Greptile Uses OpenAI GPT-6 Astra to Automate App Testing

According to OpenAI, Greptile is using the GPT-6 Astra model to automate application testing beyond code review. The company builds AI agents that review and test code changes with full context of the codebase, and OpenAI says GPT-6 Astra's computer use gives Greptile a way to automate testing at scale.

OpenAI states that validating a pull request involves checking whether the code is logically correct, does what the developer intended, is secure, and avoids breaking existing functionality. For some of that testing, running the application is necessary because reading the code alone might not reveal the problem. Greptile Co-founder and CEO Daksh Gupta gives the example of a button that disappears when a website is viewed on an iPhone. According to OpenAI, with GPT-6 Astra, Greptile can start a development server for a pull request, resize the browser to an iPhone-sized viewport, and simulate a user moving through the application. The model's visual understanding lets it inspect the screen and spot the hidden button.

Beyond GPT-6 Astra, Greptile uses several other OpenAI products:

• Daybreak: Gupta says Greptile uses Daybreak to provide defense mechanisms that help customers, including startups, secure their systems against application exploits.
• Codex: Greptile makes its Knowledge Base - which indexes a company's codebase and documents how it works in a form people and agents can read - available to Codex through a Model Context Protocol (MCP) server. According to OpenAI, this allows Codex to write code that follows the customer's existing patterns, and Gupta says thousands of customers have connected Codex to Greptile's knowledge base. To measure the impact, the team tracks how often AI-generated code is reverted. Gupta says that when Greptile provides agents with context, fewer reverts happen and customers save time and inference.
• Ultrafast: Gupta says model intelligence is already sufficient for many tasks, so he sees Ultrafast as a way to speed up how quickly the team can turn ideas into working software.

According to Gupta, Greptile also uses Codex internally across its functions, particularly engineering, to build its own software and agents. Gupta's longer-term goal is to make changing and shipping critical enterprise software as easy as shipping a side project, with OpenAI helping Greptile build the validation that requires. OpenAI states that more than 1 million businesses around the world use its technology.