[TEEP-4568] [AGENT-15468] fix(python): restore check_name tag on datadog.agent.check_ready

[ArmentaRoberto]

What changed

• Fixes a regression where datadog.agent.check_ready was emitted without a check_name tag value.

• Ensures the name used for reportPy3Warnings() is the successfully loaded module name, with a fallback to config.Name.

Why

• Between 7.72 and 7.73, a scoping/flow change caused the value passed to reportPy3Warnings() to be empty in some cases, resulting in missing check_name tag values and collapsing linted-state tracking.

How

• Track the successfully loaded module name (loadedName) at the get_class(...) success point.

• Use loadedName when calling reportPy3Warnings().

• Fallback to config.Name if loadedName is unexpectedly empty.

Testing / QA plan

• Repro on an affected Agent build where datadog.agent.check_ready is present but lacks check_name.

• Run Agent with a Python check that triggers the reportPy3Warnings() path.

• Verify in Metrics Explorer that datadog.agent.check_ready includes check_name:<expected>.

[agent-platform-auto-pr]

Static quality checks

✅ Please find below the results from static quality gates
Comparison made with ancestor 681899c
📊 Static Quality Gates Dashboard

31 successful checks with minimal change (< 2 KiB)

	Quality gate	Current Size
✅	agent_deb_amd64	748.049 MiB
✅	agent_deb_amd64_fips	708.157 MiB
✅	agent_heroku_amd64	325.593 MiB
✅	agent_msi	659.741 MiB
✅	agent_rpm_amd64	748.033 MiB
✅	agent_rpm_amd64_fips	708.141 MiB
✅	agent_rpm_arm64	727.128 MiB
✅	agent_rpm_arm64_fips	689.721 MiB
✅	agent_suse_amd64	748.033 MiB
✅	agent_suse_amd64_fips	708.141 MiB
✅	agent_suse_arm64	727.128 MiB
✅	agent_suse_arm64_fips	689.721 MiB
✅	docker_agent_amd64	810.525 MiB
✅	docker_agent_arm64	814.215 MiB
✅	docker_agent_jmx_amd64	1001.403 MiB
✅	docker_agent_jmx_arm64	993.813 MiB
✅	docker_cluster_agent_amd64	180.824 MiB
✅	docker_cluster_agent_arm64	196.669 MiB
✅	docker_cws_instrumentation_amd64	7.135 MiB
✅	docker_cws_instrumentation_arm64	6.689 MiB
✅	docker_dogstatsd_amd64	38.414 MiB
✅	docker_dogstatsd_arm64	36.749 MiB
✅	dogstatsd_deb_amd64	29.630 MiB
✅	dogstatsd_deb_arm64	27.802 MiB
✅	dogstatsd_rpm_amd64	29.630 MiB
✅	dogstatsd_suse_amd64	29.630 MiB
✅	iot_agent_deb_amd64	42.751 MiB
✅	iot_agent_deb_arm64	39.872 MiB
✅	iot_agent_deb_armhf	40.442 MiB
✅	iot_agent_rpm_amd64	42.751 MiB
✅	iot_agent_suse_amd64	42.751 MiB

On-wire sizes (compressed)

