Today if gemini-3.1-pro hits Cursor's "Provider Error" (transient backend outage), that reviewer slot just fails — the human has to notice and manually swap in another model.
Proposed shape
Let each roster slot carry an optional fallback list. Either in SKILL.md's default roster:
```md
Default roster when no models are specified:
- Claude — via the
code-reviewer agent. (no fallback; core requirement)
gpt-5.2 — via Cursor. Fallbacks: gpt-5.4-high, gpt-5.5-highgemini-3.1-pro — via Cursor. Fallbacks: gemini-3-flash, grok-4-20-thinking, composer-2
```
Or in ~/.config/crew/config.toml:
```toml
[[roster]]
name = "gemini-3.1-pro"
fallbacks = ["gemini-3-flash", "grok-4-20-thinking", "composer-2"]
```
When a slot's primary errors, walk its fallback list until one succeeds or the list is exhausted. Prefer different families (preserve the "three different families" property — don't fall back to a second Anthropic reviewer since the Claude leg already covers that).
Failure-classification prerequisite
The wrapper needs to distinguish:
- exit 2: MODEL_NOT_AVAILABLE (permanent — walk immediately)
- exit 3: PROVIDER_ERROR (transient — retry once with backoff, then walk)
- exit 1: generic (walk)
Today each backend script just returns exit 1 for both flavors.
Applies to
/crew:review roster (per-slot fallback chain)/crew:market roster (if a candidate's backend fails, spawn a fallback in its slot rather than losing the diversity)
Originally flagged in PR #61's follow-ups list.
Today if
gemini-3.1-prohits Cursor's "Provider Error" (transient backend outage), that reviewer slot just fails — the human has to notice and manually swap in another model.Proposed shape
Let each roster slot carry an optional fallback list. Either in
SKILL.md's default roster:```md
Default roster when no models are specified:
code-revieweragent. (no fallback; core requirement)gpt-5.2— via Cursor. Fallbacks:gpt-5.4-high,gpt-5.5-highgemini-3.1-pro— via Cursor. Fallbacks:gemini-3-flash,grok-4-20-thinking,composer-2```
Or in
~/.config/crew/config.toml:```toml
[[roster]]
name = "gemini-3.1-pro"
fallbacks = ["gemini-3-flash", "grok-4-20-thinking", "composer-2"]
```
When a slot's primary errors, walk its fallback list until one succeeds or the list is exhausted. Prefer different families (preserve the "three different families" property — don't fall back to a second Anthropic reviewer since the Claude leg already covers that).
Failure-classification prerequisite
The wrapper needs to distinguish:
Today each backend script just returns exit 1 for both flavors.
Applies to
/crew:reviewroster (per-slot fallback chain)/crew:marketroster (if a candidate's backend fails, spawn a fallback in its slot rather than losing the diversity)Originally flagged in PR #61's follow-ups list.