Constitution

The constitution is Commander's safety backbone — a TOML file signed with Ed25519 that defines what the agent can and cannot do. It cannot be bypassed.

Structure

[identity]
version = "1.0.0"
checksum = "..."     # SHA-256 of content
signed_by = "..."    # Who signed it
signature = "..."    # Ed25519 signature

[boundaries]
# Never execute these (highest priority)
forbidden = [
    "rm -rf /",
    "DROP DATABASE",
    "sudo rm *",
]

# Ask before executing
requires_approval = [
    "git push",
    "deploy *",
    "install package",
]

# Execute freely
auto_allowed = [
    "git *",
    "cargo test",
    "npm test",
    "echo *",
    "cat *",
]

[resource_limits]
max_api_cost_per_run = 5.0
max_api_cost_per_day = 50.0
max_execution_time = 3600
max_concurrent_workflows = 3
max_file_write_size = "10MB"
allowed_directories = ["~/Projects", "~/.mur", "/tmp"]
blocked_directories = ["/etc", "/System", "~/.ssh"]

[model_permissions]
thinking_model = { can_execute = false, can_read = true }
coding_model = { can_execute = true, can_read = true, sandbox_only = true }
task_model = { can_execute = true, can_read = true }

How It Works

Every action goes through a 3-step check:

1. Forbidden? → Blocked immediately, logged to audit
2. Requires approval? → Paused until user confirms
3. Auto allowed? → Executes freely
4. Unknown? → Defaults to requiring approval (safe default)

Pattern matching uses word boundaries — git * matches git push but not digit.

Signing & Verification

# Generate keypair + sign
murc constitution sign

# Verify integrity
murc constitution verify

# View current rules
murc constitution show

If the constitution file is modified without re-signing, verify will detect the tampering:

VERIFICATION FAILED: Constitution has been modified!
  Expected checksum: 359c58b7...
  Actual checksum:   a1b2c3d4...

Tamper Protection

• SHA-256 checksum of the entire file (excluding identity section)
• Ed25519 signature over the checksum
• Keys stored separately (signing.key, signing.pub)
• The watchdog independently monitors constitution integrity at runtime