The file no longer contains any fallback/handoff logic after the Athena
NLP removal — only generic terminal-event helpers (isTerminalFinishValue,
isTerminalStepFinishPart). Name now matches content.
The fallback scanned Athena's message text for natural-language handoff
phrases ("switching to Atlas", etc.) and synthetically created a pending
switch when the switch_agent tool wasn't called. In practice this path
never fired in real sessions — Athena always correctly called the tool.
Removes ~135 lines of Athena-coupled code, keeping the generic
switch_agent → apply path fully intact.
Fixes from multi-model council audit (7 members, 19 findings, 9 selected):
- Use parseModelString() for cross-provider Anthropic thinking config (#3)
- Update stale AGENTS.md athena directory listing (#4)
- Replace prompt in appendMissingCouncilPrompt instead of appending (#5)
- Extract duplicated session cleanup logic in agent-switch hook (#6)
- Surface skipped council members when >=2 valid members exist (#9)
- Expand fallback handoff regex with negation guards (#11)
- Remove dead council-member agent from agentSources and tests (#12)
- Make runtime council member duplicate check case-insensitive (#14)
- Fix false-positive schema tests by adding required name field (#18)
processedFallbackMessages was only cleaned up on session.deleted, not session.error. This could leak memory for errored sessions. Mirrors the existing session.deleted cleanup pattern.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Delete marker from processedFallbackMessages on failure so message can be retried. Add MAX_PROCESSED_FALLBACK_MARKERS=500 with eviction to prevent unbounded Set growth.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
