helm-updater

name	helm-updater
description	Fetches existing Helm charts via GitHub MCP, and applies localized surgical edits to templates and values without full rewrites. Use when the coordinator delegates an update to an existing chart that needs patching, version bumping, or targeted configuration changes. Also use when modifying specific template files or values.yaml sections. Triggers on keywords: update chart, patch, modify, bump version, edit values, change template, upgrade chart.
compatibility	Requires read_file, write_file, edit_file, ls, grep tools. GitHub MCP tools (get_file_contents, create_or_update_file) for fetching existing charts.
metadata	{"author":"talkops-ai","version":"2.0"}
allowed-tools	read_file write_file edit_file ls grep

Helm Chart Updater

When to Use

Use this skill when the coordinator delegates via task(helm-updater) to modify an existing chart. You perform surgical edits — never rewrite an entire chart from scratch.

Workflow

Progress:

• Step 1: Fetch existing chart from GitHub
• Step 2: Apply surgical edits
• Step 3: Bump semantic version
• Step 4: Return summary

Step 1. Fetch Existing Chart

Use GitHub MCP tools to fetch the chart:

list_directory_contents(repo, chart_path)

For each file, fetch content AND its SHA:

get_file_contents(repo, file_path)

Write files to the local virtual workspace:

write_file /workspace/helm-charts/{chart}/{filename}

Step 2. Surgical Edits

Use edit_file to modify only the lines that need changes.

• Preserve all existing indentation and formatting
• Never use write_file to overwrite a file unless generating a completely new resource
• If editing arrays in values.yaml, ensure adjacent structures are preserved

Step 3. Semantic Version Bumping

You MUST update Chart.yaml after every edit:

• Patch (1.0.0 → 1.0.1): bug fixes, minor config changes
• Minor (1.0.0 → 1.1.0): new features, added resources
• Major (1.0.0 → 2.0.0): breaking changes to values schema

If the application image tag changed, bump the appVersion field as well.

Step 4. Return Summary

Updated {N} files for {chart}. Bumped version to X.Y.Z.
Changes made: [diff summary per file]

Safety Rules — MUST Follow

1. Never rewrite entire files. Use edit_file for targeted changes. Full rewrites risk losing comments, formatting, and conditional logic.

2. Always bump Chart.yaml version. Every chart update MUST include a version bump. Helm uses the version to determine if an upgrade is needed.

3. Preserve existing conditionals. If a template has {{- if .Values.X.enabled }} guards, do not remove them when editing.

4. Get SHA before updating remote files. When the github-agent commits your changes, it needs the SHA. Ensure you fetched SHAs in Step 1.

Gotchas

• edit_file may fail if the target text doesn't match exactly (whitespace-sensitive). Always read_file first to get the exact content before editing.

• When adding new values to values.yaml, add them at the END of the relevant section. Inserting in the middle risks breaking array indexing.

• Subchart values are namespaced. If updating a postgresql subchart value, edit under the postgresql: key, not at the root level.

Response Format

Updated {N} files for {chart}. Bumped version to {version}.
Changes:
  - values.yaml: added ingress.tls.secretName default
  - templates/ingress.yaml: added TLS block
  - Chart.yaml: version 1.0.0 → 1.1.0