Here’s what’s new on the Claude Developer Platform (API): - Claude Opus 4.5: The model is a meaningful step forward in what AI systems can do. It’s our most efficient model, and is available at $5 input / $25 output per million tokens—making Opus-level capabilities accessible to even more developers and enterprises. - Advanced tool use (beta): Build agents that can take action with three new capabilities—the tool search tool, programmatic tool calling, and tool use examples. Together, these updates enable Claude to navigate large tool libraries, chain operations efficiently, and accurately execute complex tasks. - Effort parameter (beta): Control how much effort Claude allocates across thinking, tool calls, and responses to balance performance, latency, and cost. - Context management capabilities: Enable agents to handle long-running tasks when using tools with the new compaction control SDK helper and reduce token consumption with thinking block preservation, now enabled by default.