Claude AI Now Executes Code in Real-Time (Sandboxed Python/Node.js) (tolearn.blog)

Anthropic announced that Claude can now write and execute Python and Node.js code in a sandboxed environment directly in the browser and desktop app (update rolled out Sept 14, 2025). Beyond code execution, Claude can create and edit Office/PDF files, process CSV/JSON/Excel datasets, generate visualizations and reports, and run iterative debug cycles all inside the chat interface. That collapses the old prompt → code → test loop into a single, real-time feedback loop: drop in fixtures or datasets, ask Claude to exercise paths or validate behavior, and get instant logs, charts, and corrected code. Technically, execution runs in isolated sandboxes with resource limits, clean state per run, and multi-language support (currently Python and Node.js) to mitigate system access and runaway workloads. The update accelerates prototyping, lowers the learning curve for juniors, and enables agentic workflows where Claude can iterate and self-correct with minimal human intervention. It also raises practical concerns: uploaded data traverses Anthropic servers (compliance/data governance), prompt-injection and over-reliance risks persist, and access is regionally restricted for security reasons. Teams should pilot low-risk use cases, pair Claude with CI and test suites, and harden governance/audit controls while competitors rush to match real-time execution as a new baseline for AI coding tools.