Error: rule_error
The rule payload failed validation. The API names the exact problem: invalid_rule_type, invalid_rule_action, invalid_rule_params, invalid_rule_priority, or invalid_rule_label.
What it means
Rules are validated when created (and when updated). A malformed rule is rejected before it can affect any transaction.
The validation error names
invalid_rule_type — unknown rule type (e.g. not per_transaction_cap, daily_ceiling, velocity_limit, merchant_allowlist, category_rule, time_of_day).
invalid_rule_action — action must be one of the supported decisions (approve / block / flag).
invalid_rule_params — parameters for the rule type are missing or out of range.
invalid_rule_priority — priority isn't a valid finite number in the accepted range.
invalid_rule_label — label is malformed or too long.
How to fix
Use one of the documented rule types and actions.
Check params against the type: a cap needs max; an allowlist needs the merchant list; a velocity rule needs count and window.
Keep labels short and plain.
At a glance
| Field | Value |
|---|---|
| HTTP status | 400 |
| Error code | rule_error (invalid_rule_type / invalid_rule_action / invalid_rule_params / invalid_rule_priority / invalid_rule_label) |
| Response shape | {"error": "invalid_rule_params"} |
| Rule stored | No |
Valid rule example
{
"type": "per_transaction_cap",
"action": "block",
"params": {"max": 500, "currency": "USD"},
"priority": 1,
"label": "Block any single transaction over $500"
}Match type, action, and params or you get a named rule_error.
FAQ
Where can I see the supported rule types?
The six enforced rule types are per-transaction cap, daily/period total, velocity limit, merchant allowlist, category rule, and time-of-day rule.
What does invalid_rule_params cover?
Missing or out-of-range parameters for the rule type — e.g. a cap without max, or a velocity rule with a negative window.
Does a bad rule affect existing rules?
No. Rejected rules are never stored; your existing rules keep enforcing.
Related
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