The Blind Spots in Traditional Monitoring
Your LLM application is live. Requests are flowing, latency is acceptable, and error rates are low. Yet users complain about "unhelpful responses," support tickets pile up with edge cases you never tested, and nobody can explain why model behavior changed after last week's deployment.
Traditional monitoring—uptime checks, latency percentiles, error rates—tells you that your system is running, but not how well it's performing its actual job: generating useful, accurate, safe responses.
This gap between "system health" and "output quality" is where production LLM applications fail silently. You need evaluation telemetry: continuous capture and scoring of actual model inputs, outputs, and decisions in real time.
What Makes LLM Monitoring Different
1. Non-Deterministic Outputs
Unlike traditional software where add(2, 3)
always returns 5
, an LLM given the same prompt can produce different responses. Temperature settings, model updates, and sampling introduce variability. You can't rely on exact output matching—you need semantic similarity scoring, policy compliance checks, and statistical drift detection.
2. Silent Degradation
A 500 error is obvious. A model that starts responding with less helpful answers, slowly drifts toward verbose outputs, or begins hallucinating more frequently? That's invisible to traditional metrics. By the time users complain, you've already shipped thousands of poor responses.
3. Latent Quality Issues
Sometimes a response looks correct but contains subtle errors: wrong calculations embedded in natural language, outdated information presented confidently, or advice that violates company policies. Traditional monitoring has no mechanism to catch these.
4. Context Collapse
LLM applications often chain multiple calls: retrieval, reasoning, summarization. If the first step in a RAG pipeline retrieves irrelevant documents, the final response will be wrong—but latency and error rates remain normal. You need per-step telemetry to trace quality degradation through the pipeline.
The Five Pillars of Production LLM Monitoring
Pillar 1: Request-Level Telemetry Capture
Every LLM interaction should generate a trace—a structured record containing:
- Input context: User prompt, retrieved documents, conversation history
- Model metadata: Provider, model version, temperature, max tokens
- Output: Full response text, token counts, finish reason
- Timing: Per-step latency, queuing time, total duration
- Metadata: User ID, session ID, feature flags, A/B test group
Capture this at the edge, not in logs. Logs are unstructured and hard to query. Traces are first-class objects you can filter, aggregate, and score.
Example with EvalOps SDK:
from evalops import EvalOps
evalops = EvalOps(workspace="production")
@evalops.trace(scenario="customer-support-qa")
async def handle_support_query(ticket_id: str, user_query: str):
# Automatic trace capture with context
docs = await retrieve_relevant_docs(user_query)
response = await openai.chat.completions.create(
model="gpt-4",
messages=[
{"role": "system", "content": "You are a helpful support agent."},
{"role": "user", "content": f"Context: {docs}\n\nQuestion: {user_query}"}
]
)
return response.choices[0].message.content
Every call to handle_support_query
becomes a trace in EvalOps, tagged with scenario, ticket ID, and full input/output.
Pillar 2: Real-Time Quality Scoring
Once you have traces, apply scorecards—collections of metrics that evaluate response quality:
- Hallucination detection: Does the response reference facts not in the retrieved documents?
- Policy compliance: Does it avoid prohibited topics (medical advice, legal counsel, etc.)?
- Relevance: How well does it answer the user's question?
- Conciseness: Is it within acceptable length bounds?
- Toxicity: Does it contain offensive language?
- Cost efficiency: Token usage vs. quality tradeoff
These run asynchronously so they don't block user responses, but alert you within minutes if quality degrades.
Example scorecard:
scorecard:
name: production-support-qa
metrics:
- name: answer_relevance
type: llm_judge
prompt: "Rate how well this response answers the user's question (0-10)"
- name: uses_retrieved_context
type: custom
function: check_context_grounding
- name: no_medical_advice
type: policy
rules:
- deny: ["diagnose", "prescribe", "medical condition"]
- name: response_latency_p95
type: performance
threshold: 3000ms
- name: cost_per_interaction
type: budget
threshold: $0.05
EvalOps runs these metrics on every trace. If answer_relevance
drops below 7/10 for more than 5% of traces in a 15-minute window, you get alerted.
