Secret Handling Agent Skill

Context

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.

Patterns

Prohibited File Reads

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)
• Any file matching .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:

• Ask the user directly — "What's the database connection string?"
• Read .env.example — shows structure without exposing secrets
• Read documentation — check README.md, docs/, config guides

NEVER assume you can "just peek at .env to understand the schema." Use .env.example or ask.

Prohibited Output Patterns

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:

• Placeholder values: DATABASE_URL=<set in .env>
• Redacted references: API key configured (see .env.example)
• Architecture notes: "App uses JWT auth — token stored in session"
• Schema documentation: "Requires OPENAI_API_KEY, GITHUB_TOKEN (see .env.example for format)"

Scribe Pre-Commit Validation

Before committing .squad/ changes, Scribe MUST:

• Scan all staged files for secret patterns (use regex table above)
• Check for prohibited file names (don't commit .env even if manually staged)
• If secrets detected:
• STOP the commit (do NOT proceed)
• Remove the file from staging: git reset HEAD <file>
• Report to user:

     🚨 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.

• Exit with error (never silently skip)

• If no secrets detected:
• Proceed with commit as normal

Implementation note for Scribe:

• Run validation AFTER staging files, BEFORE calling git commit
• Use PowerShell Select-String or git diff --cached to scan staged content
• Fail loud — secret leaks are unacceptable, blocking the commit is correct behavior

Remediation — If a Secret Was Already Committed

If you discover a secret in git history:

• STOP immediately — do not make more commits
• Alert the user:

   🚨 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.

• Do NOT attempt to fix it yourself — secret removal requires specialized tools
• Wait for user confirmation before resuming work

Examples

✓ Correct: Reading Config Schema

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."

✗ Incorrect: Reading Live Credentials

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/."

✓ Correct: Scribe Pre-Commit Validation

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

Anti-Patterns

• ❌ Reading .env "just to check the schema" — use .env.example instead
• ❌ Writing "sanitized" connection strings that still contain credentials
• ❌ Assuming "it's just a dev environment" makes secrets safe to commit
• ❌ Committing first, scanning later — validation MUST happen before commit
• ❌ Silently skipping secret detection — fail loud, never silent
• ❌ Trusting agents to "know better" — enforce at multiple layers (prompt, hook, architecture)
• ❌ Writing secrets to "temporary" files in .squad/ — Scribe commits ALL .squad/ changes
• ❌ Extracting "just the host" from a connection string — still leaks infrastructure topology