mcpbeat

Dd Triage Flaky Test

datadog/dd-triage-flaky-test

Load when investigating a specific flaky test. Gets history, failure pattern, and category, then recommends fix, quarantine, or escalate.

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the whole folder, loaded on every use
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copies elsewhere
how many repositories repackaged it
967
stars on the repo
on the repository, not the skill itself

Install

one command, takes just this skill from the repository
npx skills add https://github.com/DataDog/pup --skill dd-triage-flaky-test

The instruction itself

9 sections, as written by the author

Triage Flaky Test

One-line summary: Investigate a specific flaky test — get history, failure pattern, and category, then recommend fix, quarantine, or escalate.

Requires: dd-pup skill (pup CLI installed and authenticated).


Input

| Parameter | Description |

|---|---|

| Test name | Fully qualified test name (e.g. TestMyFunc or com.example.MyTest) |

| Repository | Lowercase, no-schema URL (e.g. github.com/org/repo). Derive from git remote get-url origin if not provided. |


Workflow

STEP 0 — Parse Input

Derive repository ID from git if not provided:

git remote get-url origin
# Strip protocol and trailing .git, then lowercase the result
# e.g. https://github.com/DataDog/my-repo.git → github.com/datadog/my-repo

Validation fallback: If STEP 1 returns no results, confirm the correct repository by searching without a repo filter:

pup cicd tests search \
  --query "@test.name:\"<test-name>\"" \
  --from 30d \
  --limit 5

Extract @git.repository.id_v2 from results and retry STEP 1 with the confirmed value.

STEP 1 — Get Flaky Test Details

Preferred — use fingerprint_fqn if known (fingerprint_fqn is a valid CI Visibility search facet, distinct from flaky_state):

pup cicd flaky-tests search \
  --query "fingerprint_fqn:<fqn>" \
  --sort="-last_flaked" \
  --limit 5

Fallback — use name + suite + repo:

pup cicd flaky-tests search \
  --query "@test.name:\"<test-name>\" @test.suite:\"<suite>\" @git.repository.id_v2:\"<repo>\"" \
  --sort="-last_flaked" \
  --limit 10

Omit @test.suite if unknown; if the same test name appears in multiple suites, pick the entry whose suite matches the failing test.

Do not filter by flaky_test_state — return the test regardless of state.

Note: the query filter facet is flaky_test_state; the returned response attribute is flaky_state — these are different names for the same concept; do not use flaky_state:active as a query filter.

Extract from results:

  • fingerprint_fqn — unique test identifier; used as the id in STEP 5 write call. If absent, do not proceed to quarantine — see STEP 5.
  • flaky_state — current state (active / quarantined / disabled / fixed)
  • test_stats.failure_rate_pct — percentage of runs that fail
  • flaky_category — root cause category
  • codeowners — owning team
  • pipeline_stats.total_lost_time_ms — total CI time lost

STEP 2 — Get Recent Failure History

pup cicd tests search \
  --query "@test.name:\"<test-name>\" @test.suite:\"<suite>\" @test.status:fail @git.repository.id_v2:\"<repo>\"" \
  --from 7d \
  --limit 20

Extract:

  • Error messages and stack traces (@error.message, @error.stack)
  • Failing branches (@git.branch) — branch-specific vs. widespread
  • Frequency pattern — random timing or specific conditions
  • Unique @ci.pipeline.id values for blast radius (STEP 3)

STEP 3 — Check Blast Radius

Count distinct pipelines impacted using pipeline IDs from STEP 2:

pup cicd events aggregate \
  --query "@ci.status:error @ci.pipeline.id:(<id1> OR <id2> OR ...) @git.repository.id_v2:\"<repo>\"" \
  --compute count \
  --group-by "@ci.pipeline.name" \
  --from 7d

Use the first 10 pipeline IDs from STEP 2 (cap at 10; if more are available, run a second batch and merge results by summing counts per @ci.pipeline.name across batches). Report blast radius as: total number of unique pipelines impacted and whether failures are branch-specific or widespread.

Note: a pipeline failure is not necessarily caused solely by this flaky test — treat blast radius as a signal, not a definitive count.

STEP 4 — Recommend Fix or Quarantine

Use flaky_category from STEP 1 and error messages from STEP 2.

Root cause first:

  • Read the full error trace from bottom to top — chained errors hide the real cause; the innermost error is the root cause, not the first line.
  • Identify the exact source of nondeterminism (race, ordering, stale state, timing).
  • If the root cause is a CI infrastructure problem (runner unavailable, Docker daemon failure, network outage) → do NOT propose a code fix; classify as infra and recommend retry instead.
  • If root cause is uncertain and cannot be confirmed from the stack trace → skip fix, go to quarantine.

