Anatomy of a coding agent: the harness behind Mastra Code

Everyone in the coding-agent space has built or forked an agent loop, but Mastra Code wraps that foundation with a harness that manages conversation-as-channel, event-to-display-state translation, human-in-the-loop tools, observational memory, subagents, modes, and an ordered tool-approval chain. The article details how maintaining coherence across extended sessions requires this additional harness layer beyond the basic loop.