glean-observability

# Glean Observability ## Overview Glean aggregates enterprise knowledge across dozens of connectors, making indexing health and search quality the two pillars of observability. Monitor connector sync status to catch stale content before users notice, track search latency to maintain sub-second responses, and measure zero-result rates to identify coverage gaps. Degraded indexing silently erodes search relevance, so proactive alerting is essential. ## Key Metrics | Metric | Type | Target | Alert Threshold | |--------|------|--------|-----------------| | Search latency p95 | Histogram | < 400ms | > 1s | | Zero-result query rate | Gauge | < 5% | > 10% | | Documents indexed per run | Counter | Stable +/-5% | Drop > 20% | | Connector sync errors | Counter | 0 | > 3 per hour | | Stale content ratio | Gauge | < 10% | > 25% (>30 days old) | | Indexing throughput | Gauge | > 1000 docs/min | < 500 docs/min | ## Instrumentation ```typescript async function trackGleanSearch(query: string, client: GleanClient) { const start = Date.now(); try { const results = await client.search({ query }); const latency = Date.now() - start; metrics.histogram('glean.search.latency', latency); metrics.increment('glean.search.total'); if (results.totalCount === 0) metrics.increment('glean.search.zero_results'); return results; } catch (err) { metrics.increment('glean.search.errors', { error: err.code }); throw err; } } ``` ## Health Check Dashboard ```typescri...