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Anthropic maintains official client SDKs for Python, TypeScript, Go, Java, Ruby, PHP, and C#, plus a command-line CLI and direct cURL access. All SDKs wrap the same underlying Messages API and support the full feature set including streaming, tool use, vision, and extended thinking. This multi-language coverage is broader than many competing LLM providers and eliminates the need for community-maintained wrappers in most backend stacks. Each SDK follows idiomatic conventions for its language, making integration straightforward for teams.
The Messages API gives you direct model access where you construct every conversation turn, manage conversation state yourself, and write your own tool loop — ideal for developers who want full control. Claude Managed Agents, by contrast, is fully managed agent infrastructure that deploys autonomous agents with stateful sessions and persistent event history, removing the need to build your own orchestration layer. Teams typically start with Messages for prototyping and migrate to Managed Agents when they need production-grade stateful behavior. Both surfaces use the same underlying Claude models and pricing.
The SDK exposes three main models: Claude Opus 4.6 (claude-opus-4-6) for the most complex analysis, coding, and deep reasoning tasks; Claude Sonnet 4.6 (claude-sonnet-4-6) for balanced intelligence and speed suitable for most production workloads; and Claude Haiku 4.5 (claude-haiku-4-5) for lightning-fast, high-volume, latency-sensitive applications. A common pattern is to prototype on Sonnet, escalate to Opus for hard subtasks, and use Haiku for classification or routing. Model selection is done by passing the model ID string in each API call, so you can mix models within a single application.
Yes — the SDK provides a comprehensive tool use system including built-in tools for web search, web fetch, code execution, bash, computer use, text editor, and memory, alongside full support for custom developer-defined tools and programmatic tool calling. It also supports the Model Context Protocol (MCP) through remote MCP servers and an MCP connector, allowing Claude to interface with external systems in a standardized way. Fine-grained tool streaming lets you process tool calls as they are generated, which is important for building responsive agents. These capabilities are specifically designed to support long-horizon agentic workflows.
Yes, Anthropic offers first-party deployment through Amazon Bedrock, Google Cloud Vertex AI, and Microsoft Foundry in addition to the direct Anthropic API. These cloud integrations are useful for enterprise teams with existing procurement, billing, or data residency requirements tied to a specific cloud provider. Feature parity with the direct API is generally high, though some newer features may launch on the direct API first before rolling out to cloud partners. The same SDKs can typically be pointed at the cloud endpoints with minimal configuration changes.
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Last verified March 2026