Audit existing Kestra flows, surface resilience / idempotency / guardrail gaps as a severity-ranked report, then apply the edits the user confirms.
This is the auditing counterpart to the sibling skills:
| Skill | Owns |
|---|---|
kestra-flow |
Authoring — create / modify / debug flow YAML from intent |
kestra-flow-hardening |
Auditing — find gaps, recommend + apply guardrails |
kestra-ops |
Operating — validate / deploy / run via kestractl |
Hand off to kestra-flow for "build a new flow" and to kestra-ops for "validate / deploy this".
When to use
Trigger on requests to harden, audit, review, or make production-ready / resilient / idempotent:
- "Harden this flow / these flows for production."
- "Audit my flow — what's missing for reliability?"
- "Add retries, timeouts, and error handling to this flow."
- "Review this namespace's flows for resilience gaps."
Do not use this skill to author a brand-new flow from a description — that is kestra-flow.
Required inputs
- One or more flows, in priority order:
- Inline YAML pasted into the chat
- File path(s), glob, or directory (e.g.
./flows/,./flows/*.yml) - Live instance — flows fetched via
kestra-ops/kestractl(the user pairs the skills; this skill does not require a running instance) - A namespace / directory batch
- Kestra version and edition (OSS / EE). Ask once if unknown; default to latest OSS. Used to gate version-/edition-specific recommendations.
Workflow
Step 1 — Fetch the flow schema (authoritative)
curl -s https://api.kestra.io/v1/plugins/schemas/flow
Read the raw JSON. The schema is the source of truth for which properties and types
exist in the target version. Never recommend a property absent from the schema — this is
what catches version traps such as retry.maxAttempt (pre-0.24) vs retry.maxAttempts.
Step 2 — Confirm scope and context
- Resolve the input form (paste / file / glob / dir / namespace).
- Confirm version + edition (default latest OSS if not given).
- For a directory or namespace, gather all target flows before reporting.
Step 3 — Calibrate by flow signals (proportionality)
Hardening must be proportional to what the flow does and where it runs. Read these signals and tailor the audit — do not apply a fixed checklist to every flow:
- Triggers / scheduling present → concurrency, SLA, and overlap behavior become relevant; a manually-run flow needs them far less.
- Real side-effects (writes, external calls, cloud jobs, scripts) → resilience and idempotency findings matter; a pure-compute or log-only flow does not need them.
- Namespace as env hint —
prod.*/staging.*raises the bar;dev.*/sandbox.*/tutorial.*gets a lighter touch ("this looks like dev — hardening deferred unless you're promoting it"). - Controls already present → acknowledge them; never re-flag what's already there.
Never invent risk. If a flow is genuinely sound, returning "No critical or high findings; this flow is reasonably hardened" is a correct, encouraged outcome. Do not manufacture Low-severity nits to look busy.
Step 4 — Run the audit taxonomy
Evaluate each relevant dimension. For exact, copy-pasteable YAML per construct and the
"when to apply / when NOT to" guidance, load
references/hardening-patterns.md.
Resilience
- Retries on transient-failure-prone tasks (HTTP, JDBC, cloud APIs) — see idempotency tiers below.
- Timeouts on every runnable task (scripts, queries, cloud jobs — hang and cost control).
- Flow-level
retrywhere whole-execution replay makes sense.
Failure handling
errors(global) for alerting; localerrorsinside flowable tasks for targeted cleanup.finallyfor resource teardown (containers, temp infra) — runs while execution is still RUNNING.afterExecutionfor final-state-based notifications (SUCCESS / FAILED / WARNING) viarunIf.allowFailure/allowWarningon genuinely non-critical tasks only.
Concurrency & idempotency
concurrencylimit +behavior(QUEUE / CANCEL / FAIL) for flows hitting shared / rate-limited systems.- Idempotency guard —
system.correlationId+ duplicate check (EE) or KV-based state guard (OSS). - Trigger
allowConcurrent/ Schedule overlap behavior.
Guardrails & contracts
checks(≥ 1.2) for pre-execution input validation.sla—MAX_DURATION/EXECUTION_ASSERTIONwith breach labels + alerting.- Input typing —
SELECT/ENUM/SECRETinstead of looseSTRING.
Hygiene
- Subflow extraction when a flow exceeds ~100 tasks or bloats the execution context.
store: true/storesfor large outputs instead of carrying data in the execution context.- Descriptions, labels, naming conventions.
- No hardcoded secrets / credentials (reuse
kestra-flow's rule — see Shared rules below).
Platform-fit & maintainability (advisory — not hardening, never a blocker) These are recommendations, not risks. They never carry a severity and never block; they surface in a separate Advisory section (see report format). Use them to nudge users toward better-maintained flows, not to gate anything.
