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Rule priority, scope & exceptions
Use this to align rules with the senior-level structure (P0/P1/P2, scope, exceptions/tradeoffs).
backend ruleP1universalStack: any
httpvalidationerror-handlingapi-design
Return 400 for missing required request parameters
When a required query/body param is absent, respond with 400 Bad Request rather than returning empty data or proceeding.
PR: hegnar-ws · org-mining-hist-2026-06Created: Jun 18, 2026
Bad example
Old codetypescript
| 1 | const { ids } = req.query; |
| 2 | if (!ids) return res.json([]); |
Explanation (EN)
Objašnjenje (HR)
Good example
New codetypescript
| 1 | const { ids } = req.query; |
| 2 | if (!ids) return res.status(400).json({ error: 'ids is required' }); |
Explanation (EN)
Objašnjenje (HR)