Monitor T3 Code with FrontierStack

T3 Code is an open-source (MIT) control surface for the coding agents already on your Mac; Codex, Claude Code, Cursor, Grok Build and OpenCode; with desktop, web and mobile front ends. FrontierStack finds the local T3 Code server wherever it listens and, once you connect it with a read-only token, shows every thread that is waiting for you (an approval or a question), working or failed, with its project, provider, model and branch; today's tokens and estimated cost by model; and the CPU and memory of T3 Code and every agent it runs. Waiting threads reach the Agent Activity inbox and your paired iPhone, and T3 Code gets its own tile on the AI Agents board of the Server Activity window. The token FrontierStack keeps can only read: it can't start work, answer an approval or open a terminal. T3 Code workers on your servers are detected too.