Makes the ProviderErrorRule `scope` field real at the persistence layer, exclusively for agentrouter (owner decision; every other provider keeps byte-identical behavior).
checkFallbackError now surfaces `ruleScope` behind the HONORS_RULE_LOCK_SCOPE_PROVIDERS allowlist, and the agentrouter 403 path consults the rules before the generic apikey-FORBIDDEN early-return. markAccountUnavailable honors scope "connection" with a temporary connection cooldown instead of a per-model lockout — guarded so a permanent state can never be downgraded to a transient retry loop — and combo now skips the exhausted account within the same request, which also stops force-reusing the just-cooled connection via allowRateLimitedConnection.
Documented in RESILIENCE_GUIDE §7 with the honest limits (disableCooling connections keep per-model behavior; the 6h model-access cooldown is clamped by mlSettings.maxCooldownMs, 30min by default; same-request skip needs targets carrying their own connectionId).
Closes#10334
agentrouter.org signals temporary quota exhaustion with HTTP 403/400 and a Chinese body (用户额度不足) instead of 429, so clients like Claude Code treat it as permanent and abort, and the fallback engine classified it as a generic apikey AUTH_ERROR.
New registry open-sse/config/upstreamStatusRestatement.ts restates those statuses to 429 with a synthetic Retry-After at a single hook in chatCore's providerFailure block (after parseUpstreamError), so classification, combo aggregation and the client response all see a retryable error. 无权访问模型 (permanently no model access) is veto-listed and never restated.
agentrouter classification rules are registered in providerErrorRules.ts and reach the real checkFallbackError path through resolveRuleMatchBody() with an exclusive FULL_TEXT_RULE_PROVIDERS allowlist — every other provider keeps its previous behavior byte-for-byte.
Known limitations tracked in #10334: the rules' scope field is informational (persistence applies per-model lockout for agentrouter), the 403-only model-access rule has no production path yet, and errors embedded in 200 SSE streams are not restated.
Refs #10334
