Strands Agents is AWS's Apache-2.0 agent SDK, built around a model-driven loop where the model decides which tools to call. The Python SDK reached 1.0 in July 2025; a TypeScript version is in preview as of December 2025. Multi-agent composition supports workflow, graph, and swarm patterns, with sub-agents modeled as tools. It defaults to Amazon Bedrock but is model-agnostic: the launch post lists Anthropic's Claude, Llama, Ollama for local development, and others such as OpenAI through LiteLLM. MCP support is native; the launch framing is that an agent can draw on the published catalog of MCP servers for tools. For open-source AI, Strands is the AWS data point in the pattern of fully open vendor SDKs: the framework is Apache-2.0 and runs against open-weights models locally through Ollama, even though Bedrock is the house default. It is one of several 2026 SDKs that make the older "vendor SDK equals lock-in" assumption mostly false.
The Stack · Agents · Open source
Strands Agents
AWS's open agent SDK; Apache-2.0, Python (TypeScript in preview), Bedrock-default but model-agnostic, native MCP, workflow/graph/swarm multi-agent. 1.0 GA July 2025.
Sources
- Strands Agents documentation https://strandsagents.com/
- strands-agents/sdk-python LICENSE (Apache 2.0) https://raw.githubusercontent.com/strands-agents/sdk-python/main/LICENSE
- Introducing Strands Agents (launch, 2025-05-16) https://aws.amazon.com/blogs/opensource/introducing-strands-agents-an-open-source-ai-agents-sdk/
- Strands Agents multi-agent patterns docs https://strandsagents.com/docs/user-guide/concepts/multi-agent/multi-agent-patterns/
- TypeScript Strands Agents preview (2025-12-03) https://aws.amazon.com/about-aws/whats-new/2025/12/typescript-strands-agents-preview/
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