What causes "Summary exceeds ${config.summaryHardLimit} bytes" in can1357/oh-my-pi?

Truncate or rewrite the summary before calling post-processing (e.g. cut at word boundary under the limit)

can1357/oh-my-pi · error · Error

Summary exceeds ${config.summaryHardLimit} bytes

Error message

Summary exceeds ${config.summaryHardLimit} bytes

What it means

postProcessCommitMessage enforces a hard byte limit on the commit summary (first line) after lowercasing, verb normalization, and punctuation trimming. If the summary still exceeds config.summaryHardLimit bytes, it throws instead of emitting an over-long commit subject (raised in postProcessCommitMessage, called by generateConventionalCommit, generateFastCommit, messageFromAnalysis, validateAndProcess).

Source

Thrown at packages/coding-agent/src/commit/conventional/normalization.ts:217

	return joinFirstRest(`${past}${suffix}`, rest);
}

/** Normalize summary, body, and footers before final validation. */
export function postProcessCommitMessage(
	message: ConventionalCommit,
	config: ConventionalGenerationConfig,
): ConventionalCommit {
	let summary = normalizeCommitUnicode(message.summary);
	summary = summary.replaceAll("\r", " ").replaceAll("\n", " ").split(/\s+/).filter(Boolean).join(" ");
	summary = summary
		.trim()
		.replace(/[.;:]+$/g, "")
		.trim();
	summary = lowercaseFirstToken(summary);
	summary = normalizeSummaryVerb(summary, message.type);
	summary = lowercaseFirstToken(summary.trim()).replace(/\.+$/g, "").trim();
	if (Buffer.byteLength(summary) > config.summaryHardLimit) {
		throw new Error(`Summary exceeds ${config.summaryHardLimit} bytes`);
	}

	const body: string[] = [];
	for (const raw of message.body) {
		let detail = normalizeCommitUnicode(raw).replaceAll("\r", " ").replaceAll("\n", " ");
		detail = detail
			.trim()
			.replace(/^[•\-*+]+/, "")
			.trim()
			.split(/\s+/)
			.filter(Boolean)
			.join(" ");
		detail = detail.replace(/[.;,]+$/g, "").trim();
		if (!detail) continue;
		const first = firstCodePoint(detail);
		if (first && first === first.toLowerCase() && first !== first.toUpperCase()) {
			detail = first.toUpperCase() + detail.slice(first.length);
		}

View on GitHub (pinned to 9690622007)

Solutions

Truncate or rewrite the summary before calling post-processing (e.g. cut at word boundary under the limit)
Regenerate with prompt instruction to keep the subject short
Raise config.summaryHardLimit if your project allows longer subjects
Beware multibyte text: measure with Buffer.byteLength and trim to the byte budget

Example fix

// before
const message = await postProcessCommitMessage(raw, config);
// after: pre-trim the summary
const limit = config.summaryHardLimit;
let summary = raw.summary;
while (Buffer.byteLength(summary) > limit) summary = summary.slice(0, summary.lastIndexOf(" ")).trim();
const message = await postProcessCommitMessage({ ...raw, summary }, config);

Defensive patterns

Strategy: validation

Validate before calling

if (Buffer.byteLength(summary) > config.summaryHardLimit) {
  summary = summary.slice(0, config.summaryHardLimit).trim();
}

Try / catch

try {
  message = postProcessCommitMessage(raw, config);
} catch (err) {
  if (err instanceof Error && err.message.includes("Summary exceeds")) {
    // regenerate with a brevity instruction or truncate the subject
  }
  throw err;
}

Prevention

Instruct the model to keep subjects under ~72 characters
Account for UTF-8 multibyte expansion when measuring length
Pre-truncate long subjects at word boundaries before post-processing

When it happens

Trigger: Calling any commit-message generation/validation entry point with a message whose normalized summary exceeds summaryHardLimit bytes — typically very long model-generated subjects, CJK/multibyte text (byte-length counts UTF-8 bytes, not characters), or a config with an unusually small hard limit.

Common situations: Models ignoring subject-length instructions, multibyte characters pushing byte counts over the limit while looking short, overly verbose generated summaries after scope prefixing, or tightened summaryHardLimit config.

Related errors

AI-assisted analysis of can1357/oh-my-pi@9690622007 (2026-08-31). Data as JSON: /api/errors/7c4aab8f2c5c6a6d. Report an issue: GitHub.