Meta-Properties

Each sub-VM carries VM meta-properties. Some are part of the startup message; others are VM-internal. This page defines those fields; how they are derived when a sub-VM starts is specified in Sub-VM Creation.

Most permission meta-properties are granted by the node for the initial entry. The exception is can_use_balance_for_message_fees, which is owned by the contract: it is stored in the contract’s root slot and read before execution begins.

Execution Meta-Properties

stack

Startup-message field containing the view-call stack of contract addresses.

depth

Internal field containing the nesting depth of the sub-VM.

permissions

Internal field containing the permission meta-properties granted to the sub-VM.

state_mode

Internal field selecting the storage view used by reads (a storage_type).

topmost_runner_id

Internal field selecting the entry runner for this sub-VM.

det_subvm_hashes

Internal accumulator for deterministic child sub-VM result hashes; see Sub-VM Result Hash.

granted_custom

Internal field containing custom runners granted to this sub-VM at startup; see Custom-Runner Grants.

Custom runners are not permission meta-properties: they are tracked by the sub-VM’s loaded-runner set (Custom Runner Loading) and by this field.

Permission Meta-Properties

deterministic

When true, the sub-VM executes in Deterministic Mode. Storage writes, message sends, contract calls, event emission, and runner registration require this meta-property where specified below.

write_storage

Allows writing contract storage slots. Requires deterministic.

This meta-property also gates EmitEvent: a sub-VM may emit events iff it can write storage.

send_messages

Allows sending messages to other addresses. Required by EthSend, PostMessage, and DeployContract. Requires deterministic.

call_others

Allows calling other contracts. Required by EthCall and CallContract Message. Requires deterministic.

spawn_nondet

Allows spawning Non-Deterministic Mode sub-VM instances via RunNondet Message.

register_runners

Allows registering runner archives at runtime via RegisterRunner Message. Requires deterministic.

can_use_balance_for_message_fees

Allows the contract to draw on its own balance to pay fees for outgoing internal messages (PostMessage, DeployContract). The flag has no effect on external EthSend messages.

Unlike the meta-properties above, this one is stored as a bit in the root slot’s inline permissions bitfield and read before execution begins. The bit offset is the corresponding member of permissions.