Update schema comment to match actual code default [400, 429, 503, 529].
Previously the comment omitted 400 which is included in the code default.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Bug fixes:
1. extractStatusCode: handle nested data.statusCode (Anthropic error structure)
2. Error regex: relax credit.*balance.*too.*low pattern for multi-char gaps
3. Zod schema: bump max_fallback_attempts from 10 to 20 (config rejected silently)
4. getFallbackModelsForSession: fallback to sisyphus/any agent when session.error lacks agent
5. Model detection: derive model from agent config when session.error lacks model info
6. Auto-retry: resend last user message with fallback model via promptAsync
7. Persistent fallback: override model on every chat.message (not just pendingFallbackModel)
8. Manual model change: detect UI model changes and reset fallback state
9. Agent preservation: include agent in promptAsync body to prevent defaulting to sisyphus
Additional:
- Add sessionRetryInFlight guard to prevent double-retries
- Add resolveAgentForSession with 3-tier resolution (event → session memory → session ID)
- Add normalizeAgentName for display names like "Prometheus (Planner)" → "prometheus"
- Add resolveAgentForSessionFromContext to fetch agent from session messages
- Move AGENT_NAMES and agentPattern to module scope for reuse
- Register runtime-fallback hooks in event.ts and chat-message.ts
- Remove diagnostic debug logging from isRetryableError
- Add 400 to default retry_on_errors and credit/balance patterns to RETRYABLE_ERROR_PATTERNS
Add configuration schemas for runtime model fallback feature:
- RuntimeFallbackConfigSchema with enabled, retry_on_errors,
max_fallback_attempts, cooldown_seconds, notify_on_fallback
- FallbackModelsSchema for init-time fallback model selection
- Add fallback_models to AgentOverrideConfigSchema and CategoryConfigSchema
- Export types and schemas from config/index.ts
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>