[Schema Consistency] 🔍 Schema Consistency Check - Security & Type Safety Audit (2025-10-25)

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🔍 Schema Consistency Check - Security & Type Safety Audit

Date: October 25, 2025
Run: #6
Strategy: NEW - Security-Sensitive Field & Type Coercion Audit

Executive Summary

• Inconsistencies Found: 6 critical issues
• New Issue Classes: Type coercion bypass, security warning inconsistency
• Strategy Type: New experimental strategy (30% selection path)
• Effectiveness: Very High - discovered bugs invisible to field enumeration strategies
• Risk Level: HIGH - Type safety bug in bash tool handling

🚨 Critical Issues

1. Type Coercion Bug: Boolean bash handling bypasses schema validation

Severity: 🔴 HIGH - Security & Type Safety
Location: pkg/workflow/claude_tools.go:53-59

Problem: The schema defines bash tool as accepting null | boolean | array, but the code treats ANY non-array value as "allow all commands":

if bashCommands, ok := bashTool.([]any); ok {
    claudeAllowed["Bash"] = bashCommands
} else {
    claudeAllowed["Bash"] = nil // Allow all bash commands
}

Impact:

• bash: false probably doesn't disable the tool (needs testing)
• Invalid types (e.g., bash: "string") are silently treated as "allow all"
• Schema validation is bypassed at runtime
• Security risk: misconfiguration treated as maximally permissive

Schema says:

{
  "oneOf": [
    {"type": "null"},
    {"type": "boolean", "description": "true allows all, false disables"},
    {"type": "array"}
  ]
}

Recommendation: Add explicit type checking with switch statement:

switch v := bashTool.(type) {
case []any:
    claudeAllowed["Bash"] = v
case bool:
    if v {
        claudeAllowed["Bash"] = nil // allow all
    }
    // else: don't add to allowed (disabled)
case nil:
    claudeAllowed["Bash"] = nil // allow all
default:
    return fmt.Errorf("bash tool: invalid type %T", v)
}

---

2. Missing Secret Validation: github-token accepts plaintext

Severity: 🟠 HIGH - Security
Location: Schema definition, no compile-time validation

Problem: The schema allows any string for github-token, with no pattern validation:

{
  "type": "string",
  "description": "GitHub token expression..."
}

Risk: Users could accidentally commit secrets:

github-token: ghp_actualSecretInPlainText  # 😱 LEAKED!

Recommendation: Add pattern validation or compile-time warning:

{
  "type": "string",
  "pattern": "^\\$\\{\\{.*secrets\\..*\\}\\}$",
  "description": "...",
  "examples": ["${{ secrets.GITHUB_TOKEN }}"]
}

Or add compile-time check that warns if value doesn't look like a secret expression.

---

3. Missing Security Warnings: High-privilege permissions

Severity: 🟡 MEDIUM - Documentation & Security
Locations: Schema descriptions, documentation

Problem: No security warnings for dangerous permissions:

• permissions: write-all - grants write to ALL GitHub API scopes
• No warning when combining read-all with write-enabled tools (bash)
• No security best practices section
• No audit logging recommendations

Comparison: Network firewall has EXCELLENT security validation:

• ✅ Warns when firewall disabled with restrictions (pkg/workflow/engine_firewall_support.go:84)
• ✅ Error in strict mode for misconfigurations
• ✅ Clear security messaging

Permissions validation is correct but basic:

• ✅ Validates enum values correctly
• ❌ No security warnings for write-all
• ❌ No strict mode additional checks

Recommendation: Add security warnings in schema and docs:

permissions: write-all  # ⚠️ SECURITY: Grants write access to ALL GitHub API scopes
                        # Use granular permissions in production

---

4. Missing Security Documentation: MCP external process execution

Severity: 🟡 MEDIUM - Documentation
Location: Schema $defs.stdio_mcp_tool.command

Current description:

{
  "type": "string",
  "description": "Command for stdio MCP connections"
}

Issue: No warning that this executes arbitrary external processes with access to workflow environment.

Recommendation:

{
  "type": "string",
  "description": "Command for stdio MCP connections. ⚠️ SECURITY: This executes an external process with access to the workflow environment. Only use trusted MCP servers. Command runs in isolated container (if network.firewall enabled)."
}

Similarly for http_mcp_tool.url - needs warning about external network access.