	Quality gate	Change	Size (prev → curr → max)
✅	agent_deb_amd64	+12.55 KiB (0.01% increase)	182.840 → 182.852 → 184.810
✅	agent_deb_amd64_fips	+11.39 KiB (0.01% increase)	174.303 → 174.314 → 177.560
✅	agent_heroku_amd64	-3.56 KiB (0.00% reduction)	87.291 → 87.287 → 88.450
✅	agent_msi	-36.0 KiB (0.02% reduction)	142.449 → 142.414 → 143.300
✅	agent_rpm_amd64	+3.35 KiB (0.00% increase)	185.778 → 185.782 → 188.160
✅	agent_rpm_amd64_fips	-40.4 KiB (0.02% reduction)	176.739 → 176.699 → 178.900
✅	agent_rpm_arm64	-16.98 KiB (0.01% reduction)	168.388 → 168.371 → 169.930
✅	agent_rpm_arm64_fips	+4.7 KiB (0.00% increase)	160.788 → 160.793 → 163.120
✅	agent_suse_amd64	+3.35 KiB (0.00% increase)	185.778 → 185.782 → 188.160
✅	agent_suse_amd64_fips	-40.4 KiB (0.02% reduction)	176.739 → 176.699 → 178.900
✅	agent_suse_arm64	-16.98 KiB (0.01% reduction)	168.388 → 168.371 → 169.930
✅	agent_suse_arm64_fips	+4.7 KiB (0.00% increase)	160.788 → 160.793 → 163.120
✅	docker_agent_amd64	neutral	275.087 MiB → 277.400
✅	docker_agent_arm64	neutral	262.678 MiB → 266.040
✅	docker_agent_jmx_amd64	neutral	343.720 MiB → 346.020
✅	docker_agent_jmx_arm64	+9.97 KiB (0.00% increase)	327.294 → 327.304 → 330.660
✅	docker_cluster_agent_amd64	neutral	63.874 MiB → 64.510
✅	docker_cluster_agent_arm64	neutral	60.136 MiB → 61.170
✅	docker_cws_instrumentation_amd64	neutral	2.994 MiB → 3.330
✅	docker_cws_instrumentation_arm64	neutral	2.726 MiB → 3.090
✅	docker_dogstatsd_amd64	neutral	14.863 MiB → 15.820
✅	docker_dogstatsd_arm64	neutral	14.202 MiB → 14.830
✅	dogstatsd_deb_amd64	neutral	7.831 MiB → 8.790
✅	dogstatsd_deb_arm64	neutral	6.718 MiB → 7.710
✅	dogstatsd_rpm_amd64	neutral	7.844 MiB → 8.800
✅	dogstatsd_suse_amd64	neutral	7.844 MiB → 8.800
✅	iot_agent_deb_amd64	neutral	11.211 MiB → 12.040
✅	iot_agent_deb_arm64	neutral	9.583 MiB → 10.450
✅	iot_agent_deb_armhf	neutral	9.779 MiB → 10.620
✅	iot_agent_rpm_amd64	neutral	11.231 MiB → 12.060
✅	iot_agent_suse_amd64	neutral	11.231 MiB → 12.060

[cit-pr-commenter-54b7da]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: 0d8c68a9-afed-4cff-a8c1-878ef1d75608

Baseline: 681899c
Comparison: 58f9a44
Diff

Optimization Goals: ✅ Improvement(s) detected

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
✅	tcp_syslog_to_blackhole	ingress throughput	+37.22	[+37.11, +37.34]	1	Logs
✅	quality_gate_logs	% cpu utilization	-50.33	[-51.68, -48.98]	1	Logs bounds checks dashboard

Experiments ignored for regressions

Regressions in experiments with settings containing erratic: true are ignored.

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	docker_containers_cpu	% cpu utilization	-2.68	[-5.68, +0.32]	1	Logs

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
✅	tcp_syslog_to_blackhole	ingress throughput	+37.22	[+37.11, +37.34]	1	Logs
➖	uds_dogstatsd_to_api_v3	ingress throughput	+0.00	[-0.13, +0.13]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	+0.00	[-0.09, +0.09]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	-0.02	[-0.15, +0.12]	1	Logs
➖	ddot_metrics_sum_cumulative	memory utilization	-0.35	[-0.51, -0.19]	1	Logs
➖	ddot_metrics_sum_cumulativetodelta_exporter	memory utilization	-0.52	[-0.75, -0.29]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	-0.63	[-0.67, -0.59]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	-0.65	[-1.04, -0.27]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	-0.66	[-1.16, -0.16]	1	Logs
➖	file_to_blackhole_500ms_latency	egress throughput	-0.67	[-1.06, -0.27]	1	Logs
➖	docker_containers_memory	memory utilization	-1.14	[-1.25, -1.03]	1	Logs
➖	ddot_metrics	memory utilization	-1.21	[-1.44, -0.99]	1	Logs
➖	ddot_metrics_sum_delta	memory utilization	-1.31	[-1.51, -1.12]	1	Logs
➖	ddot_logs	memory utilization	-1.72	[-1.79, -1.65]	1	Logs
➖	quality_gate_idle_all_features	memory utilization	-2.10	[-2.14, -2.06]	1	Logs bounds checks dashboard
➖	otlp_ingest_logs	memory utilization	-2.10	[-2.22, -1.98]	1	Logs
➖	quality_gate_idle	memory utilization	-2.55	[-2.60, -2.51]	1	Logs bounds checks dashboard
➖	docker_containers_cpu	% cpu utilization	-2.68	[-5.68, +0.32]	1	Logs
➖	file_tree	memory utilization	-2.76	[-2.81, -2.71]	1	Logs
➖	uds_dogstatsd_20mb_12k_contexts_20_senders	memory utilization	-2.79	[-2.84, -2.73]	1	Logs
➖	quality_gate_metrics_logs	memory utilization	-2.99	[-3.19, -2.78]	1	Logs bounds checks dashboard
➖	otlp_ingest_metrics	memory utilization	-3.14	[-3.29, -2.99]	1	Logs
✅	quality_gate_logs	% cpu utilization	-50.33	[-51.68, -48.98]	1	Logs bounds checks dashboard

