YAML Master

Proactive YAML intelligence: validate syntax, enforce consistent formatting, and keep configuration files schema-correct (Kubernetes, GitHub Actions, Docker Compose, and similar).

Overview

This skill activates when working with .yml /.yaml files to detect structural issues early (indentation, anchors, type mismatches), and to produce safe, minimal edits that keep CI/config tooling happy.

Prerequisites

• The YAML file(s) to inspect and their intended target (e.g., Kubernetes, GitHub Actions, Compose)

• Any relevant schema or constraints (when available)

• Permission to edit the file(s) (or to propose a patch)

Instructions

• Parse and validate YAML syntax (identify the first breaking error and its location).

• Normalize formatting (indentation, quoting) without changing semantics.

• Validate structure against the target system’s expectations (keys, types, required fields).

• Identify risky patterns (duplicate keys, ambiguous scalars, anchors used incorrectly).

• Output a minimal patch plus a short validation checklist (what to run next).

Output

• Corrected YAML with minimal diffs

• A concise list of issues found (syntax vs schema vs best practice)

• Follow-up validation commands appropriate for the target (e.g., kubectl apply --dry-run=client , CI lint)

Error Handling

• If the schema/target is unknown, ask for the target system and apply syntax-only fixes first.

• If the YAML is valid but tooling still fails, surface the exact downstream error and reconcile expectations.

Examples

Example: Fix an indentation/syntax error

• Input: a workflow with a mis-indented steps: block.

• Output: corrected indentation and a note on which job/step was affected.

Example: Convert JSON to YAML safely

• Input: a JSON config blob.

• Output: YAML with explicit quoting where necessary to avoid type surprises.

Resources

• Full detailed guide (kept for reference): ${CLAUDE_SKILL_DIR}/references/SKILL.full.md

• YAML spec: https://yaml.org/spec/

• GitHub Actions workflow syntax: https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions