Opentelemetry

OpenTelemetry SDKs expose a programmatic API for creating spans, recording metrics, and emitting log records. The OTel Collector accepts OTLP (gRPC port 4317, HTTP port 4318) and can be configured to filter, batch, and export to multiple backends. The Collector configuration is YAML-based with a REST endpoint for live config in newer versions. SDK API is stable (trace and metric APIs are GA; logs API is RC). Protocol is OTLP over gRPC or HTTP. No REST query API — that's the backend's responsibility (Jaeger, Prometheus, etc.).

OTel SDKs handle batch export with configurable retry logic, timeout, and backpressure. The Collector has retry, queue, and memory limiter processors. Span export failures are non-blocking by default — applications continue running if telemetry export fails. Error codes are surfaced via SDK logs, not application errors. The Collector is designed for high-throughput, high-reliability operation. SDK stability varies by language; Python and Go are most mature.

OpenTelemetry (OTel) is the CNCF standard for distributed observability. It provides language SDKs (Python, Go, JS, Java, etc.) for instrumenting code with traces, metrics, and logs, plus the OTel Collector for receiving, processing, and exporting telemetry to any backend. Agent relevance is high for agents monitoring distributed systems or building observability pipelines: the Collector exposes gRPC/HTTP endpoints for OTLP ingestion, and the SDK auto-instruments common frameworks. OTel itself has no SaaS billing — it's infrastructure. The Collector can be deployed as a sidecar or gateway. Confidence is docs-derived; runtime behavior varies by backend and SDK version.

OTel itself has no authentication surface — security is delegated to the Collector and backend. The Collector supports TLS for OTLP endpoints and header-based auth for exporters. SDK-level auth uses exporter configuration (headers, API keys for cloud backends). No shared secret or API key for OTel itself. Production deployments should use mTLS between SDK and Collector.

Documentation at opentelemetry.io is comprehensive but sprawling across multiple repos and language-specific guides. Getting started guides exist for major languages. The Collector documentation covers all processors, exporters, and receivers. Community support via CNCF Slack and GitHub. SDK-specific documentation quality varies: Go and Java are strong, others less so. The specification is detailed and vendor-neutral. High information density; requires time investment to navigate.