Bounds Checks: ✅ Passed

perf	experiment	bounds_check_name	replicates_passed	links
✅	docker_containers_cpu	simple_check_run	10/10
✅	docker_containers_memory	memory_usage	10/10
✅	docker_containers_memory	simple_check_run	10/10
✅	file_to_blackhole_0ms_latency	lost_bytes	10/10
✅	file_to_blackhole_0ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency	lost_bytes	10/10
✅	file_to_blackhole_1000ms_latency	memory_usage	10/10
✅	file_to_blackhole_100ms_latency	lost_bytes	10/10
✅	file_to_blackhole_100ms_latency	memory_usage	10/10
✅	file_to_blackhole_500ms_latency	lost_bytes	10/10
✅	file_to_blackhole_500ms_latency	memory_usage	10/10
✅	quality_gate_idle	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_idle	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_idle_all_features	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_idle_all_features	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_logs	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_logs	lost_bytes	10/10	bounds checks dashboard
✅	quality_gate_logs	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	cpu_usage	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	lost_bytes	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	memory_usage	10/10	bounds checks dashboard

Explanation

Confidence level: 90.00%
Effect size tolerance: |Δ mean %| ≥ 5.00%

Performance changes are noted in the perf column of each table:

• ✅ = significantly better comparison variant performance
• ❌ = significantly worse comparison variant performance
• ➖ = no significant change in performance

A regression test is an A/B test of target performance in a repeatable rig, where "performance" is measured as "comparison variant minus baseline variant" for an optimization goal (e.g., ingress throughput). Due to intrinsic variability in measuring that goal, we can only estimate its mean value for each experiment; we report uncertainty in that value as a 90.00% confidence interval denoted "Δ mean % CI".

For each experiment, we decide whether a change in performance is a "regression" -- a change worth investigating further -- if all of the following criteria are true:

1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

2. Its 90.00% confidence interval "Δ mean % CI" does not contain zero, indicating that if our statistical model is accurate, there is at least a 90.00% chance there is a difference in performance between baseline and comparison variants.

3. Its configuration does not mark it "erratic".

CI Pass/Fail Decision

✅ Passed. All Quality Gates passed.

• quality_gate_metrics_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check cpu_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check lost_bytes: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_idle_all_features, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_idle_all_features, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check lost_bytes: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_idle, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_idle, bounds check intake_connections: 10/10 replicas passed. Gate passed.

[ArmentaRoberto]

Manual QA:

Agent v7.72 was OK

2026-01-29 22:52:35 UTC | CORE | DEBUG | (pkg/aggregator/demultiplexer.go:109 in func1) | Flushing serie: {"metric":"datadog.agent.check_ready","points":[[1769727155,1]],"tags":["status:python3","check_name:custom_checkvalue","agent_version_major:7","agent_version_minor:72","agent_version_patch:0"],"host":"i-0590c9125783a10e3","type":"gauge","interval":0,"source_type_name":"System"}

Agent v7.73 regression introduced

2026-01-29 22:46:05 UTC | CORE | DEBUG | (pkg/aggregator/demultiplexer.go:109 in func1) | Flushing serie: {"metric":"datadog.agent.check_ready","points":[[1769726765,1]],"tags":["status:python3","check_name:","agent_version_major:7","agent_version_minor:73","agent_version_patch:0"],"host":"i-0590c9125783a10e3","type":"gauge","interval":0,"source_type_name":"System"}

FIX

2026-01-30 02:00:25 UTC | CORE | DEBUG | (pkg/aggregator/demultiplexer.go:109 in func1) | Flushing serie: {"metric":"datadog.agent.check_ready","points":[[1769738425,1]],"tags":["status:python3","check_name:custom_checkvalue","agent_version_major:7","agent_version_minor:77","agent_version_patch:0"],"host":"i-0590c9125783a10e3","type":"gauge","interval":0,"source_type_name":"System"}
2026-01-30 02:00:40 UTC | CORE | DEBUG | (pkg/aggregator/demultiplexer.go:109 in func1) | Flushing serie: {"metric":"datadog.agent.check_ready","points":[[1769738440,1]],"tags":["status:python3","check_name:custom_checkvalue","agent_version_major:7","agent_version_minor:77","agent_version_patch:0"],"host":"i-0590c9125783a10e3","type":"gauge","interval":0,"source_type_name":"System"}
2026-01-30 02:00:55 UTC | CORE | DEBUG | (pkg/aggregator/demultiplexer.go:109 in func1) | Flushing serie: {"metric":"datadog.agent.check_ready","points":[[1769738455,1]],"tags":["status:python3","check_name:custom_checkvalue","agent_version_major:7","agent_version_minor:77","agent_version_patch:0"],"host":"i-0590c9125783a10e3","type":"gauge","interval":0,"source_type_name":"System"}