Astra is a versatile API specifically designed for functionality calls in Large Language Models (LLMs). It allows LLMs to perform operations in any target application through straightforward code integration, eliminating the need for complex JSON Schemas. Astra offers 2,200 ready-made integrations, connecting to tools like Google Calendar, Gmail, Hubspot, Salesforce, and more. Additionally, it features user authentication management, allowing LLMs to perform actions on behalf of users. Astra also supports easy import of REST integrations via OpenAPI specifications or the creation of custom integrations. This enables LLMs to interact with external tools or APIs to carry out practical tasks like data access, event scheduling, or email sending, making LLMs more interactive and powerful.