Claude Haiku 5.5 (effort default (no --effort flag) · thinking on) on Implement a reader/writer for a documented chunked binary container (LEB128 lengths, CRC-32, zlib chunks, critical vs ancillary)

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  "result": "I implemented `read(buf)` and `write(...)` in `chnk.py`. `FormatError(msg, offset)` is unchanged. The round-trip and error-case tests I ran all pass, and the test script lives in `/tmp/chnk_tests/`, outside the work directory. This isn't a git repo, so I didn't commit anything.\n\nWhere FORMAT.md left room, I chose the stricter reading:\n\n- **META:** an empty META payload, a trailing `\\n`, or an empty line is rejected as a bad META line. A key containing no `=` or an empty key is rejected too.\n- **DATZ:** the stream must be complete, with no trailing bytes after it. A truncated or padded zlib stream is \"bad zlib data\" at the chunk's offset.\n- **Writer:** it raises `ValueError` for inputs it can't represent: an empty key, a key containing `=` or a newline, a value containing a newline, `chunk_size < 1`, or a chunk longer than the 5-byte varint limit. FORMAT.md doesn't cover these, so they are my addition.\n- **Missing END:** when the input ends exactly at a chunk boundary, the error is at `len(input)`. A chunk cut off partway is reported at that chunk's start.\n\nIf you want the looser reading for any of these, say so and I'll change it.",
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