dependabot-fix

name	dependabot-fix
description	Comprehensively diagnose and fix a failing Dependabot PR. Use this skill when asked to run /dependabot-fix <pr-number>. The user provides the PR number in their prompt. The skill loads PR context, surveys errors at a high level, ingests relevant repo instructions / docs / source via subagents, performs a deep root-cause diagnosis, designs a risk-tiered fix with a manual testing strategy, commits the fix directly to the Dependabot PR branch, posts a REPORT.md as a comment on it (never commits it), and evaluates whether the skill itself needs updating afterwards.
allowed-tools	shell

Dependabot Fix

Systematically fix a failing Dependabot PR. The user provides a PR number (e.g., /dependabot-fix 142).

This skill spans five phases (A–E). Do not start editing code until Phase D is complete. Do not dive into logs until Phase B is complete.

Set up scratch space once at the start:

mkdir -p ./tmp && touch ./tmp/null
PR_NUM=<from user prompt>
REPO=axsaucedo/kaos

---

Phase A — Context

Step 1 · PR context

Fetch metadata and produce a one-paragraph written summary of the PR (ecosystem, directory, grouping, size, whether it is a security update, which files it touches). Do not open source files yet.

gh pr view $PR_NUM --repo $REPO --json title,body,headRefName,labels,files,mergeable,createdAt
gh pr diff $PR_NUM --repo $REPO | head -200

Identify:

• Ecosystem: github_actions | gomod | uv / pip | npm | docker
• Directory scope (/, operator/, pydantic-ai-server/, kaos-cli/, kaos-ui/, operator/tests/, mcp-servers/*, docs/)
• Grouping: single-dep vs grouped (all, all-security)
• Size: list number of files and approximate LOC changed

Step 2 · High-level error survey

List failing checks and capture the first and last error line from each failing job log. Do not investigate their meaning yet — just enumerate symptoms.

gh pr checks $PR_NUM --repo $REPO

# For each failing check, grab job ID from the URL and pull logs
gh run view --job <JOB_ID> --repo $REPO --log 2>./tmp/null \
  | grep -iE "error|exit code|##\[error\]|FAILED|assert|timed ?out" \
  | head -20 > ./tmp/pr-${PR_NUM}-symptoms.txt

Output should be a bullet list such as:

• go-tests/unit-tests: controller-tools@v0.20.1 requires go >= 1.25.0
• kaos-ui-tests/unit: TypeError: Cannot read properties of undefined (reading 'forEach') in dashboard.test.ts
• python-tests/pydantic-ai-server: AssertionError: expected 2 tool calls, got 3

---

Phase B — Context ingestion via subagents

Spawn three parallel explore subagents to load repo knowledge scoped to the touched ecosystems. Do not read any of this yourself beforehand — delegate.

Step 3 · Instructions subagent

Ask it to read .github/instructions/*.instructions.md files relevant to the PR's touched paths and summarize conventions, test commands, and gotchas.

Mapping guide (pass relevant ones to the subagent):

• operator/** or gomod bumps → operator.instructions.md, e2e.instructions.md
• pydantic-ai-server/**, kaos-cli/**, uv / pip bumps → python.instructions.md
• kaos-ui/** or npm bumps in kaos-ui/ → kaos-ui.instructions.md, kaos-ui-components.instructions.md, kaos-ui-testing.instructions.md, kaos-ui-kubernetes-types.instructions.md
• docs/** or npm bumps in docs/ → docs.instructions.md
• .github/workflows/** (github_actions PRs) → release/CI-relevant instructions from above, plus .github/copilot-instructions.md

Step 4 · Docs subagent

Ask it to read matching docs/ pages for the changed modules: module overview, testing notes, architecture diagrams. Return a briefing no longer than ~40 lines covering what the module does, its public surface, and how it is tested.

