460-helm

460-helm is a cursor rule for coding agents from d-padmanabhan/agent-engineering-handbook. It costs 0 tokens per session (567 once invoked), scanned A, original, MIT.

A set of mandatory rules for validating Helm charts, which are templates used to deploy applications to Kubernetes.

In plain words
What is it for?
Use it to enforce safe chart values, dependency and lock-file consistency, secret handling, immutable image digests, and pre-deployment checks.
Why use it?
It catches chart, configuration, secret-management, supply-chain, and deployment risks before installation or upgrade.

Cursor rule

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/d-padmanabhan/agent-engineering-handbook/460-helm
Clone the repo
git clone --depth 1 https://github.com/d-padmanabhan/agent-engineering-handbook

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for 460-helm

README.md
[![agentmods](https://agentmods.dev/badge/rules/d-padmanabhan/agent-engineering-handbook/460-helm.svg)](https://agentmods.dev/rules/d-padmanabhan/agent-engineering-handbook/460-helm)
Your own site
<a href="https://agentmods.dev/rules/d-padmanabhan/agent-engineering-handbook/460-helm"><img src="https://agentmods.dev/badge/rules/d-padmanabhan/agent-engineering-handbook/460-helm.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 567 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00567
Opus 5 $0.00000 $0.00283
Sonnet 5 $0.00000 $0.00113
Haiku 4.5 $0.00000 $0.00057

Measured 4d ago against content hash 48d5edcc14c3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

460-helm scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

rules/460-helm.mdc · 43 lines

How it starts

The opening of the file, as written. The whole thing — 43 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Helm Engineering Gates

This rule owns mandatory policy only. Use the Kubernetes containers skill (${HANDBOOK_ROOT}/skills/kubernetes-containers/SKILL.md) and Helm chart reference (${HANDBOOK_ROOT}/skills/kubernetes-containers/references/helm-charts.md) for chart structure, templating, testing, GitOps, and troubleshooting.

Chart and Values Contract

  • Keep chart metadata, dependency constraints, generated Chart.lock, and vendored dependencies consistent. Review lock changes as supply-chain changes.
  • Define safe defaults and validate user-facing values with values.schema.json when practical.
  • Quote strings deliberately, use explicit types, and fail rendering for required values rather than silently producing invalid resources.
  • Centralize stable naming and labels in helpers; avoid templates whose output depends on ambient cluster state unless that dependency is explicit and tested.
  • Do not place credentials or rendered secret values in committed values files, command lines, logs, diffs, or release notes.
  • Production workloads must resolve to immutable image digests.

Preflight and Mutation

  • Before any install or upgrade, run helm lint and render with the exact intended values using helm template.
  • Validate rendered manifests with repository policy checks and an admission-aware dry-run when available.
  • Inspect the release, namespace, cluster, chart version, values sources, rendered diff, hooks, CRDs, and deletion impact before mutation.
  • helm install, helm upgrade, helm rollback, helm uninstall, dependency publication, and registry publication are remote mutations requiring explicit authorization under the agent audit rule (${HANDBOOK_ROOT}/rules/020-agent-audit.mdc).
  • Do not use --force, --no-hooks, --disable-openapi-validation, or broad cleanup flags as routine recovery.

Verification and Recovery

  • Use bounded waits and verify release status, workload rollout, hooks, events, health, and expected resource ownership.
  • Use --atomic only when its rollback semantics are understood and safe for hooks, migrations, CRDs, and stateful changes.
  • Prefer a reviewed values/chart fix or Git revert. Direct cluster patches create drift and must be break-glass, recorded, bounded, and reconciled immediately.

Read the full file on GitHub · 43 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 43 lines · 0 tokens per session scan A 48d5edcc14c3

Subscribe to this mod's changes

460-helm is a cursor rule published in the GitHub repository d-padmanabhan/agent-engineering-handbook (16 stars, last pushed 4d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 567 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.