```ts type AgentConfig = { model?: | Model | string; messages?: | Message[] | MessageData[]; tools?: ToolList; systemPrompt?: | SystemPrompt | SystemPromptData; appState?: Record; modelState?: Record; printer?: boolean; conversationManager?: ConversationManager; contextManager?: ContextManagerStrategy; plugins?: Plugin[]; 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:170](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L170) Configuration object for creating a new Agent. ## Properties ### model? ```ts optional model?: | Model | string; ``` Defined in: [src/agent/agent.ts:193](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L193) The model instance that the agent will use to make decisions. Accepts either a Model instance or a string representing a Bedrock model ID. When a string is provided, it will be used to create a BedrockModel instance. #### 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:195](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L195) An initial set of messages to seed the agent’s conversation history. --- ### tools? ```ts optional tools?: ToolList; ``` Defined in: [src/agent/agent.ts:201](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L201) An initial set of tools to register with the agent. Accepts nested arrays of tools at any depth, which will be flattened automatically. [Agent](/pr-cms-3708/docs/api/typescript/Agent/index.md) instances are automatically wrapped as tools via [Agent.asTool](/pr-cms-3708/docs/api/typescript/Agent/index.md#astool). --- ### systemPrompt? ```ts optional systemPrompt?: | SystemPrompt | SystemPromptData; ``` Defined in: [src/agent/agent.ts:205](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L205) A system prompt which guides model behavior. --- ### appState? ```ts optional appState?: Record; ``` Defined in: [src/agent/agent.ts:207](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L207) Optional initial state values for the agent. --- ### modelState? ```ts optional modelState?: Record; ``` Defined in: [src/agent/agent.ts:212](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L212) 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:218](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L218) 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:223](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L223) 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:238](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L238) Context management strategy. - `"auto"`: SummarizingConversationManager with proactive compression + ContextOffloader. - `"agentic"`: (Experimental) Lets the model drive context management via injected tools. This mode may change in future versions. If `conversationManager` is also provided, the user’s conversation manager is used instead. Defaults to undefined (SlidingWindowConversationManager, no offloader). #### Remarks The offloader uses in-memory storage by default. When an agent-level `storage` is provided, the offloader uses that instead. Alternatively, provide an explicit `ContextOffloader` with its own storage via the `plugins` parameter. --- ### plugins? ```ts optional plugins?: Plugin[]; ``` Defined in: [src/agent/agent.ts:242](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L242) Plugins to register with the agent. --- ### retryStrategy? ```ts optional retryStrategy?: | RetryStrategy | RetryStrategy[] | null; ``` Defined in: [src/agent/agent.ts:253](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L253) Retry strategy (or strategies) for failed model/tool calls. - Omitted: a sensible default [DefaultModelRetryStrategy](/pr-cms-3708/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:257](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L257) Intervention handlers evaluated in registration order at each lifecycle point. --- ### structuredOutputSchema? ```ts optional structuredOutputSchema?: z.ZodSchema; ``` Defined in: [src/agent/agent.ts:261](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L261) Zod schema for structured output validation. --- ### sessionManager? ```ts optional sessionManager?: SessionManager; ``` Defined in: [src/agent/agent.ts:265](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L265) Session manager for saving and restoring agent sessions --- ### memoryManager? ```ts optional memoryManager?: | MemoryManager | MemoryManagerConfig; ``` Defined in: [src/agent/agent.ts:271](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L271) Memory manager for cross-session memory retrieval and storage. Manages one or more memory stores and exposes search/add tools. Accepts a [MemoryManager](/pr-cms-3708/docs/api/typescript/MemoryManager/index.md) instance or a [MemoryManagerConfig](/pr-cms-3708/docs/api/typescript/MemoryManagerConfig/index.md) object (auto-wrapped). --- ### traceAttributes? ```ts optional traceAttributes?: Record; ``` Defined in: [src/agent/agent.ts:277](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L277) 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:281](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L281) Optional name for the agent. Defaults to “Strands Agent”. --- ### description? ```ts optional description?: string; ``` Defined in: [src/agent/agent.ts:285](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L285) Optional description of what the agent does. --- ### id? ```ts optional id?: string; ``` Defined in: [src/agent/agent.ts:289](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L289) Optional unique identifier for the agent. Defaults to “agent”. --- ### toolExecutor? ```ts optional toolExecutor?: | ConcurrentToolExecutor | SequentialToolExecutor | ToolExecutorStrategy; ``` Defined in: [src/agent/agent.ts:297](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L297) Executor for tool calls from a single assistant turn. Accepts a [ConcurrentToolExecutor](/pr-cms-3708/docs/api/typescript/ConcurrentToolExecutor/index.md), a [SequentialToolExecutor](/pr-cms-3708/docs/api/typescript/SequentialToolExecutor/index.md), or the corresponding [ToolExecutorStrategy](/pr-cms-3708/docs/api/typescript/ToolExecutorStrategy/index.md) string shorthand. Defaults to concurrent execution. --- ### checkpointing? ```ts optional checkpointing?: boolean; ``` Defined in: [src/agent/agent.ts:310](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L310) **`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:324](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L324) 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:334](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/agent/agent.ts#L334) Default storage backend for agent subsystems. When provided, subsystems that do not have their own explicit storage (e.g., SessionManager, ContextOffloader) resolve from this value. Each subsystem auto-namespaces under its own prefix (`session/`, `offloader/`) to avoid key collisions. Storage specified directly on a subsystem always takes precedence over this agent-level default.