Hmbown/CodeWhale · error · ValueError

max_chars must be > 0

Error message

max_chars must be > 0

What it means

chunk(max_chars=20000, overlap=0) in the embedded Python REPL coerces max_chars with int() and raises ValueError when it is 0 or negative. A positive window is what guarantees the chunk loop advances and keeps chunk counts bounded for large inputs. Note that int('abc') raises a different 'invalid literal' ValueError, so this exact message means the value was numeric but not positive.

Source

Thrown at crates/tui/src/repl/runtime.rs:895

            break
        start, end = m.span()
        snippet_start = max(0, start - 120)
        snippet_end = min(len(_context), end + 120)
        hits.append({
            "index": i,
            "start": start,
            "end": end,
            "match": m.group(0),
            "snippet": _context[snippet_start:snippet_end],
        })
    return hits

def chunk(max_chars=20000, overlap=0):
    """Return full-coverage input chunks with index/start/end/text fields."""
    max_chars = int(max_chars)
    overlap = max(0, int(overlap))
    if max_chars <= 0:
        raise ValueError("max_chars must be > 0")
    if overlap >= max_chars:
        raise ValueError("overlap must be smaller than max_chars")
    chunks = []
    start = 0
    idx = 0
    total = len(_context)
    while start < total:
        end = min(total, start + max_chars)
        chunks.append({"index": idx, "start": start, "end": end, "text": _context[start:end]})
        idx += 1
        if end >= total:
            break
        start = end - overlap
    return chunks

def chunk_context(max_chars=20000, overlap=0):
    """Compatibility alias for chunk()."""
    return chunk(max_chars=max_chars, overlap=overlap)

View on GitHub (pinned to 8880682c63)

Solutions

1. Pass a positive window such as the 20000 default
2. Clamp computed values: max_chars = max(1, int(computed))
3. Skip chunking entirely for empty inputs; chunk returns [] anyway

Example fix

# before
size = len(text) // 1_000_000
chunks = chunk(max_chars=size)
# after
chunks = chunk(max_chars=20000)

window = int(computed_size)
if window <= 0:
    window = 20000  # fall back to the documented default
chunks = chunk(max_chars=window)

try:
    chunks = chunk(max_chars=size)
except ValueError:
    chunks = chunk()  # defaults: max_chars=20000, overlap=0

When it happens

Trigger: Calling chunk(0), chunk(-1), chunk('0'), or passing a computed size that collapses to zero, e.g. max_chars = total // 10**9 or a ratio that rounds down to 0.

Common situations: Generated code deriving the window from a fraction of context length that underflows; passing 0 expecting 'use the default' semantics from other APIs; unit confusion between bytes, tokens, and chars.

Related errors

• overlap must be smaller than max_chars
• unit must be 'chars' or 'lines'
• version must be a semantic release identifier
• max_turns must be between 1 and 10000
• disabled_tools must use Codewhale catalog identifiers: ${",

AI-assisted analysis of Hmbown/CodeWhale@8880682c63 (2026-08-16). Data as JSON: /api/errors/10bf35e2a9ae80dd. Report an issue: GitHub.