---

5. Inconsistent Security Validation Patterns

Severity: 🟡 MEDIUM - Code Quality

Excellent example (Firewall):

// pkg/workflow/engine_firewall_support.go:70-103
func (c *Compiler) checkFirewallDisable(...) error {
    if networkPermissions.Firewall.Enabled {
        if hasRestrictions {
            message := "Firewall disabled but network restrictions specified..."
            if c.strictMode {
                return fmt.Errorf("strict mode: cannot disable firewall...")
            }
            fmt.Println(console.FormatWarningMessage(message))
        }
    }
}

Basic validation (Permissions):

• ✅ Validates enum values
• ❌ No warnings for dangerous values
• ❌ No strict mode enhancement

Weak validation (Bash):

• ❌ No type validation (issue rejig docs #1)
• ❌ No strict mode checks
• ❌ No wildcard warnings

Recommendation: Apply firewall validation pattern to all security-sensitive fields.

---

6. Type Validation: Edit tool type ignored

Severity: 🟢 LOW - Code Quality
Location: pkg/workflow/claude_tools.go:72-82

if editTool, hasEdit := tools["edit"]; hasEdit {
    claudeAllowed["Edit"] = nil
    // ...
    _ = editTool  // Type completely ignored
}

The tool type is extracted but never validated. Less critical than bash issue since it doesn't affect security, but shows pattern of incomplete type validation.

---

✅ Positive Findings

1. Firewall Validation is Exemplary

The firewall security validation in pkg/workflow/engine_firewall_support.go is a gold standard example:

• Clear security warnings
• Strict mode enforcement
• Engine compatibility checking
• Helpful error messages

This pattern should be applied to other security-sensitive fields.

2. Strict Mode Provides Good Security Baseline

• 46% adoption rate (26/56 production workflows)
• Enforces important security constraints
• Well-documented in docs/src/content/docs/reference/frontmatter.md:126

Could be enhanced: Forbid bash wildcards ["*"] and write-all permissions in strict mode.

3. Production Workflows Are Secure

Real-world analysis of 56 workflows:

• ✅ 0 workflows use write-all permissions
• ✅ 0 command conflicts detected
• ✅ 4 use read-all, others use granular permissions
• ✅ Proper use of network ecosystem identifiers

Risk assessment: Production workflows follow good practices, but schema/code gaps could cause issues in new workflows.

4. Token Precedence Well-Defined

pkg/workflow/github_token.go has excellent documentation:

• Clear precedence: custom > toplevel > default
• Explains Copilot token requirements
• Good code comments

Only missing: Runtime validation (issue #2).

---

📊 Schema vs Code vs Docs Analysis

Type Coercion Matrix

Field	Schema Type	Code Accepts	Validation	Issue
tools.bash	null|boolean|array	any	❌ None	Treats any non-array as "allow all"
tools.edit	Not explicit	any	❌ None	Type completely ignored
network.firewall	null|boolean|string|object	Correctly validated	✅ Strong	Good example
permissions	string|object	Correctly validated	✅ Basic	Enum validated, no security warnings

Security Validation Matrix

Field	Schema Warnings	Code Validation	Docs	Rating
network.firewall	✅ Good	✅ Excellent	✅ Good	🟢 Exemplary
permissions	❌ None	✅ Basic	⚠️ Minimal	🟡 Adequate
tools.bash	⚠️ Minimal	❌ Weak	❌ None	🔴 Needs Work
github-token	❌ None	❌ None	⚠️ Basic	🔴 Needs Work
mcp.command	❌ None	✅ Basic	❌ None	🟡 Needs Work

---

🔧 Recommendations

HIGH PRIORITY (Security & Correctness)

1. Fix bash boolean type coercion (pkg/workflow/claude_tools.go:53-59)

   • Add explicit type switch
   • Handle false to disable tool
   • Reject invalid types
   • Add unit tests for all type cases

2. Add github-token secret validation

   • Option A: Schema pattern validation
   • Option B: Compile-time warning if not expression
   • Prevent accidental secret leakage

3. Add MCP security warnings

   • Update schema descriptions for stdio_mcp_tool.command
   • Update schema descriptions for http_mcp_tool.url
   • Document security model in MCP guide

MEDIUM PRIORITY (Security Hardening)

4. Add permissions security warnings

   • Schema description for write-all
   • Documentation section on permission security
   • Examples of granular permissions

