TooManyChildren
Error v195 → v202, v205 → v212, v216 → v216, v217 → v219, v233 → v315, v320 → v326, v334 → v377, v385 → v393, v401 → current 7.63You've exceeded the maximum number of child hotkeys (5).
Why This Error Exists
The child key limit (currently 5) prevents overly complex authority hierarchies that would be expensive to compute and validate. Five children is sufficient for most multi-validator setups while keeping the consensus weight calculations manageable. This limit may change via governance.
Deep Dive
The maximum of 5 children applies per (parent_hotkey, netuid) combination. You can have 5 children on subnet 1 and 5 different children on subnet 2. The limit is enforced at the set_children call - if your array exceeds 5 entries, the transaction fails entirely (no partial success).
Debugging Example
You call set_children(netuid=1, hotkey=5Parent..., children=[C1, C2, C3, C4, C5, C6]). Error: TooManyChildren. You have 6 children but max is 5. Solution: Remove one child from the array. Consider which child provides least value and exclude it.
Prevention Tips
- Validate children.length <= 5 before calling set_children
- If you need more children, consider a tree structure: parent -> 5 children, each child -> 5 grandchildren
- Use clear naming/documentation to track which children are active
From Chain Metadata
Too many children MAX 5.
What This Means
You've exceeded the maximum number of child hotkeys (5).
Common Causes
- Trying to add more than 5 children
- Maximum is a network-wide limit
How to Fix
- Reduce the number of children to 5 or fewer
- Remove some existing children before adding new ones
Storage to Check
Thrown By
Version History
Runtime Info
- Pallet Index
- 7
- Error Index
- 63
- Error Code
- 7.63
- Runtime Version
- v411