Do you need leave to amend?
Five questions on CCP 472(a), ending in the answer and the authority for it. Handles the supplemental-complaint trap and the unresolved co-defendant split.
Open the tool →2 interactive tools
Tools
Each one runs entirely in your browser. Nothing you enter is saved, sent, or tracked.
Local rules on amending, by county
All 58 California counties, with each entry marked verified or not. Most have no rule at all, which is itself worth knowing.
Open the tool →A tool gives you an answer. It does not give you the reasoning, the case law, or the ways the answer goes wrong. Those are in the guides, and each tool links to the one behind it.