Sync Documentation

Overview

Ensure documentation is synchronized across all key files when variables or features change.

Usage

/sync-docs

Documentation Files

Workflow

digraph sync_flow {
    rankdir=TB;
    node [shape=box];

    extract [label="1. Extract from variables.tf"];
    compare [label="2. Compare with docs/llms.md"];
    gaps [label="3. Identify gaps"];
    update_llms [label="4. Update docs/llms.md"];
    update_example [label="5. Update kube.tf.example"];
    update_readme [label="6. Update README if needed"];
    verify [label="7. Verify consistency"];

    extract -> compare;
    compare -> gaps;
    gaps -> update_llms;
    update_llms -> update_example;
    update_example -> update_readme;
    update_readme -> verify;
}

Step 1: Extract Variables from Source

Use exact extraction before semantic review:

# List all variables from variables.tf
rg -o '^variable "[^"]+"' variables.tf | cut -d'"' -f2 | sort -u

# Get variable details
sed -n '/^variable "<name>"/,/^}/p' variables.tf

Step 2: Find Undocumented Variables

# Compare source variable names with code-formatted names in docs/llms.md
comm -23 \
  <(rg -o '^variable "[^"]+"' variables.tf | cut -d'"' -f2 | sort -u) \
  <(rg -o '`[a-zA-Z_][a-zA-Z0-9_]*`' docs/llms.md | tr -d '`' | sort -u)

Step 3: Generate Documentation

docs/llms.md Format

**Variable Name**

```tf
variable_name = "default_value"

• variable_name (Type, Optional/Required):
  • Default: default_value
  • Purpose: Clear explanation of what this does
  • Usage: When and how to use it
  • Considerations: Important notes, limitations, impacts
  • Example: Practical usage example if helpful

### kube.tf.example Format

```tf
  # Description of what this controls
  # Additional context if needed
  # variable_name = "default_value"

Step 4: Update docs/llms.md

For each undocumented variable:

1. Read variable definition from variables.tf
2. Understand its usage in locals.tf and other files
3. Write comprehensive documentation following the format above
4. Place in appropriate section of docs/llms.md

Section Organization in docs/llms.md

Step 5: Update kube.tf.example

Ensure new variables appear in the example with:

• Clear comment explaining purpose
• Commented out with default value
• Grouped with related variables

# Inspect source variables that do not appear in kube.tf.example
comm -23 \
  <(rg -o '^variable "[^"]+"' variables.tf | cut -d'"' -f2 | sort -u) \
  <(rg -o '[a-zA-Z_][a-zA-Z0-9_]*[[:space:]]*=' kube.tf.example | sed 's/[[:space:]]*=//' | sort -u)

Step 6: Update README if Needed

Update README.md if:

• New major feature added
• New CNI or ingress option
• Significant capability change

README is the visual project entry point, four-step Quick Start, and documentation router. Keep the running-cluster image in the opening block and keep README at or below the contract limit enforced by scripts/tests/test_generated_site_contract.sh. Put debugging, upgrade, day-2 operations, long support notes, and advanced recipes in their focused guides; add or update the route in docs/index.md instead of growing README.

When moving README content, keep repository-relative links valid from the new directory depth and regenerate site-docs/index.md with python3 scripts/sync_docs_site.py. The generator rewrites extracted README links for the site-docs/ directory; verify them with the generated-site contract test.

Features section should match actual capabilities.

For Tailscale changes, keep these surfaces in sync:

• docs/support-matrix.md support levels and docs/recipes/networking-and-scale.md Tailscale recipe
• kube.tf.example Tailscale node-transport comments
• docs/llms.md support levels and variable notes
• docs/v3-topology-recommendations.md
• examples/tailscale-node-transport/README.md
• examples/external-overlay-tailscale/README.md
• examples/external-overlay-cloudflare-access/README.md when access-boundary wording changes
• .claude/skills/kh-assistant/SKILL.md
• .claude/skills/migrate-v2-to-v3/SKILL.md

For Cloudflare Zero Trust wording, keep the boundary consistent:

• Cloudflare Access/Tunnel is a documented external operator/app access pattern.
• kube-hetzner does not add Cloudflare provider inputs or manage Cloudflare resources.
• Cloudflare Mesh/WARP is not supported kube-hetzner node transport in v3.
• Tailscale remains the supported managed node transport for secure multinetwork scale.