Step 5 · Codebase subagent

Ask it to produce a targeted map:

• Primary source directories and entry points for the touched area
• Build and test commands (e.g. make test-unit, npm run test:unit, python -m pytest …)
• Integration/E2E entry points (operator/tests/e2e, kaos-ui/tests/**)
• Any Makefile targets that generate code (make generate manifests, make helm)
• Docker images built from this code (for local reproduction)

The three subagent briefings together form the working context for Phase C.

---

Phase C — Deep root-cause diagnosis

Step 6 · Diagnose

Now — and only now — dive into the failing-job logs with full context from Phase B. For each failing check, trace the first meaningful error back to:

1. A direct regression from the bumped dep (removed symbol, signature change, behaviour change, stricter validation)
2. A transitive toolchain issue (e.g. @latest pulling a newer Go/Node/Python; post-install script requiring newer runtime)
3. Pre-existing test fragility exposed by a harmless dep bump
4. Infra flake (post-job cancellation after tests passed, timeouts, registry rate-limits)

For a grouped PR, diagnose each failing check separately — failures may have independent causes. Record findings in ./tmp/pr-${PR_NUM}-diagnosis.md.

---

Phase D — Fix design

Step 6.5 · Scope triage — is this a fix, or a Dependabot config problem?

Before planning a fix, check whether the PR is in-scope for fixing at all. A grouped Dependabot PR that bundles framework-migration majors cannot be fixed in a single pass; the right move is to reconfigure .github/dependabot.yml so the majors come through individually.

Scope-reject triggers (any one is sufficient):

• A single group PR contains ≥ 2 major bumps on framework-tier packages
• A major bump on: react, react-dom, react-router-dom, vite, vitest, @tanstack/react-query, tailwindcss, typescript, eslint, zod, zustand (npm); controller-runtime, k8s.io/*, pydantic, pydantic-ai, litellm (other ecosystems) when bundled with unrelated updates
• The PR touches > ~40 packages and the majority are routine but a minority are migrations

When triggered, do not attempt a fix and do not close the PR yourself — leave it open for the host to close. Instead:

1. Update .github/dependabot.yml to split the offending group (typically add update-types: ["minor", "patch"] to the all group so majors get individual PRs).
2. Open that config change as a separate small PR (leave it for the host to review/merge).
3. Verbalise the scope-reject decision as a comment on the original Dependabot PR(s): explain why it cannot be fixed in one pass, link the config PR, and recommend the host close it once smaller PRs replace it next cycle. Leave the PR open — do not pause for a decision, do not close it.
4. Skip Phase E's "commit on Dependabot branch" flow — there is no fix. The REPORT.md content can be folded into that comment.

Security-update groups (all-security) are usually left bundled because security majors are rare and time-sensitive — only split them if a concrete blocker (e.g. a framework major) forces it.

Step 7 · Comprehensive plan

Write a plan covering the following; scale depth to risk:

Section	Always	If risk ≥ medium
Root cause	✅	✅
Files expected to change	✅	✅
Fix approach (and alternatives considered)	✅	✅
Risk rating (low/medium/high)	✅	✅
Reproduction steps	✅	✅ (must be executable)
Manual testing strategy	✅	✅ expanded
Rollback plan		✅
Blast radius (API / CRD / wire format / user-facing output)		✅

Risk ≥ medium if any of:

• bump touches public API of an exported library (gomod, kaos-cli, pydantic-ai-server)
• changes a Kubernetes CRD generated surface
• changes an HTTP/JSON-RPC wire format
• changes a runtime image that ships in a release

Step 8 · Manual testing strategy (tiered)

Tier the effort by Step 7's risk rating:

• Low (isolated) — apply fix, run the narrowest relevant suite (e.g. one pytest file, one vitest spec, go test ./pkg/...). No reproduction step needed.
• Medium (cross-module or cross-ecosystem) — first reproduce the failure on main locally to prove the regression is real (not a harness artefact). Then apply the fix, retest, and confirm the reproduction no longer fires.
• High (runtime / wire) — reproduce against a locally-built Docker image for the affected component (see ecosystem appendix). If it touches operator/agent behaviour, bring up a KIND cluster per .github/instructions/e2e.instructions.md and run 1–3 E2E tests locally before pushing.