Pillar 3: Drift Detection
Models change. Providers silently update backends. Your prompt templates evolve. User behavior shifts. All of these introduce drift—changes in output distribution that may degrade quality.
Monitor:
- Token usage drift: Sudden increase suggests verbose responses or prompt bloat
- Latency drift: Provider throttling or model changes
- Semantic drift: Responses becoming more/less formal, more/less technical
- Score distribution drift: Hallucination rates creeping up, policy violations increasing
Statistical tests like Kolmogorov-Smirnov or Jensen-Shannon divergence can detect when current traces diverge from baseline distributions.
Example alert rule:
alert:
name: hallucination-drift
condition: |
current_week.hallucination_score.mean > baseline.hallucination_score.p95
window: 7d
notify: ["#ai-incidents", "on-call@company.com"]
Pillar 4: Trace Sampling and Inspection
You can't manually review every trace, but you need visibility into outliers:
- Worst performers: Lowest scoring traces by any metric
- Edge cases: Rare input patterns or unusual outputs
- User escalations: Traces linked to support tickets or negative feedback
- A/B test comparisons: Side-by-side for variant analysis
Example query in EvalOps:
SELECT * FROM traces
WHERE scenario = "customer-support-qa"
AND answer_relevance < 5
AND timestamp > NOW() - INTERVAL 24 HOURS
ORDER BY timestamp DESC
LIMIT 50
This surfaces the 50 worst responses in the last day. You can replay them, annotate why they failed, and add them to regression test suites.
Pillar 5: Feedback Loop Integration
Production monitoring isn't complete without user signals:
- Thumbs up/down: Explicit feedback on responses
- Copy-paste rate: Users copying responses indicates usefulness
- Clarification requests: User immediately asking follow-up questions suggests initial response was unclear
- Session abandonment: User leaves without completing task
- Support escalation: User submits ticket after interacting with AI
Correlate these with trace IDs to ground abstract metrics in real user experience.
Example integration:
@app.post("/feedback")
async def record_feedback(trace_id: str, rating: int, comment: str):
evalops.add_feedback(
trace_id=trace_id,
rating=rating,
comment=comment,
source="user_explicit"
)
Now you can filter traces by rating < 3
to see exactly what users disliked, and retrain scorecards to predict user satisfaction.
Building a Production Monitoring Dashboard
Your dashboard should answer:
Is the system healthy right now?
- Request volume, error rate, P95 latency
- Recent deployments or config changes
Is quality degrading?
- Score trends over time (hallucination, relevance, policy violations)
- Drift alerts and anomaly detection
What are the worst failures?
- Bottom 1% of traces by score
- User-reported issues with linked traces
How do variants compare?
- A/B test results (prompt changes, model switches)
- Cost vs. quality tradeoffs
Example EvalOps dashboard layout:
dashboard:
- section: Health
widgets:
- type: timeseries
metric: request_rate
- type: number
metric: error_rate
threshold: 0.01
- section: Quality
widgets:
- type: timeseries
metrics:
- answer_relevance
- hallucination_score
- policy_violation_rate
- type: distribution
metric: response_length_tokens
- section: Cost
widgets:
- type: number
metric: daily_spend
- type: scatter
x: tokens_used
y: answer_relevance
- section: Failures
widgets:
- type: table
query: "SELECT * FROM traces WHERE answer_relevance < 5 ORDER BY timestamp DESC LIMIT 20"
Alerting Strategies
Not every dip in quality deserves a page. Configure multi-tier alerting:
Tier 1: Critical (Page Immediately)
- Error rate > 5% for 5 minutes
- Policy violation rate > 1% for 10 minutes (e.g., leaked PII)
- Complete service outage
Tier 2: Warning (Slack/Email)
- P95 latency > 3s for 15 minutes
- Hallucination rate > 10% for 30 minutes
- Token cost exceeds daily budget by 20%
Tier 3: Info (Weekly Summary)
- Gradual semantic drift detected
- User satisfaction scores trending down
- Model usage patterns changing
Example PagerDuty integration:
alerts:
- name: critical-policy-violation
severity: critical
condition: policy_violation_rate > 0.01
window: 10m
integrations:
- pagerduty
- slack_channel: "#ai-incidents"
- name: quality-degradation
severity: warning
condition: answer_relevance.p50 < 7 AND trend = "decreasing"
window: 30m
integrations:
- slack_channel: "#ai-monitoring"
Case Study: Detecting a Silent Regression
Scenario: A customer service chatbot using GPT-4 through Azure OpenAI. The team deployed a new prompt template to make responses more concise.