- Long inline scripts → Namespace Files. A
Scripttask with a large inlinescript:/commands:block (roughly > 15–20 lines, or containing real program logic) is harder to read, test, and version. Recommend moving the code into a Namespace File and calling it from aCommandstask (namespaceFiles: {enabled: true, include: [...]}), or reading it viaread('path')in aScripttask. Kestra's own guidance:Commandsfor production workloads,Scriptfor quick iteration. - Scripts duplicating plugin functionality → native plugin. When a script reimplements
something a Kestra plugin already does, recommend the native task — less custom code to
maintain. Pattern-match common usage to plugin families and verify the task exists in the
fetched schema before naming it:
curl/wget/requests→io.kestra.plugin.core.http.Request/Downloadpsql/mysql/sqlite3→ the matching JDBC plugin (io.kestra.plugin.jdbc.*)aws/gcloud/azCLI → the cloud plugins (io.kestra.plugin.aws|gcp|azure.*)dbt→io.kestra.plugin.dbt.*;gitclone →io.kestra.plugin.git.Clone
- If Namespace Files are available in context, assess how much of the scripted logic could be replaced by native tasks and quantify it ("~X of N steps map to native plugin tasks").
Step 5 — Classify each finding by severity
| Severity | Definition | Example |
|---|---|---|
| Critical | Will cause data corruption, duplicate side-effects, or silent loss in production | Retry / allowFailure on a non-idempotent write; no concurrency limit on non-atomic state updates; hardcoded secret |
| High | Will cause outages / hangs / cost-blowouts or undetected failures | No timeout on a cloud / script task; no errors alerting; no SLA on a business-critical schedule |
| Medium | Degraded resilience / recoverability | Missing transient retries on HTTP / JDBC; no finally teardown leaking resources; loose input typing |
| Low | Hygiene / maintainability | Missing descriptions / labels; naming; large-output store unset |
Platform-fit recommendations (long scripts → Namespace Files; scripts → native plugins) are not assigned a severity. They are reported separately as Advisory and never block.
Step 6 — Apply the idempotency judgment (before recommending retries)
A retry is good advice for a flaky read and catastrophic for a non-idempotent write (double-charge, duplicate insert). Classify every candidate task before recommending:
| Tier | How detected | Retry recommendation |
|---|---|---|
| Safe | Read-only by type (HTTP GET, SELECT, fetch / list, Log) | Recommend retries freely |
| Conditionally safe | Write with a natural idempotency key, or transactional / upsert task | Recommend retries with the precondition stated |
| Unsafe / unknown | Opaque scripts, POST / PUT to unknown endpoints, non-transactional writes | Do NOT recommend a blind retry. Flag the idempotency question in the report with both branches: dedup guard (correlationId / KV) vs. retry-if-safe. Let the user decide at confirm-time. |
Step 7 — Emit the report
Format (findings numbered globally so the user can select by number):
## Hardening audit: <flow id> (<namespace>, v<X.Y>, OSS/EE)
### Critical
1. **<title>** — `tasks.<id>`
Risk: <what breaks in production if unfixed>
Caveat: <e.g. only safe if this endpoint dedupes on a key>
Proposed: <the edit, or both branches for unknown-safety tasks>
### High
2. ...
### Medium
### Low
### Advisory (platform-fit) — not hardening, optional
- **Long inline script** — `tasks.transform`
Move the ~40-line script into a Namespace File and call it from a `Commands` task
(versioned, testable, editable in the Code Editor).
- **Script duplicates a plugin** — `tasks.fetch`
This `curl` shell task can be `io.kestra.plugin.core.http.Request` (verified in schema).
---
Summary: N Critical · N High · N Medium · N Low · N Advisory
Reply with the numbers to apply (e.g. `1,4,7`), `all`, or `none`.
- Group by severity; each finding states risk + caveat + proposed fix + severity.
- Diffs are deferred to confirm-time — keep the report scannable.
- Mark structural edits (idempotency-guard insertion, flow-level retry behavior) clearly, since they add tasks rather than tweak one line.
- Batch: emit one consolidated report ranked by severity across all flows, with a per-flow summary table; then edit flow-by-flow on confirm.
- EE-only findings (e.g. correlationId guard): always label as EE, give the OSS fallback (KV guard), and frame the EE path as a value-add.
Step 8 — Apply confirmed edits
On apply 1,4,7 / all:
- Surgical, structure-preserving edits. Touch only the relevant tasks / blocks. Preserve root
id/namespace, task ordering, and comments. Never restructure unrelated parts. - File input → edit the file in place. Pasted YAML → return the modified YAML. Batch → edit each file.
- Re-validate every edit against the fetched schema (properties and types must exist).
- The initial number-selection is informed consent (the report already stated each risk / caveat) — do not re-prompt per finding, but show the diff as you apply it.
- Suggest
kestractl flow validate(viakestra-ops) as an optional final gate; do not require a live instance.
Shared rules (inherited from kestra-flow)
Do not restate — reuse the kestra-flow skill's rules so they don't drift:
- Schema compliance — only schema-defined task types and properties.
- No hardcoded secrets / credentials — use
inputsof typeSECRETor{{ secret('...') }}. - Quoting — prefer double quotes; single quotes inside when needed.
- Structural preservation — touch only the relevant part; preserve
id/namespace.
Example prompts
- "Harden this flow for production." (inline paste)
- "Audit
./flows/ingest.ymland add retries and timeouts where safe." - "Review all flows in
./flows/for resilience gaps and rank them worst-first." - "Make this scheduled flow idempotent — it sometimes runs twice." (idempotency tier judgment)
- "Add alerting and an SLA to this business-critical flow."