ADR-0069: Claude is an installable provider; echo is the only built-in

• Status: Accepted
• Date: 2026-09-04
• Deciders: jka
• Decision: D69

Context

ADR-0066 moved OpenAI out of the tree but kept Claude in-tree as an always-present provider. The maintainer's intent was that agent integration belongs to rio while individual LLM providers are extensions. Keeping one provider inside and one outside blurred that line.

Decision

Claude installs as a kind = provider extension from extensions/claude/, exactly like OpenAI. The core ships only the offline echo provider. A real agent, including on the maintainer's own development core, is installed from a repository and activated on restart.

plugins/lib/ stays in the tree: it is the provider-api runtime the core loads before any provider, not a provider.

Consequences

• Providers track fast-moving vendor APIs outside the core, and every provider goes through the same install, version gate, key entry and contract.
• A fresh core offers no hosted model until a provider is installed. The Preferences Agent page shows a hint pointing at Extensions… while only echo is present.