Yes, this is a known issue. A significant amount of Edit tool calls fails in Pi witg newer models.

https://lucumr.pocoo.org/2026/7/4/better-models-worse-tools/

https://blog.can.ac/2026/02/12/the-harness-problem/

It's worse than I expected.

I don't understand peoples expectation. If our language skills were as non-ambiguous as a coding language, we'd have solved world hunger by now.

So why would we expect all these bizarre bizantine language models to all conform to how a request is both made, expected and massaged.

For awhile, I was getting bizarre opencode tool errors where the only problem was the model was passing in a "1.0" or "0.0" where the harness dutifully wanted an integer. Of course 0.0 is the same as an integer in practical operations.

I have one core complex task where there are a number of simple errors like this. The easiest thing for me was to just have a post-processing script that performs: lint > mark known fail-early results > fix common errors (all formatting or type errors right now) > relint > final pass / fail > pass to next step (retry with tweaks / user in the loop since I don't have the token budget to just blindly keep trying the same thing).

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