```ts type AgentConfig = { model?: | Model | ModelRouter | string; messages?: | Message[] | MessageData[]; tools?: ToolList; systemPrompt?: | SystemPrompt | SystemPromptData; appState?: Record; modelState?: Record; printer?: boolean; conversationManager?: ConversationManager; contextManager?: ContextManagerStrategy; plugins?: Plugin[]; backgroundTasks?: | boolean | BackgroundTasksConfig; retryStrategy?: | RetryStrategy | RetryStrategy[] | null; interventions?: InterventionHandler[]; structuredOutputSchema?: z.ZodSchema; sessionManager?: SessionManager; memoryManager?: | MemoryManager | MemoryManagerConfig; traceAttributes?: Record; name?: string; description?: string; id?: string; toolExecutor?: | ConcurrentToolExecutor | SequentialToolExecutor | ToolExecutorStrategy; checkpointing?: boolean; sandbox?: Sandbox | false; storage?: Storage; }; ``` Defined in: [src/agent/agent.ts:158](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L158) Configuration object for creating a new Agent. ## Properties ### model? ```ts optional model?: | Model | ModelRouter | string; ``` Defined in: [src/agent/agent.ts:181](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L181) The model instance or router that the agent will use to make decisions. Accepts a Model, ModelRouter, or a string representing a Bedrock model ID. When a router is provided, `agent.model` remains its default concrete model. #### Example ```typescript // Using a string model ID (creates BedrockModel) const agent = new Agent({ model: 'global.anthropic.claude-sonnet-4-6' }) // Using an explicit BedrockModel instance with configuration const agent = new Agent({ model: new BedrockModel({ modelId: 'global.anthropic.claude-sonnet-4-6', temperature: 0.7, maxTokens: 2048 }) }) ``` --- ### messages? ```ts optional messages?: | Message[] | MessageData[]; ``` Defined in: [src/agent/agent.ts:183](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L183) An initial set of messages to seed the agent’s conversation history. --- ### tools? ```ts optional tools?: ToolList; ``` Defined in: [src/agent/agent.ts:189](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L189) An initial set of tools to register with the agent. Accepts nested arrays of tools at any depth, which will be flattened automatically. [Agent](/docs/api/typescript/Agent/index.md) instances are automatically wrapped as tools via [Agent.asTool](/docs/api/typescript/Agent/index.md#astool). --- ### systemPrompt? ```ts optional systemPrompt?: | SystemPrompt | SystemPromptData; ``` Defined in: [src/agent/agent.ts:193](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L193) A system prompt which guides model behavior. --- ### appState? ```ts optional appState?: Record; ``` Defined in: [src/agent/agent.ts:195](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L195) Optional initial state values for the agent. --- ### modelState? ```ts optional modelState?: Record; ``` Defined in: [src/agent/agent.ts:200](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L200) Optional initial model-provider state (e.g., restoring `responseId` from a prior session). Typically only set when hydrating from a snapshot. --- ### printer? ```ts optional printer?: boolean; ``` Defined in: [src/agent/agent.ts:206](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L206) Enable automatic printing of agent output to console. When true, prints text generation, reasoning, and tool usage as they occur. Defaults to true. --- ### conversationManager? ```ts optional conversationManager?: ConversationManager; ``` Defined in: [src/agent/agent.ts:211](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L211) Conversation manager for handling message history and context overflow. Defaults to SlidingWindowConversationManager with windowSize of 40. --- ### contextManager? ```ts optional contextManager?: ContextManagerStrategy; ``` Defined in: [src/agent/agent.ts:225](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L225) Context management strategy that controls how messages are compressed and offloaded. - `"auto"`: Proactive truncation of tool results + summarization at 85% utilization. - `"agentic"`: (Experimental) Lets the model drive context management via injected tools, with a higher truncation threshold and summarization only on overflow. This mode may change in future versions. - `ContextManagerConfig` object: Custom strategy pipeline and stash configuration. - `false`: Explicitly disable context management (no compression, no offloading). When set (except `false`), any co-provided `conversationManager` is ignored. Defaults to undefined (SlidingWindowConversationManager). --- ### plugins? ```ts optional plugins?: Plugin[]; ``` Defined in: [src/agent/agent.ts:229](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L229) Plugins to register with the agent. --- ### backgroundTasks? ```ts optional backgroundTasks?: | boolean | BackgroundTasksConfig; ``` Defined in: [src/agent/agent.ts:231](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L231) Background tool execution configuration. --- ### retryStrategy? ```ts optional retryStrategy?: | RetryStrategy | RetryStrategy[] | null; ``` Defined in: [src/agent/agent.ts:242](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L242) Retry