Invalid Formula Dependency

One formula field uses another field that is itself a formula (both values start with =). Only one layer of evaluation is supported: a formula may read literal top-level payload values (via signal.<key>), not the output of a sibling formula field.

Typical error detail (webhook log)

The formula in field b references a, which is another formula field. Chained formulas are not supported.

Here a is the top-level key that is also defined as a formula.

Incorrect

{
  "ticker": "SPY",
  "action": "buy",
  "closePrice": "450.25",
  "buffer": "=0.5",
  "limitPrice": "=signal.closePrice + signal.buffer"
}

buffer is a formula, so signal.buffer is not allowed as a dependency.

Option A — fold into a single formula

{
  "ticker": "SPY",
  "action": "buy",
  "closePrice": "450.25",
  "limitPrice": "=signal.closePrice + 0.5"
}

Option B — send the intermediate value as a literal

{
  "ticker": "SPY",
  "action": "buy",
  "closePrice": "450.25",
  "buffer": "0.5",
  "limitPrice": "=signal.closePrice + signal.buffer"
}

Option C — compute upstream

Precompute limitPrice in TradingView (or your sender) and send it as a plain number string with no leading =.

If you intended to reference a field that is not a formula but still see this message, check that the referenced key does not accidentally start with = in the JSON you send.