Python: OTLP HTTP exporter sends to bare base endpoint instead of /v1/{signal} path

[droideronline]

Bug Report

Summary

When configuring OpenTelemetry export via OTEL_EXPORTER_OTLP_ENDPOINT with an HTTP protocol (http/protobuf or http), traces, metrics, and logs are sent to the bare base URL (e.g. http://localhost:4318) instead of the correct signal-specific paths (http://localhost:4318/v1/traces, /v1/metrics, /v1/logs).

Affected Component

python/packages/core/agent_framework/observability.py — _get_exporters_from_env()

Root Cause

Per the OpenTelemetry specification, OTEL_EXPORTER_OTLP_ENDPOINT is a base URL for HTTP transport — the SDK automatically appends /v1/traces, /v1/metrics, or /v1/logs when it reads the env var directly. Signal-specific env vars (OTEL_EXPORTER_OTLP_TRACES_ENDPOINT, etc.) are full URLs used verbatim.

_get_exporters_from_env was reading the base endpoint and forwarding it directly as the endpoint= constructor argument to the exporter. The OTel SDK always treats a programmatically-provided endpoint= argument as a full URL (no auto-append). This meant the /v1/{signal} path was silently dropped.

Reproduction

import os
os.environ["OTEL_EXPORTER_OTLP_ENDPOINT"] = "http://localhost:4318"
os.environ["OTEL_EXPORTER_OTLP_PROTOCOL"] = "http/protobuf"

# Exporters will attempt to POST to http://localhost:4318
# instead of http://localhost:4318/v1/traces (etc.)
configure_azure_monitor(...)  # or enable_telemetry(...)

With a collector listening on http://localhost:4318, no spans/metrics/logs are received because the POST goes to the wrong path and returns 404.

Expected Behavior

With OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4318 and OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf:

• Traces exporter → http://localhost:4318/v1/traces
• Metrics exporter → http://localhost:4318/v1/metrics
• Logs exporter → http://localhost:4318/v1/logs

Signal-specific env vars (e.g. OTEL_EXPORTER_OTLP_TRACES_ENDPOINT) continue to be used verbatim (no path appended).

gRPC behavior is unchanged — the base endpoint is used as-is for gRPC.

Fix

Replicate the OTel spec's auto-append logic inside _get_exporters_from_env when falling back to the base endpoint under HTTP protocol. See the linked PR for the change and added test coverage.