Keep all scratch output under ./tmp/. Use ./tmp/null as the sink when suppressing output:

python -m pytest tests/test_x.py -v 2>./tmp/null

---

Phase E — Finalise

Step 9 · Ship directly on the Dependabot PR

Keep it simple: commit fixes on the existing Dependabot PR branch. No replacement PR, no cherry-picking.

gh pr checkout $PR_NUM --repo $REPO

# ...make edits...
git add -A
git commit -m "ci(<scope>): <one-line summary>

Root cause: <one sentence>
Fix: <one sentence>
Testing: <how verified>

Co-authored-by: Copilot <[e-mail]>"

git push

Monitor CI; rerun known flakes once before investigating:

gh pr checks $PR_NUM --repo $REPO
gh run rerun <run-id> --failed --repo $REPO  # only for known flakes

Merge when green — but for kaos-ui framework major bumps, leave the PR open for human review instead of merging (see Step 9.5):

gh pr merge $PR_NUM --repo $REPO --merge

Caveats:

• Do not use @dependabot rebase after pushing fix commits — it will discard them. Let the PR merge as-is.
• If Step 9.5 says leave-open (kaos-ui framework major), do not merge. Post the report and leave the PR open; the host merges after their own visual review.

Step 9.5 · kaos-ui review gate (framework majors only)

The visual/E2E suite for kaos-ui is stringent, so minor and patch bumps — including framework packages — can be merged directly once CI is green. No human gate is needed for them.

For a kaos-ui major bump on a framework package (react, react-dom, react-router-dom, vite, vitest, @tanstack/react-query, tailwindcss, typescript, eslint, zod, zustand), CI alone is insufficient evidence — major-version visual regressions can slip past Playwright assertions. Do not merge. Instead:

1. Push the fix commits so CI is green.
2. Post REPORT.md as a PR comment (Step 10), explicitly noting it is a framework major held for human visual review.
3. Leave the PR open. The host reviews and merges manually.

Bump type (kaos-ui)	Action
Minor / patch (any package)	Merge directly when green (Step 9 gh pr merge)
Major on framework package	Do NOT merge. Post report, leave open for human review

Do not use the ask_user tool or any in-chat prompt as a merge gate — it does not reliably block execution. The gate is simply "leave the major PR open"; the human review happens on the PR itself.

Step 10 · REPORT.md as PR comment — never commit

Write REPORT.md at the repo root (gitignored) covering: PR context, symptoms, root cause, fix plan + testing evidence, CI/merge outcome. Then:

gh pr comment $PR_NUM --repo $REPO --body-file REPORT.md

Step 10.6 · Emit a machine-readable result line

As the final line of output, print exactly one status line so an orchestrator (e.g. /dependabot-fix-all) can classify the outcome without parsing prose:

RESULT: <merged|left-open|superseded|blocked> pr=<PR_NUM> reason="<short phrase>"

• merged — fix pushed, CI green, PR merged.
• left-open — CI green but intentionally not merged (kaos-ui framework major held for human review).
• superseded — scope-rejected; dependabot.yml split PR opened + comment posted, original left open for host to close.
• blocked — could not be fixed this run (record why in reason).

This skill runs fully non-interactive / autopilot: never call ask_user or ask questions in any mode — resolve every decision autonomously per the policies above and emit the RESULT line.

Step 11 · Evaluate skill currency

After the PR merges, ask whether this run surfaced a major, repeatable learning that future runs would miss without it. Examples:

• A new failure pattern not in the appendix (new ecosystem, new toolchain)
• A repo-level invariant that changed (e.g. Go toolchain bump, new CI job name)
• A workflow step that proved redundant in practice

If yes — and only if the learning is non-obvious — open a small follow-up PR updating this SKILL.md. Resist adding minor details that a competent operator would infer; bloat degrades the skill.