Fix at the correct layer:

  • Test issue → fix in test or test helper only.
  • Production bug exposed by the test → fix in production code.
  • Shared helper used by multiple tests → fix the helper AND update all call sites; never patch a single test when the root cause is in shared code.

Forbidden — do not propose these:

  • Timing hacks: increasing timeouts, adding sleeps, widening time windows, adding retries. A fix that only reduces flake probability without eliminating the root cause is invalid.
  • Masking: relaxing assertions (e.g., exact match → at least 1), dropping validations.
  • Partial fixes: touching one call site when multiple share the root cause.

Fix patterns by category:

| Category | Approach |

|---|---|

| timeout | Identify the slow operation and make it synchronous or deterministic — do NOT simply raise the timeout constant |

| concurrency | Add deterministic synchronization (barriers, channels, locks); remove shared mutable state between tests |

| network | Mock or stub network calls at the boundary; if the test requires a real connection, isolate it with a test server |

| time | Inject a controllable clock; replace wall-clock assertions with relative or event-driven checks |

| order_dependency | Isolate test state with setup/teardown; eliminate dependencies on execution order or global state |

| environment_dependency | Mock env variables and external config; use test-local fixtures, not shared directories or singletons |

| resource_leak | Ensure every resource opened in a test is closed in teardown; use cleanup hooks that run even on failure |

| randomness | Fix the random seed for the test run; use deterministic inputs instead of random generation |

| asynchronous_wait | Replace fixed sleeps with condition polling or event/signal-driven waits with a hard timeout |

| io | Use temp files/dirs cleaned up in teardown; mock or stub filesystem interactions |

| unknown | Skip fix attempt → go to quarantine |

Before proposing code changes, verify all of the following — if any fails, skip fix and recommend quarantine:

  • The root cause is the innermost error in the trace, not a surface-level symptom.
  • The failure is a code problem, not a CI infrastructure problem.
  • The fix eliminates the root cause (not just reduces flake probability).
  • The fix is at the correct layer (test vs. production vs. shared helper).
  • All call sites of any shared code are updated.
  • No timing hacks or relaxed assertions introduced.

Decision:

  • If category is unknown OR verification above fails → skip fix, recommend quarantine
  • If category is known AND root cause is confirmed AND fix is valid → propose specific code change

STEP 5 — Produce Triage Brief and Act

Flaky Test Triage Brief
=======================
Test:           <fully qualified test name>
Service:        <@test.service>
Category:       <flaky_category>
Failure Rate:   <test_stats.failure_rate_pct>%
Duration Lost:  <pipeline_stats.total_lost_time_ms>ms
Codeowners:     <codeowners>
Blast Radius:   <N> pipelines (<branch-specific | widespread>) [approximate — other failures in the same pipeline runs may not be related]

Evidence:
  <1-2 key error message lines from STEP 2>

Recommendation: <fix | quarantine | escalate>
Confidence:     <high | medium | low>
Action:         <specific next step>

Decision thresholds:

  • failure_rate_pct > 10 OR blast radius > 5 pipelines → quarantine
  • failure_rate_pct ≤ 10 AND known category AND clear fix → fix
  • failure_rate_pct ≤ 10 AND category unknownescalate to codeowners with triage brief

If recommending quarantine, present and require explicit user approval before writing:

Proposed action: quarantine "<test-name>"
  id (fingerprint_fqn): <fingerprint_fqn from STEP 1>
  Effect: test still runs but failures are suppressed (CI will not be blocked)
  Reversible: yes — update new_state to active to restore

Approve? (yes/no)

If fingerprint_fqn was not returned in STEP 1 (test not yet in FTM or query returned no results): do not attempt the write. Surface an error and ask the user to open the Flaky Test Management UI directly to quarantine manually.

Only after explicit approval and a confirmed fingerprint_fqn, write the body file and run:

cat > /tmp/flaky-update.json <<'EOF'
{
  "data": {
    "type": "UpdateFlakyTestsRequest",
    "attributes": {
      "tests": [{"id": "<fingerprint_fqn>", "new_state": "quarantined"}]
    }
  }
}
EOF
pup test-optimization flaky-tests update --file /tmp/flaky-update.json

To undo: repeat with "new_state": "active".

How to use it

Copy the folder

Take datadog/dd-triage-flaky-test from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.