Documentation Index
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All configuration can be provided through environment variables. Programmatic options passed to init() always take precedence.
Core identity
| Variable | Programmatic option | Description |
|---|
DD_SERVICE | service | Service name. Inferred from package.json if not set. |
DD_ENV | env | Environment name (e.g., prod, staging). |
DD_VERSION | version | Application version. Inferred from package.json if not set. |
DD_TAGS | tags | Global tags as comma-separated key:value pairs. |
Agent connectivity
| Variable | Programmatic option | Default | Description |
|---|
DD_AGENT_HOST | hostname | 127.0.0.1 | Hostname of the Datadog Agent. |
DD_TRACE_AGENT_PORT | port | 8126 | Port of the Datadog Agent. |
DD_TRACE_AGENT_URL | url | — | Full URL of the Agent. Overrides host/port. |
DD_TRACE_AGENT_PROTOCOL_VERSION | protocolVersion | 0.4 | Trace API protocol version. |
Tracing behavior
| Variable | Programmatic option | Default | Description |
|---|
DD_TRACE_ENABLED | — | true | Master switch. Set to false to disable all tracing. |
DD_APM_TRACING_ENABLED | apmTracingEnabled | true | Enable APM tracing (distinct from standalone AppSec). |
DD_TRACE_FLUSH_INTERVAL | flushInterval | 2000 | Interval (ms) between trace flushes to the Agent. |
DD_TRACE_PARTIAL_FLUSH_MIN_SPANS | flushMinSpans | 1000 | Number of spans to trigger a partial trace flush. |
DD_TRACE_REPORT_HOSTNAME | reportHostname | false | Add the hostname tag to all spans. |
DD_TRACE_STARTUP_LOGS | startupLogs | false | Print tracer configuration at startup. |
DD_TRACE_LOG_LEVEL | logLevel | debug | Log level when debug logging is enabled. |
DD_TRACE_HEADER_TAGS | headerTags | — | Comma-separated HTTP headers to capture as span tags. |
DD_SERVICE_MAPPING | serviceMapping | — | Override service names per plugin, e.g. pg:my-pg,redis:my-redis. |
DD_TRACE_SPAN_ATTRIBUTE_SCHEMA | — | v0 | Span attribute naming schema version (v0 or v1). |
DD_TRACE_PROPAGATION_STYLE | tracePropagationStyle | datadog,tracecontext | Context propagation styles (comma-separated). |
DD_TRACE_PROPAGATION_STYLE_INJECT | tracePropagationStyle.inject | — | Propagation styles for injection only. |
DD_TRACE_PROPAGATION_STYLE_EXTRACT | tracePropagationStyle.extract | — | Propagation styles for extraction only. |
DD_TRACE_OBFUSCATION_QUERY_STRING_REGEXP | — | — | Regex to obfuscate query string values in http.url tags. |
Sampling
| Variable | Programmatic option | Default | Description |
|---|
DD_TRACE_SAMPLE_RATE | sampleRate | — | Global sample rate (0–1). Defers to Agent if not set. |
DD_TRACE_RATE_LIMIT | rateLimit | — | Maximum traces per second after sampling rules. |
DD_TRACE_SAMPLING_RULES | samplingRules | [] | JSON array of sampling rules with service, name, sampleRate. |
DD_SPAN_SAMPLING_RULES | spanSamplingRules | [] | JSON array of span sampling rules for dropped traces. |
DD_SPAN_SAMPLING_RULES_FILE | spanSamplingRules | — | Path to a JSON file containing span sampling rules. |
Log injection
| Variable | Programmatic option | Default | Description |
|---|
DD_LOGS_INJECTION | logInjection | false | Inject trace IDs into log records. |
Runtime metrics
| Variable | Programmatic option | Default | Description |
|---|
DD_RUNTIME_METRICS_ENABLED | runtimeMetrics | false | Enable runtime metrics collection. |
DD_RUNTIME_METRICS_GC_ENABLED | runtimeMetrics.gc | — | Enable garbage collection metrics. |
DD_RUNTIME_METRICS_EVENT_LOOP_ENABLED | runtimeMetrics.eventLoop | — | Enable event loop lag metrics. |
DD_RUNTIME_METRICS_RUNTIME_ID_ENABLED | runtimeMetricsRuntimeId | false | Add runtime-id tag to runtime metrics. |
DD_DOGSTATSD_HOST | dogstatsd.hostname | 127.0.0.1 | DogStatsD Agent hostname for runtime metrics. |
DD_DOGSTATSD_PORT | dogstatsd.port | 8125 | DogStatsD Agent port. |
Profiling
| Variable | Programmatic option | Default | Description |
|---|
DD_PROFILING_ENABLED | profiling | false | Enable continuous profiling. |
DD_PROFILING_EXPORTERS | — | agent | Profiling data exporter. |
DD_PROFILING_SOURCE_MAP | — | true | Use source maps in profiling output. |
AppSec
| Variable | Programmatic option | Default | Description |
|---|
DD_APPSEC_ENABLED | appsec.enabled | false | Enable Application Security Monitoring. |
DD_APPSEC_RULES | appsec.rules | — | Path to a custom WAF rules JSON file. |
DD_APPSEC_TRACE_RATE_LIMIT | appsec.rateLimit | 100 | Max AppSec attack traces per second. |
DD_APPSEC_WAF_TIMEOUT | appsec.wafTimeout | 5000 | Max WAF execution time in microseconds. |