For Cilium Gateway API changes, keep these surfaces in sync:

• variables.tf validation for cilium_gateway_api_enabled
• locals.tf Cilium values and Gateway API CRD version mapping
• README.md
• kube.tf.example
• docs/llms.md
• docs/v3-topology-recommendations.md
• examples/cilium-gateway-api/README.md
• .claude/skills/kh-assistant/SKILL.md
• .claude/skills/test-changes/SKILL.md

For embedded registry mirror changes, keep these surfaces in sync:

• variables.tf validation for embedded_registry_mirror
• locals.tf effective generated registries YAML merge behavior
• host/control-plane/agent/autoscaler config rendering
• README.md
• kube.tf.example
• docs/llms.md
• docs/v3-topology-recommendations.md
• .claude/skills/kh-assistant/SKILL.md
• .claude/skills/test-changes/SKILL.md

For v2 -> v3 migration or production-upgrade safety changes, keep these surfaces in sync:

• MIGRATION.md, especially "Production in-place upgrades: safety model"
• docs/v2-to-v3-migration.md
• CHANGELOG.md upgrade notes
• docs/v3-release-evidence.md live proof
• .claude/skills/migrate-v2-to-v3/SKILL.md
• .claude/skills/upgrade-cluster/SKILL.md
• .claude/skills/kh-assistant/SKILL.md

The no-destroy gate must include the full protected hcloud set: hcloud_server, hcloud_network, hcloud_network_subnet, hcloud_load_balancer, hcloud_volume, hcloud_primary_ip, hcloud_placement_group, and hcloud_firewall.

For SELinux changes, keep these surfaces in sync:

• docs/selinux.md
• templates/kube-hetzner-selinux.te
• templates/k8s-custom-policies.te
• variables.tf enable_selinux and per-pool selinux
• .claude/skills/debug-node/SKILL.md
• .claude/skills/kh-assistant/SKILL.md

Do not make generic "disable SELinux" recommendations. The operator path is AVC evidence, udica-first workload policy, upstream module policy only with reproducible denials, and per-pool selinux = false as the last resort.

For release presentation changes, verify README's compact current-release link points at the latest release tag and that CHANGELOG.md contains the release content.

Step 7: Verify Consistency

Run the exact comparisons above, terraform-docs, the generated-site contract, and the relevant validators from /test-changes. Then inspect defaults and descriptions for each changed variable directly in all three surfaces.

Verification Checklist

• All variables.tf variables documented in docs/llms.md
• All major variables appear in kube.tf.example
• README features match actual capabilities
• No typos in variable names across files
• Default values consistent across docs
• Major-upgrade safety wording matches MIGRATION.md
• SELinux workload-denial wording points to docs/selinux.md
• README current-release URL is current for the release train

Common Sync Issues

Variable renamed

1. Update in variables.tf
2. Search and replace in docs/llms.md
3. Search and replace in kube.tf.example
4. Add to CHANGELOG.md (breaking change!)

Variable removed

1. Remove from variables.tf
2. Remove from docs/llms.md
3. Remove from kube.tf.example
4. Add to CHANGELOG.md (breaking change!)

Default changed

1. Update in variables.tf
2. Update in docs/llms.md
3. Update in kube.tf.example
4. Consider if this is a breaking change

Quick Commands

# Regenerate terraform docs
terraform-docs markdown table --config .terraform-docs.yml \
  --output-mode inject --output-file docs/terraform.md .

# Validate v3 topology/Gateway/registry surfaces
uv run scripts/validate_v3_final_polish_examples.py

# Validate rendered templates and negative contract cases when those surfaces change
uv run scripts/render_harness.py
uv run scripts/contract_negative_tests.py

# Search for variable across all docs
rg -n "variable_name" docs/ kube.tf.example README.md

# Find undocumented variables (quick check)
diff <(rg -o 'variable "([^"]+)"' -r '$1' variables.tf | sort) \
     <(rg -o '`[a-z_]+`' docs/llms.md | tr -d '`' | sort -u) | rg "^<"

After Sync

1. Run terraform fmt -recursive
2. Commit only if the current task calls for a commit, with message: docs: sync documentation with variables.tf
3. If breaking changes, update CHANGELOG.md