"Looks like X" without checking is wrong about half the time. Column names, table names, enum values, endpoints, IDs — never assert them from memory. Read them from the live system first.
This applies hardest to things you're about to change. Before touching any load-bearing value, trace its actual runtime resolution path: find which field the consumer really reads. The field that looks like the target frequently isn't the one in the real code path, and changing the decoy leaves the bug intact while making you believe it's fixed.
There's a sharper version of this failure. If your brief's premise is false — you ask for something that already exists — a capable agent will "fix" the non-bug, inventing a change nobody wanted. Verify the premise before you write the brief, not after.
Run the seed: turn an assumption-laden request into one that reads first.