Function buildLesson

src/skills/learning/failures.ts:91–103

(p: FailurePattern)

/** Templated, DETERMINISTIC caution for a recurring failure. Never LLM-phrased. */
export function buildLesson(p: FailurePattern): string {
  const sig = p.signature.toLowerCase();
  const verb = (advice: string) => `When using \`${p.tool}\`: ${advice} (this failed ${p.count}× across ${p.distinctTasks} tasks).`;
  if (/(not found|does not exist|cannot find|no such|unknown symbol|undefined)/.test(sig)) {
    if (p.tool.startsWith('edit_symbol')) return verb('confirm the symbol exists first (grep / code-graph) — it has repeatedly not been found.');
    return verb('verify the target exists before calling it — the target has repeatedly not been found.');
  }
  if (/(permission|denied|eacces|not permitted)/.test(sig)) return verb('check permissions / path writability before retrying.');
  if (/(timeout|timed out|etimedout)/.test(sig)) return verb('it has repeatedly timed out — narrow the scope or raise the timeout.');
  if (/(syntax|parse|unexpected token)/.test(sig)) return verb('the produced input repeatedly failed to parse — double-check syntax before submitting.');
  if (/(already exists|eexist)/.test(sig)) return verb('the target already exists — read/update it instead of creating.');
  return verb(`it has failed repeatedly with: "${p.sample.slice(0, 80)}". Check its preconditions before using it again.`);
}

/** Build the system-prompt block from confirmed patterns (top-K). Empty when none. */
export function buildLessonsBlock(patterns: FailurePattern[], topK = 5): string {