Phase 0 — Branch & Foundation

Phase 0 — Branch & Foundation

Context Load

Read these files before starting:

1. docs/tf-support/PROGRESS.md — verify Phase 0 is active and which items remain
2. .devcontainer/devcontainer.json — current state (understand before editing)
3. .gitignore — current state
4. .gitattributes — current state (if it exists)
5. .vscode/mcp.json — current MCP server config
6. package.json — current devDependencies and scripts

Phase 0 Deliverables

Work through unchecked items in order. Skip already-checked items.

Item 0.1 — tf-dev branch

Check: git branch --show-current. If already on tf-dev, mark done and skip.

Item 0.2 — devcontainer Terraform + Go features

Edit .devcontainer/devcontainer.json — add to the features block:

"ghcr.io/devcontainers/features/terraform:1": {
  "installTFsec": true
},
"ghcr.io/devcontainers/features/go:1": {}

Add to containerEnv:

"TF_PLUGIN_CACHE_DIR": "/home/vscode/.terraform.d/plugin-cache"

Add to customizations.vscode.settings:

"[terraform]": {
  "editor.tabSize": 2,
  "editor.formatOnSave": true,
  "editor.defaultFormatter": "hashicorp.terraform"
}

Item 0.3 — devcontainer extensions

Add to customizations.vscode.extensions:

"HashiCorp.terraform",
"ms-azuretools.vscode-azureterraform"

Item 0.4 — .gitignore

Add after existing cloud/IDE ignores:

# Terraform
*.tfstate
*.tfstate.backup
.terraform/
*.tfvars
!terraform.tfvars.example
crash.log
crash.*.log
.infracost/
# DO NOT ignore .terraform.lock.hcl — it must be committed for reproducible provider versions

Item 0.5 — .gitattributes

If .gitattributes does not exist, create it. Add:

*.tf      linguist-language=HCL
*.tfvars  linguist-language=HCL
*.hcl     linguist-language=HCL

Item 0.6 — MCP server + devDependency

Edit .vscode/mcp.json — add a new server entry:

"terraform": {
  "type": "stdio",
  "command": "npx",
  "args": ["-y", "@hashicorp/terraform-mcp-server"],
  "env": {}
}

Edit package.json — add to devDependencies:

"@hashicorp/terraform-mcp-server": "latest"

Then run: npm install to install the new devDependency.

Item 0.7 — infra/terraform/

mkdir -p infra/terraform
touch infra/terraform/.gitkeep

Item 0.8 — MCP Tool Verification (GATE)

This item blocks Phase 2. After restarting VS Code and reloading MCP servers:

1. Use tool_search_tool_regex with pattern terraform|hashicorp to enumerate the actual tool names exposed by the HashiCorp MCP server.
2. Create docs/tf-support/mcp-tools.md with the verified tool names. Format: table with Tool Name, Purpose, Equivalent (if any).
3. If no module lookup tools exist, document the fallback: Terraform Registry API at registry.terraform.io/v1/modules/Azure/{module}/azurerm/versions

Note: Items 2.15, 2.16, 2.17 (agent frontmatter tools: lists) cannot be finalized until this gate is complete. Continue with Phase 1 while waiting if VS Code cannot be restarted now.

Validation

npm run validate:all

Expected: all existing validators pass. No Terraform-specific validators yet.

Commit

git add .devcontainer/ .gitignore .gitattributes .vscode/mcp.json package.json package-lock.json infra/terraform/.gitkeep docs/tf-support/mcp-tools.md
git commit -m "feat(devcontainer): add Terraform toolchain, MCP server, and git config

- Add Terraform + tfsec devcontainer feature
- Add Go feature for future Terratest
- Add HashiCorp.terraform and vscode-azureterraform extensions
- Add Terraform gitignore entries (commit .terraform.lock.hcl)
- Add HCL linguist attributes
- Add @hashicorp/terraform-mcp-server to mcp.json (npx)
- Pre-install @hashicorp/terraform-mcp-server as devDependency
- Scaffold infra/terraform/ directory"

Update PROGRESS.md

After committing, update docs/tf-support/PROGRESS.md:

1. Check off each completed item (- [x])
2. Update Phase 0 row in the status table: Done count + Status → ✅ Complete or 🔄 In Progress
3. If 0.8 is pending (VS Code restart needed), set Status = 🔄 In Progress and add a Blockers row
4. Update frontmatter: active_phase: 1 if all 8 items done; last_session = today's date
5. Add a row to Blockers & Notes: date, your name, items completed
6. Commit: git add docs/tf-support/PROGRESS.md && git commit -m "chore(progress): complete Phase 0"