What traditional monitoring showed:
- Latency improved (shorter responses = faster generation)
- Error rate unchanged
- Request volume normal
What evaluation telemetry revealed:
answer_relevance
scores dropped from 8.2 to 6.5 averagecontains_resolution_steps
metric (custom boolean) dropped from 92% to 64%- User feedback ratings dropped from 4.1 to 3.2 stars
- Support ticket escalation rate increased 18%
Root cause: The new prompt's emphasis on conciseness caused the model to omit critical troubleshooting steps. Technically correct, but not actionable for users.
Resolution: Reverted prompt, added a includes_actionable_steps
metric to the scorecard, and now test all prompt changes against a benchmark set before deploying.
Traditional monitoring would have missed this entirely. Users would have suffered for weeks until manual review caught the pattern.
Anti-Patterns to Avoid
1. Monitoring Only Aggregates
Averages hide problems. A 95% success rate means 1 in 20 users get a bad experience—that's thousands of failures per day at scale. Track percentiles (P50, P95, P99) and worst performers, not just means.
2. Manual Spot-Checking
Reviewing 10 random traces weekly doesn't catch rare edge cases or gradual drift. Automate scoring and alerting. Reserve human review for investigating alerts and annotating failure modes.
3. Over-Indexing on User Feedback
Most users don't leave feedback. Vocal minorities skew ratings. You need instrumentation-based metrics (hallucination detection, policy compliance) that run on 100% of traces, supplemented by user signals.
4. Ignoring Cost
Quality isn't free. A model that scores 9/10 but costs $0.50 per interaction isn't sustainable. Monitor cost-adjusted quality: quality_score / cost_per_response
and optimize for this ratio.
5. No Rollback Plan
If you detect a regression, can you roll back immediately? Have blue/green deployments for prompts and models, with automated rollback triggers when quality thresholds breach.
Implementing Production Monitoring: A Checklist
- Instrument all LLM calls with trace capture
- Define scorecards for each scenario (support, content generation, code completion, etc.)
- Set up async scoring pipeline (don't block user responses)
- Create dashboards for health, quality, cost
- Configure alerting (critical, warning, info)
- Integrate user feedback signals
- Establish baseline metrics for drift detection
- Document runbooks for common alert scenarios
- Schedule weekly trace reviews with product team
- Automate regression test runs on prompt/model changes
Tooling Recommendations
- Trace capture: EvalOps SDK, Grimoire CLI, LangSmith, Weights & Biases
- Quality scoring: EvalOps Scorecards, custom metrics, LLM-as-judge
- Alerting: PagerDuty, Opsgenie, Slack webhooks
- Dashboards: EvalOps Studio, Grafana, Datadog
- Drift detection: Statistical tests (KS, JS divergence), EvalOps built-in monitors
Conclusion
Production LLM monitoring is evaluation at scale. You're running the same quality assessments you do during development—hallucination detection, relevance scoring, policy compliance—but continuously, on every real user interaction.
This visibility transforms how you ship AI. Instead of deploying and hoping, you deploy with confidence intervals: "This prompt change improves relevance by 12% with 95% confidence, costs 8% more, and introduces no new policy violations."
Start simple:
- Capture traces for your highest-volume scenario
- Define 3-5 core quality metrics
- Set up a dashboard and one critical alert
- Review the worst traces weekly
Then expand: more scenarios, richer metrics, tighter feedback loops. Within months, you'll have the same operational confidence in your LLM application that you have in traditional software.
And when something breaks—because it will—you'll know immediately, understand why, and have the data to fix it.
Next Steps:
- Install the EvalOps SDK and capture your first production trace
- Import a production monitoring Spellbook for pre-built scorecards
- Read our guide on custom metrics to score domain-specific quality
Questions? Join the EvalOps community or book a demo to see production monitoring in action.