In depth
Brain fallback is what saves your Saturday afternoon when an Anthropic balance hits zero. The YAML declares a primary brain and a fallback brain, the runtime watches for 402, 429, and 'insufficient credit' errors and silently swaps to the fallback for the next turn. The agent keeps running, the user does not notice. Next turn retries the primary first, so you do not stay on the fallback longer than needed.
What it looks like in practice
YAML
1brain:2 provider: anthropic3 model: claude-sonnet-4-64 fallback:5 provider: deepseek6 model: deepseek-chatRelated concepts
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Engineering notes from the Digitorn team. No marketing, no launch announcements, no "10 prompts that will change your life". Just the things we write that we'd want to read.