content, harnest.credentials, harnest.continuation, harnest.extensions, harnest.skills, harnest.task, harnest.logging, and harnest.tracing. AgentResponse from harnest.http represents an HTTP route response. AgentResponse from harnest.context represents a local agent invocation response; select the contract for your integration.

Scoped operations

Sandbox execution and cleanup share a namespace:

from harnest.sandbox import control

with control.execute(timeout_seconds=30) as execution:
    execution.check()
    # Perform provider work with execution.remaining() as the I/O budget.

with control.cleanup(timeout_seconds=5) as cleanup:
    cleanup.check()
    # Release owned resources using cleanup.remaining() as the I/O budget.

control.current() returns the active scope. See sandbox failure recovery and cleanup for cancellation and deadline guarantees. Query lifecycle coverage with the same domain pattern:

from harnest.lifecycle import lifecycle

coverage = lifecycle.coverage("langgraph", "managed")

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Python imports

Domain imports

Scoped operations

​Domain imports

​Scoped operations

Domain imports

Scoped operations