---

Invariants

• Work directly on the Dependabot PR branch; do not open replacement PRs
• Never @dependabot rebase after pushing fix commits (it discards them)
• Prefer version pinning over version rollback for @latest toolchain drift
• Scratch files under ./tmp/ (never /tmp/); suppress output with 2>./tmp/null
• Conventional-commit style with Copilot co-author trailer
• REPORT.md is posted as a PR comment, never committed
• Runs fully non-interactive (autopilot); the final output line is the RESULT: status line (Step 10.6)

---

Appendix · Ecosystem cheat-sheet

Common failure modes observed on bundled Dependabot PRs in this repo. Treat these as hypotheses, not diagnoses — Phase C must still verify.

github_actions (e.g. PR #142)

• @latest tool installs in workflows or Makefiles silently bumping to a version that requires a newer Go/Node toolchain
  • Fix: pin to the last version compatible with go.mod / .nvmrc (e.g. controller-tools@v0.19.0, setup-envtest@release-0.22, helmify@v0.4.18)
• actions/upload-artifact@v4 name-collision within matrix jobs → add a matrix suffix to the artifact name
• actions/setup-node major bump dropping support for older Node versions → check .nvmrc alignment
• Known flakes to rerun: e2e/E2E (example-autonomous) — post-job cancellations and kaos agent a2a send exit-1 flakes

gomod (e.g. PR #141)

• controller-runtime bumps often require regenerating CRDs and RBAC: cd operator && make generate manifests
• k8s.io/* bumps may require bumping setup-envtest branch (release-0.X) to match
• API rename/removal from sigs.k8s.io/* — use go doc <pkg>.<symbol> in the new version to find the replacement
• Local reproduction: cd operator && make test-unit

uv / pip (e.g. PR #125, #145)

• pytest majors sometimes deprecate fixtures; look for PytestDeprecationWarning
• litellm, pydantic-ai minors can change tool-calling response shape; check DEBUG_MOCK_RESPONSES mocks
• cryptography majors drop old cipher suites — affects anything using custom TLS
• Local reproduction: cd <pkg> && source .venv/bin/activate && python -m pytest tests/ -v
• For E2E deps (operator/tests/): cd operator/tests && source .venv/bin/activate && make e2e-test (requires KIND)

npm in kaos-ui/ (e.g. PR #143, #146)

• Scope-reject first (see Step 6.5). React / React Router / Vite / Vitest / Zod / Zustand / Tailwind majors bundled with routine bumps = reconfigure dependabot.yml and leave the PR open with a comment for the host to close, don't fix.
• Risk is automatically high for any kaos-ui PR with a major bump on a framework package — visual regressions do not show up in CI.
• Local reproduction: cd kaos-ui && npm ci && npm run build && npm run lint && npm run test:unit
• Playwright required, not optional: npm run test:e2e against a running dev server + kaos ui --no-browser proxy + KIND cluster (per kaos-ui-testing.instructions.md). CI's E2E alone is not sufficient evidence.
• Merge policy (Step 9.5): kaos-ui minor/patch bumps merge directly when CI is green; framework major bumps are left open for human review, never auto-merged. No ask_user gate.
• Common breakage: vitest majors change config shape and matcher behaviour; react-router majors change route definitions; @tanstack/react-query majors change useQuery signature; ESLint 9 flat-config drift when eslint-* plugins bump.
• Lockfile desync is the dominant failure mode on routine grouped PRs — every UI check fails at npm ci with Missing: <pkg> from lock file. Fix: delete both node_modules and package-lock.json, then npm install. Deleting only node_modules can trigger a secondary Cannot find native binding error from rolldown/vitest 4.x optional deps.

npm in docs/ or root

• VitePress / mermaid plugin API drift — verify npm run build under docs/
• Root-level tooling bumps rarely affect runtime; usually a simple rebuild suffices

docker

• Base-image bumps (e.g. golang:1.25-alpine) must match go.mod toolchain line
• Multi-arch buildx bumps require local docker buildx create --use