I hope that why the following is purely a factual distinction, not an excuse or an attempt to empathize.
The difference between the other entities named and OpenCode is this:
OpenCode uses people’s Claude Code subscriptions. The other entities use the API.
Specifically, OpenCode reverse‑engineers Claude Code’s OAuth endpoints and API, then uses them. This is harmful from Anthropic's perspective because Claude Code is subsidized relative to the API.
Edit: I’m getting “You’re posting too fast” when replying to mr_mitm. For clarity, there is no separate API subscription. Anthropic wants you to use one of two funnels for coding with their LLMs: 1. The API (through any frontend), or 2. A subscription through an Anthropic‑owned frontend.