Chunked File Writer

Chunked File Writer

This environment routes API traffic through a gateway that drops long streaming responses. Any single tool call whose generated content exceeds roughly 100 lines is likely to stall the session. Therefore, NEVER write a large file in one Write call. Follow this procedure for every file longer than ~80 lines.

Procedure

1. Plan the sections first. Before writing anything, list the file's sections (e.g., header/docstring, constants, function 1, function 2, ..., main, entry point). Aim for sections of 40–80 lines each. State the section list in one short sentence, then begin.

2. Write the skeleton. Create the file with a single small Write containing ONLY:

   • the header comment/docstring,
   • imports and constants,
   • a one-line placeholder comment for each planned section, in order, e.g.: # SECTION 2: reactor_period_regression — implemented in a later edit The skeleton must be under 60 lines.

3. Fill sections one at a time with Edit. For each section, make ONE Edit call that replaces that section's placeholder comment with the full implementation. Hard limits per Edit:

   • max ~80 lines / ~3000 characters of new content;
   • if a section is bigger than that, split it into part A / part B with its own placeholder for part B. Never combine two sections into one Edit. Never rewrite the whole file.

4. No batching, no parallel writes. One section per tool call, each in its own turn of tool use. Keep any prose between tool calls to a single short sentence.

5. Verify at the end. After the last section:

   • run a syntax check (e.g., python -m py_compile <file> for Python);
   • grep the file for remaining SECTION placeholders to confirm none are left: grep -n "SECTION" <file> should return nothing (or only intentional matches);
   • report the final line count.

Also applies to

• Rewrites and refactors: modify existing large files with several small targeted Edits, never one whole-file replacement.
• Long markdown/reports/configs: same skeleton-then-sections procedure.
• Small files (< 80 lines): write normally in a single call; this procedure is unnecessary overhead there.

If a stall happens anyway

If a tool call appears to hang or a turn is interrupted, resume by checking which placeholders remain in the file and continue from the first unfilled section. Never restart the file from scratch.