DD_APPSEC_OBFUSCATION_PARAMETER_KEY_REGEXP | appsec.obfuscatorKeyRegex | — | Regex to redact sensitive keys in attack reports. |
DD_APPSEC_OBFUSCATION_PARAMETER_VALUE_REGEXP | appsec.obfuscatorValueRegex | — | Regex to redact sensitive values in attack reports. |
DD_APPSEC_HTTP_BLOCKED_TEMPLATE_HTML | appsec.blockedTemplateHtml | — | Path to custom HTML block page template. |
DD_APPSEC_HTTP_BLOCKED_TEMPLATE_JSON | appsec.blockedTemplateJson | — | Path to custom JSON block response template. |
DD_APPSEC_AUTO_USER_INSTRUMENTATION_MODE | appsec.eventTracking.mode | identification | User tracking mode: identification, anonymous, or disabled. |
DD_APPSEC_RASP_ENABLED | appsec.rasp.enabled | false | Enable Runtime Application Self-Protection (RASP). |
DD_APPSEC_STACK_TRACE_ENABLED | appsec.stackTrace.enabled | true | Enable stack trace reporting in AppSec events. |
DD_APPSEC_MAX_STACK_TRACES | appsec.stackTrace.maxStackTraces | 2 | Maximum number of stack traces per event. |
DD_APPSEC_MAX_STACK_TRACE_DEPTH | appsec.stackTrace.maxDepth | 32 | Maximum stack frame depth per trace. |
DD_API_SECURITY_ENABLED | appsec.apiSecurity.enabled | true | Enable API Security schema collection. |
IAST
| Variable | Programmatic option | Default | Description |
|---|
DD_IAST_ENABLED | iast.enabled | false | Enable IAST vulnerability detection. |
DD_IAST_REQUEST_SAMPLING | — | 30 | Percentage of requests analyzed (0–100). |
DD_IAST_MAX_CONCURRENT_REQUESTS | — | 2 | Max requests analyzed concurrently. |
DD_IAST_REDACTION_ENABLED | — | true | Enable redaction of sensitive values in vulnerability reports. |
DD_IAST_DEDUPLICATION_ENABLED | — | true | Suppress duplicate vulnerability reports. |
Remote configuration
| Variable | Programmatic option | Default | Description |
|---|
DD_REMOTE_CONFIGURATION_ENABLED | — | true | Enable Remote Configuration. |
DD_REMOTE_CONFIG_POLL_INTERVAL_SECONDS | remoteConfig.pollInterval | 5 | Seconds between Remote Config polls. |
Data Streams and DBM
| Variable | Programmatic option | Default | Description |
|---|
DD_DATA_STREAMS_ENABLED | dsmEnabled | false | Enable Data Streams Monitoring. |
DD_DBM_PROPAGATION_MODE | dbmPropagationMode | disabled | DBM–APM link mode: disabled, service, or full. |
Client IP
| Variable | Programmatic option | Default | Description |
|---|
DD_TRACE_CLIENT_IP_ENABLED | clientIpEnabled | false | Collect client IP from request headers. |
DD_TRACE_CLIENT_IP_HEADER | clientIpHeader | — | Header name to read client IP from. |
Code origin for spans
| Variable | Programmatic option | Default | Description |
|---|
DD_CODE_ORIGIN_FOR_SPANS_ENABLED | codeOriginForSpans.enabled | true | Attach source code location to span metadata. |
Dynamic instrumentation
| Variable | Description |
|---|
DD_DYNAMIC_INSTRUMENTATION_ENABLED | Enable Dynamic Instrumentation (live debugging). |
DD_DYNAMIC_INSTRUMENTATION_PROBE_FILE | Path to a file containing probe definitions. |
DD_DYNAMIC_INSTRUMENTATION_REDACTED_IDENTIFIERS | Comma-separated variable names to redact from DI snapshots. |
LLM Observability
| Variable | Description |
|---|
DD_LLMOBS_ENABLED | Enable LLM Observability. |
DD_LLMOBS_ML_APP | ML application name for LLMObs grouping. |
DD_LLMOBS_AGENTLESS_ENABLED | Submit LLMObs data directly to the Datadog backend without an Agent. |
OpenTelemetry compatibility
The following OTel environment variables are mapped to Datadog equivalents:
| OTel variable | Datadog equivalent | Notes |
|---|
OTEL_SERVICE_NAME | DD_SERVICE | |
OTEL_RESOURCE_ATTRIBUTES | DD_TAGS | |
OTEL_TRACES_SAMPLER | DD_TRACE_SAMPLE_RATE | parentbased_traceidratio → sample rate |
OTEL_TRACES_SAMPLER_ARG | DD_TRACE_SAMPLE_RATE | Used together with OTEL_TRACES_SAMPLER |
OTEL_PROPAGATORS | DD_TRACE_PROPAGATION_STYLE | |
OTEL_LOG_LEVEL | DD_TRACE_LOG_LEVEL | |
OTEL_METRICS_EXPORTER | DD_RUNTIME_METRICS_ENABLED | none → disabled |
OTEL_SDK_DISABLED | DD_TRACE_OTEL_ENABLED | |
If both an OTel variable and its Datadog equivalent are set, the Datadog variable takes precedence and a telemetry counter is incremented to track the conflict.
Crash tracking
| Variable | Default | Description |
|---|
DD_CRASHTRACKING_ENABLED | true (non-serverless) | Enable crash tracking. Automatically disabled in serverless environments. |
Debugging
| Variable | Description |
|---|
DD_TRACE_DEBUG | Set to true to enable debug logging to stdout/stderr. |
DD_TRACE_STARTUP_LOGS | Set to true to print tracer configuration at startup. |
DD_TRACE_SPAN_LEAK_DEBUG | Enable span leak detection (values: 0, 1, 2). |
