microsoft/generative-ai-for-beginners-dotnet-secret-handling
Never read .env files or write secrets to .squad/ committed files
npx skills add https://github.com/microsoft/Generative-AI-for-beginners-dotnet --skill secret-handling
Spawned agents have read access to the entire repository, including .env files containing live credentials. If an agent reads secrets and writes them to .squad/ files (decisions, logs, history), Scribe auto-commits them to git, exposing them in remote history. This skill codifies absolute prohibitions and safe alternatives.
NEVER read these files:
.env (production secrets).env.local (local dev secrets).env.production (production environment).env.development (development environment).env.staging (staging environment).env.test (test environment with real credentials).env.* UNLESS explicitly allowed (see below)Allowed alternatives:
.env.example (safe — contains placeholder values, no real secrets).env.sample (safe — documentation template).env.template (safe — schema/structure reference)If you need config info:
.env.example — shows structure without exposing secretsREADME.md, docs/, config guidesNEVER assume you can "just peek at .env to understand the schema." Use .env.example or ask.
NEVER write these to .squad/ files:
| Pattern Type | Examples | Regex Pattern (for scanning) |
|--------------|----------|-------------------------------|
| API Keys | OPENAI_API_KEY=sk-proj-..., GITHUB_TOKEN=ghp_... | [A-Z_]+(?:KEY|TOKEN|SECRET)=[^\s]+ |
| Passwords | DB_PASSWORD=super_secret_123, password: "..." | (?:PASSWORD|PASS|PWD)[:=]\s*["']?[^\s"']+ |
| Connection Strings | postgres://user:pass@host:5432/db, Server=...;Password=... | (?:postgres|mysql|mongodb)://[^@]+@|(?:Server|Host)=.*(?:Password|Pwd)= |
| JWT Tokens | eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9... | eyJ[A-Za-z0-9_-]+\.eyJ[A-Za-z0-9_-]+\.[A-Za-z0-9_-]+ |
| Private Keys | -----BEGIN PRIVATE KEY-----, -----BEGIN RSA PRIVATE KEY----- | -----BEGIN [A-Z ]+PRIVATE KEY----- |
| AWS Credentials | AKIA..., aws_secret_access_key=... | AKIA[0-9A-Z]{16}|aws_secret_access_key=[^\s]+ |
| Email Addresses | [email protected] (PII violation per team decision) | [a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,} |
What to write instead:
DATABASE_URL=<set in .env>API key configured (see .env.example)Before committing .squad/ changes, Scribe MUST:
.env even if manually staged)git reset HEAD <file> 🚨 SECRET DETECTED — commit blocked
File: .squad/decisions/inbox/river-db-config.md
Pattern: DATABASE_URL=postgres://user:password@localhost:5432/prod
This file contains credentials and MUST NOT be committed.
Please remove the secret, replace with placeholder, and try again.
Implementation note for Scribe:
git commitSelect-String or git diff --cached to scan staged contentIf you discover a secret in git history:
🚨 CREDENTIAL LEAK DETECTED
A secret was found in git history:
Commit: abc1234
File: .squad/decisions/inbox/agent-config.md
Pattern: API_KEY=sk-proj-...
This requires immediate remediation:
1. Revoke the exposed credential (regenerate API key, rotate password)
2. Remove from git history (git filter-repo or BFG)
3. Force-push the cleaned history
Do NOT proceed with new work until this is resolved.
Agent needs to know what environment variables are required:
Agent: "What environment variables does this app need?"
→ Reads `.env.example`:
OPENAI_API_KEY=sk-...
DATABASE_URL=postgres://user:pass@localhost:5432/db
REDIS_URL=redis://localhost:6379
→ Writes to .squad/decisions/inbox/river-env-setup.md:
"App requires three environment variables:
- OPENAI_API_KEY (OpenAI API key, format: sk-...)
- DATABASE_URL (Postgres connection string)
- REDIS_URL (Redis connection string)
See .env.example for full schema."
Agent needs to know database schema:
Agent: (reads .env)
DATABASE_URL=postgres://admin:[email protected]:5432/appdb
→ Writes to .squad/decisions/inbox/river-db-schema.md:
"Database connection: postgres://admin:[email protected]:5432/appdb"
🚨 VIOLATION: Live credential written to committed file
Correct approach:
Agent: (reads .env.example OR asks user)
User: "It's a Postgres database, schema is in migrations/"
→ Writes to .squad/decisions/inbox/river-db-schema.md:
"Database: Postgres (connection configured in .env). Schema defined in db/migrations/."
Scribe is about to commit:
# Stage files
git add .squad/
# Scan staged content for secrets
$stagedContent = git diff --cached
$secretPatterns = @(
'[A-Z_]+(?:KEY|TOKEN|SECRET)=[^\s]+',
'(?:PASSWORD|PASS|PWD)[:=]\s*["'']?[^\s"'']+',
'eyJ[A-Za-z0-9_-]+\.eyJ[A-Za-z0-9_-]+\.[A-Za-z0-9_-]+'
)
$detected = $false
foreach ($pattern in $secretPatterns) {
if ($stagedContent -match $pattern) {
$detected = $true
Write-Host "🚨 SECRET DETECTED: $($matches[0])"
break
}
}
if ($detected) {
# Remove from staging, report, exit
git reset HEAD .squad/
Write-Error "Commit blocked — secret detected in staged files"
exit 1
}
# Safe to commit
git commit -F $msgFile
.env "just to check the schema" — use .env.example instead.squad/ — Scribe commits ALL .squad/ changesTake microsoft/generative-ai-for-beginners-dotnet-secret-handling from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.