OpenCode is an open-source coding agent that runs in your terminal, a desktop app, or an IDE extension, connecting to 75+ LLM providers including local models. You can spin up multiple agents on the same project in parallel, share debug sessions via a link, and log in with your existing GitHub Copilot or ChatGPT Plus credentials rather than paying again. The no-data-storage architecture makes it viable in privacy-sensitive environments where cloud-only tools are ruled out. The ceiling shows up when you need validated, consistent model performance out of the box — that lives behind the paid Zen add-on, not in the free tier.