[Bug]: explainer check receipt is truncated at ~8 KiB on macOS when stdout is a pipe, so deliver/finalize fail with "Could not parse the successful artifact-check receipt" #1130

Archify version or commit

3.2.0 (installed skill package); reproduced against main at 81c6be8.

Installation method

Claude Code skill (~/.claude/skills/archify)

Diagram type

explainer

Exact command

node bin/archify.mjs finalize explainer candidate.archify.md pricing-backdata.html --json
# and directly:
node bin/archify.mjs check pricing-backdata.html --json | wc -c

Minimal redacted JSON reproduction

Any explainer whose artifact-check receipt is larger than one pipe chunk. Mine has 7 panels and 4 native diagrams (1 architecture with 11 edges, 1 workflow, 2 erd); its full receipt is 21,289 bytes because the diagram-check section lists minimumProjectedTextPx per node and edge. A smaller explainer (receipt under 8 KiB) does not reproduce.

Validation receipt or exact error

{"code":"delivery/receipt-invalid","severity":"error",
 "message":"Could not parse the successful artifact-check receipt: Unterminated fractional number in JSON at position 8127 (line 270 column 43)"}

finalize reports gates.validate = not-run, deliver = fail. Running the checker alone with a piped stdout gives exactly 8192 bytes:

$ node archify/bin/archify.mjs check pricing-backdata.html --json | wc -c
    8192

and the output ends mid-number: "minimumProjectedTextPx": 6.75109717868.

Expected behavior

The checker prints its whole receipt and deliver/finalize pass (the artifact itself is fine: validate passes and the same HTML opens correctly).

Actual behavior

archify/scripts/check-render-output.mjs takes the explainer branch (isExplainerHtml), prints the receipt with console.log and calls process.exit() on the next line. On macOS process.stdout is asynchronous when it is a pipe, so the process exits after the first chunk and the receipt is cut. deliver spawns the checker with stdio: 'pipe', fails to JSON.parse the partial output and reports delivery/receipt-invalid. The non-explainer path at the bottom of the same script already avoids this by setting process.exitCode and letting stdout drain (the comment there says so); only the explainer branch still exits eagerly.

This is distinct from #525 / #590 (parent-side maxBuffer): here the child truncates its own output.

Environment

macOS 26.3 (Darwin 25.3.0) · Node 22 · zsh. Not reproduced on Linux, where pipe writes are synchronous.

Final checks

• I searched existing issues for the same problem.
• I removed access tokens, credentials, private repository contents, and personal or customer data.

I have a one-file fix ready (exit from the process.stdout.write callback and hold the module so the diagram path does not print a second receipt); I will open it as a draft PR referencing this issue.