Commit Methods

Modality contracts are append-only logs of commits. Each commit contains one or more actions, and each action has a method that determines what it does.

POST

The most common method - writes data to a path in the contract state.

{
  "method": "post",
  "path": "/users/alice.id",
  "value": "12D3KooWAbCdEfGhIjKlMnOpQrStUvWxYz..."
}

Path Types

Paths must end with a known extension:

Extension	Type	Example Value
.bool	Boolean	true or false
.text	Text string	"Hello world"
.date	Date	"2024-01-15"
.datetime	Date and time	"2024-01-15T10:30:00Z"
.json	JSON object	{"key": "value"}
.md	Markdown	"# Title\n\nContent..."
.id	Modality ID	"12D3KooW..."
.wasm	WebAssembly	Base64-encoded WASM
.modality	Rules/formulas	Modality syntax

RULE

Adds a temporal logic constraint to the contract. Rules are accumulated over time and all must be satisfied.

{
  "method": "rule",
  "path": "/rules/auth.modality",
  "value": "always ([<+signed_by(/users/alice.id)>] true)"
}

Rules must have paths ending in .modality.

REPOST

Copies data from another contract into a local namespace. This enables cross-contract data sharing while maintaining clear provenance.

{
  "method": "repost",
  "path": "$abc123def:/announcements/latest.text",
  "value": "Hello from the other contract!"
}

Path Format

REPOST paths use a special namespace format:

$<source_contract_id>:/<remote_path>

• $ - Indicates this is reposted (external) data
• <source_contract_id> - The contract ID where the data originated
• : - Separator
• /<remote_path> - The original path in the source contract

Local Storage

Reposted data is stored locally in the reposts/ directory:

reposts/
  <contract_id>/
    <path>/
      file.ext

CLI Usage

# Repost data from another contract
modal contract repost \
  --from-contract abc123def456 \
  --from-path /announcements/latest.text \
  --value "The announcement content"

# With custom destination path
modal contract repost \
  --from-contract abc123def456 \
  --from-path /data/config.json \
  --to-path '$abc123def456:/imported/config.json' \
  --value '{"setting": "value"}'

# Signed repost
modal contract repost \
  --from-contract abc123def456 \
  --from-path /messages/hello.text \
  --value "Hello!" \
  --sign alice.passfile

Use Cases

1. Cross-contract references: Include data from one contract in another's state
2. Data mirroring: Keep a local copy of important external data
3. Audit trails: Track the provenance of imported data
4. Agent coordination: Share information between contracts managed by different agents

CREATE

Creates a new asset in the contract.

{
  "method": "create",
  "value": {
    "asset_id": "token1",
    "quantity": 21000000,
    "divisibility": 100000000
  }
}

SEND

Sends assets to another contract.

{
  "method": "send",
  "value": {
    "asset_id": "token1",
    "to_contract": "target_contract_id",
    "amount": 1000
  }
}

RECV

Receives assets from a SEND in another contract.

{
  "method": "recv",
  "value": {
    "send_commit_id": "abc123..."
  }
}

INVOKE

Executes a WASM program stored in the contract.

{
  "method": "invoke",
  "path": "/__programs__/calculator.wasm",
  "value": {
    "args": {
      "operation": "add",
      "a": 5,
      "b": 3
    }
  }
}