Config schema: rhai

This page lists the fields for the optional top-level rhai: block (sandbox limits for Rule Rhai). For what each limit means, fail-open behavior, host API costing, and safe patterns, see Sandbox limits.

rhai

Property	Value
Type	Object
Required	No — when omitted, built-in defaults still apply
Location	Top-level key in the config file or overlay (whole-section replace)

Field	Type	Required	Default	Description
max_operations	integer	no	10000	Rhai operations budget per script invocation. Must be ≥ 1 when set (0 fails validation)
max_call_depth	integer	no	32	Maximum call-stack depth for Rhai functions. Must be ≥ 1 when set
hook_timeout_ms	integer	no	50	Wall-clock limit in milliseconds for one script run. 0 in YAML means use default 50 — not unlimited

rhai:
  max_operations: 10000
  max_call_depth: 32
  hook_timeout_ms: 50

Limits apply to Rule Rhai only. They take effect on the next successful reload or apply — no process restart required. See Sandbox limits — Reload and validation.

Validation

Rule	Error if violated
max_operations ≥ 1 when present	rhai.max_operations must be >= 1 when set
max_call_depth ≥ 1 when present	rhai.max_call_depth must be >= 1 when set

YAML field checks run on conduitctl validate, startup, and reload. Script syntax, missing files, unknown lookup literals, and metric registration are checked later at snapshot compile — see Sandbox limits.

Related topics

• Sandbox limits — behavior, fail-open, observability
• Rules — type: rhai actions
• Data sources — tables for lookup(table, key)
• Config file