read

eth_call a view function. With assert: it becomes a hard gate; without, it's enrichment for later steps.

- id: gate
  read:
    contract: USDC
    network: base
    function: "balanceOf(address)"
    args: ["${{ relayers.payout.address }}"]
    assert: "${{ output >= trigger.args.value }}"

Fields

Field	Required	Description
`contract`	✅	A contract registry name
`network`	✅	A declared network
`function`	✅	Solidity signature, e.g. `balanceOf(address)`
`args`		Arguments — each may be an expression
`assert`		Expression over the decoded `output` — false fails the step with kind `assert_failed`
`on_error`	`fail`	`fail` \| `continue` — see below

Output

The decoded return values become steps.<id>.output:

a single return value is unwrapped: balanceOf → steps.gate.output is the balance itself
multiple return values become a map keyed by ABI output names (positional when unnamed)

uint256 outputs stay exact — compare and do math on them directly, see U256 semantics.

assert — the gate

The assert: expression sees output alongside the full run context:

assert: "${{ output >= trigger.args.value and output > wei('1', 6) }}"

A false assert fails the step with kind assert_failed — a deliberate stop, never retried. The run then follows on_failure.

on_error: continue — soft enrichment

By default a failed read (RPC error, revert, false assert) fails the step. Set on_error: continue to turn it into soft enrichment instead: the step succeeds with output: null and the run continues.

- id: price
  read:
    contract: Oracle
    network: ethereum
    function: "latestAnswer()"
    on_error: continue     # nice-to-have, not load-bearing