A question buyers ask AI

What tools can help me monitor LLM agents in production for failures, latency spikes, and runaway costs across multi-step tool calls?

Measured in 1 answer, last on Nov 8, 2026. Only the passages that name a brand are shown.

Brands in the answers

BrandNamed inRecommended inPositiveAvg. position
Langfuse100%100%100%1
LangSmith100%100%100%2
Arize Phoenix100%100%100%3
Braintrust100%100%100%5
Portkey100%100%100%6
OpenTelemetry100%100%100%—
Datadog100%100%100%—
OpenLLMetry100%0%0%—
Galileo100%0%0%—
Pydantic Logfire100%0%0%—
OpenInference100%0%0%—
New Relic100%0%0%—
Comet Opik100%0%0%—
Weights & Biases Weave100%0%0%—

Where each answer names a brand

Answer 1 · Nov 8, 2026 · 12 sources cited
Langfuse#1RecommendedSite citedpositive
“I'd start with Langfuse + OpenTelemetry and add Datadog if you need deeper infrastructure monitoring.”
+ open-source option

“Best open-source option”

+ distributed traces across LLM calls and tool invocations

“Distributed traces across LLM calls and tool invocations.”

+ token usage and cost attribution

“Token usage and cost attribution.”

+ latency breakdowns and error tracking

“Latency breakdowns and error tracking.”

+ prompt versioning and evaluation

“Prompt versioning and evaluation.”

+ self-hosting

“Self-hosting available.”

+ control over telemetry and infrastructure

“Particularly good if you want control over telemetry and infrastructure.”

LangSmith#2Recommendedpositive
“Best for debugging agent workflows”
+ debugging agent workflows

“Best for debugging agent workflows”

+ visualizes complete agent execution trees

“Visualizes complete agent execution trees.”

+ shows tool calls, model calls, and retries

“Shows individual tool calls, model calls, and retries.”

+ tracks latency and token consumption

“Tracks latency and token consumption.”

+ production evaluation and failure analysis

“Supports production evaluation and failure analysis.”

+ identifies recurring failure patterns

“Helps identify recurring failure patterns.”

+ LangChain and LangGraph support

“Especially useful for LangChain and LangGraph applications, but also supports other frameworks.”

Arize Phoenix#3RecommendedSite citedpositive
“A strong choice for framework-independent monitoring and diagnosing complex agent behavior.”
+ latency and token analysis

“Latency and token analysis.”

+ tracing and evaluations

“Best for tracing and evaluations”

+ OpenTelemetry-based tracing

“OpenTelemetry-based tracing.”

+ tool-call and retrieval tracing

“Tool-call and retrieval tracing.”

+ LLM evaluation and quality monitoring

“LLM evaluation and quality monitoring.”

+ open-source deployment

“Open-source deployment.”

+ framework-independent monitoring

“A strong choice for framework-independent monitoring and diagnosing complex agent behavior.”

Braintrust#5RecommendedSite citedpositive
“Best for quality regression detection”
+ quality regression detection

“Best for quality regression detection”

+ production traces and debugging

“Production traces and debugging.”

+ automated evaluation of agent outputs

“Automated evaluation of agent outputs.”

+ regression detection

“Regression detection.”

+ dataset-based testing

“Dataset-based testing.”

+ evaluation-driven development workflows

“Evaluation-driven development workflows.”

+ detecting incorrect results

“Particularly valuable when an agent technically succeeds but produces incorrect results.”

Portkey#6Recommendedpositive
“Best for cost and request governance”
+ cost and request governance

“Best for cost and request governance”

+ centralized LLM request logging

“Centralized LLM request logging.”

+ token and cost tracking

“Token and cost tracking.”

+ provider-level latency monitoring

“Provider-level latency monitoring.”

+ automatic retries and fallbacks

“Automatic retries and fallbacks.”

+ routing and guardrails

“Routing and guardrails.”

OpenLLMetry
“OpenLLMetry: Instrumentation for LLM applications.”
OpenTelemetryRecommendedpositive
“I'd strongly recommend standardizing your instrumentation around OpenTelemetry (OTel).”
+ vendor-independent instrumentation

“It allows you to instrument your agents independently of the observability vendor.”

+ distributed traces, metrics and logs

“OpenTelemetry: Distributed traces, metrics and logs.”

“the comparison of 2026 platforms also includes Opik, W&B Weave, Galileo and Pydantic Logfire.”
“the comparison of 2026 platforms also includes Opik, W&B Weave, Galileo and Pydantic Logfire.”
OpenInferenceSite cited
“OpenInference: AI-specific tracing conventions maintained by Arize.”
DatadogRecommendedSite citedpositive
“rather than relying exclusively on traditional APM tools like Datadog or New Relic”
+ enterprise operations

“Best for enterprise operations”

+ correlates LLM traces with application traces

“Correlates LLM traces with application traces.”

+ infrastructure and service latency monitoring

“Monitors infrastructure and service latency.”

+ model usage and cost tracking

“Tracks model usage and costs.”

+ alerting and incident management

“Supports alerting and incident management.”

+ connects agent failures to infrastructure problems

“Helps connect agent failures to infrastructure problems.”

“rather than relying exclusively on traditional APM tools like Datadog or New Relic”
“the comparison of 2026 platforms also includes Opik, W&B Weave, Galileo and Pydantic Logfire.”
“the comparison of 2026 platforms also includes Opik, W&B Weave, Galileo and Pydantic Logfire.”

Sources the answers cite

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