strategy (or strategies) for failed model/tool calls. - Omitted: a sensible default [DefaultModelRetryStrategy](/docs/api/typescript/DefaultModelRetryStrategy/index.md) with exponential backoff is used. - Single strategy: the given strategy is used. - Array of strategies: all are registered, in the given order. Passing two instances of the same concrete class logs a warning — they will collide on `plugin.name` when the plugin registry initializes. - `null` or `[]`: retries are explicitly disabled; failures propagate to the caller. --- ### interventions? ```ts optional interventions?: InterventionHandler[]; ``` Defined in: [src/agent/agent.ts:246](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L246) Intervention handlers evaluated in registration order at each lifecycle point. --- ### structuredOutputSchema? ```ts optional structuredOutputSchema?: z.ZodSchema; ``` Defined in: [src/agent/agent.ts:250](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L250) Zod schema for structured output validation. --- ### sessionManager? ```ts optional sessionManager?: SessionManager; ``` Defined in: [src/agent/agent.ts:254](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L254) Session manager for saving and restoring agent sessions --- ### memoryManager? ```ts optional memoryManager?: | MemoryManager | MemoryManagerConfig; ``` Defined in: [src/agent/agent.ts:260](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L260) Memory manager for cross-session memory retrieval and storage. Manages one or more memory stores and exposes search/add tools. Accepts a [MemoryManager](/docs/api/typescript/MemoryManager/index.md) instance or a [MemoryManagerConfig](/docs/api/typescript/MemoryManagerConfig/index.md) object (auto-wrapped). --- ### traceAttributes? ```ts optional traceAttributes?: Record; ``` Defined in: [src/agent/agent.ts:266](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L266) Custom trace attributes to include in all spans. These attributes are merged with standard attributes in telemetry spans. Telemetry must be enabled globally via telemetry.setupTracer() for these to take effect. --- ### name? ```ts optional name?: string; ``` Defined in: [src/agent/agent.ts:270](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L270) Optional name for the agent. Defaults to “Strands Agent”. --- ### description? ```ts optional description?: string; ``` Defined in: [src/agent/agent.ts:274](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L274) Optional description of what the agent does. --- ### id? ```ts optional id?: string; ``` Defined in: [src/agent/agent.ts:278](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L278) Optional unique identifier for the agent. Defaults to “agent”. --- ### toolExecutor? ```ts optional toolExecutor?: | ConcurrentToolExecutor | SequentialToolExecutor | ToolExecutorStrategy; ``` Defined in: [src/agent/agent.ts:286](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L286) Executor for tool calls from a single assistant turn. Accepts a [ConcurrentToolExecutor](/docs/api/typescript/ConcurrentToolExecutor/index.md), a [SequentialToolExecutor](/docs/api/typescript/SequentialToolExecutor/index.md), or the corresponding [ToolExecutorStrategy](/docs/api/typescript/ToolExecutorStrategy/index.md) string shorthand. Defaults to concurrent execution. --- ### checkpointing? ```ts optional checkpointing?: boolean; ``` Defined in: [src/agent/agent.ts:299](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L299) **`Experimental`** When `true`, the agent loop pauses at cycle boundaries (`afterModel`, `afterTools`) and returns `stopReason: 'checkpoint'` with a populated `checkpoint` field. Resume by passing the checkpoint back as `{ checkpointResume: { checkpoint: ... } }`. The SDK does not capture conversation state in the checkpoint; pair with a `SessionManager` for cross-process state continuity. Defaults to `false`. See the experimental checkpoint module. --- ### sandbox? ```ts optional sandbox?: Sandbox | false; ``` Defined in: [src/agent/agent.ts:313](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L313) Execution environment for running commands, code, and file operations. When provided, sandbox-aware tools route operations through it. Two distinct intents, even though they resolve to the same host execution in Node today: - Omitted: use the environment’s default sandbox (host execution in Node). This default is the slot reserved for richer behavior later. - `false`: explicitly opt out of a managed sandbox and run on the host. Keep `false` distinct from omitting so the opt-out stays stable even if the default changes. --- ### storage? ```ts optional storage?: Storage; ``` Defined in: [src/agent/agent.ts:323](https://github.com/strands-agents/harness-sdk/blob/3bbfb60ae79b3941305737c1c5ca1e7ef639361f/strands-ts/src/agent/agent.ts#L323) Default storage backend for agent subsystems. When provided, subsystems that do not have their own explicit storage (e.g., SessionManager, ContextManager) resolve from this value. Each subsystem auto-namespaces under its own prefix to avoid key collisions. Storage specified directly on a subsystem always takes precedence over this agent-level default.