5. Extend strict mode

   • Forbid bash: ["*"] wildcards
   • Forbid permissions: write-all
   • Require explicit permission declarations

6. Standardize security validation

   • Apply firewall validation pattern to permissions
   • Apply firewall validation pattern to bash
   • Consistent warning/error messaging

LOW PRIORITY (Documentation & Polish)

7. Create security reference documentation

   • Comprehensive security model explanation
   • Best practices for production workflows
   • Audit logging recommendations

8. Improve type validation across all tools

   • Validate edit tool configuration
   • Add type checks for all tool configs
   • Better error messages for type mismatches

---

📁 Files Requiring Updates

Schema Changes

• pkg/parser/schemas/main_workflow_schema.json
  • Add security warnings to descriptions
  • Add github-token pattern validation
  • Enhance MCP tool descriptions

Code Changes

• pkg/workflow/claude_tools.go:53-59 - Fix bash boolean handling
• pkg/workflow/permissions.go - Add security warnings for write-all
• pkg/workflow/github_token.go - Add secret reference validation
• pkg/workflow/strict_mode.go - Add wildcard and write-all checks

Documentation Changes

• docs/src/content/docs/reference/frontmatter.md - Add security warnings
• docs/src/content/docs/reference/tools.md - Add bash security section
• docs/src/content/docs/guides/security.md - Expand best practices
• docs/src/content/docs/guides/mcps.md - Add security implications

---

🎯 Strategy Performance

Strategy Name: Security-Sensitive Field & Type Coercion Audit
Strategy ID: strategy-006

Findings: 6 critical issues
New Issue Classes: 2 (type coercion, security warning gaps)
Effectiveness: ⭐⭐⭐⭐⭐ VERY HIGH

Why This Strategy Worked:

1. Security lens reveals issues invisible to field enumeration
2. Type coercion testing finds schema bypass bugs
3. Comparing validation patterns shows inconsistency
4. Real-world usage analysis validates risk assessment

Unique Contributions:

• Found type safety bug (bash boolean handling)
• Identified security warning gaps
• Revealed validation pattern inconsistency
• Highlighted firewall as gold standard example

Comparison to Previous Strategies:

Strategy	Focus	Findings	Overlap
#2: Enum validation	Enum values	12	Reaction enum (fixed)
#3: Required fields	Error messages	8	Documentation gaps
#4: Cross-schema	Schema consistency	5	MCP definitions
#5: Conditional logic	Field relationships	11	Feature interactions
#6: Security audit	Type safety & security	6	NEW class of issues

Recommendation: Use every 4-5 runs, alternating with strategy-005. Complements all other strategies with security perspective.

---

🔄 Cache Strategy Performance

Total Runs: 6
Total Findings: 50
Average per Run: 8.3
Critical Issues: 22
Documentation Gaps: 26

Most Effective: Strategy-002 (Enum Validation) - 12 findings
Most Complementary: Strategy-006 (Security Audit) - unique perspective
Best for Production: Strategy-003 (Error Messages) + Strategy-006 (Security)

Strategy Selection Process:

• Day of year: 298
• Selection value: 298 mod 10 = 8
• Result: NEW strategy (values 7-9)
• ✅ Successfully discovered new issue class

---

📈 Next Run Suggestions

For the next run, recommended strategies:

70% Proven Strategy Pool:

1. Strategy-002 (Enum Validation) - Most comprehensive
2. Strategy-005 (Conditional Logic) - Feature interactions
3. Strategy-003 (Required Fields) - Error documentation

30% New Strategy Pool:

1. Deprecation audit - Check warning messages and migration paths
2. Error message quality - Assess clarity and helpfulness
3. Example validation - Validate all doc examples against schema

Next Security Review: Run Strategy-006 again in 4-5 runs to check if recommendations implemented.

---

🔗 Related Issues

This analysis builds on previous findings:

• Previous runs identified missing documentation for imports, mcp-servers
• Strategy-002 found and fixed reaction enum validation
• Strategy-005 documented conditional requirements extensively

This run focuses specifically on security posture and type safety - a dimension not covered by previous strategies.

---

📝 Detailed Analysis Report

Full technical analysis saved to: /tmp/gh-aw/cache-memory/security_analysis_2025-10-25.md

Strategy database updated: /tmp/gh-aw/cache-memory/strategies.json

AI generated by Schema Consistency Checker

[pelikhan]

/plan

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