claude-subagents skill: a failed command is reported verbatim, never filled in

claude-plugins/plugins/base/skills/claude-subagents/SKILL.md

@@ -176,6 +176,22 @@ On completion: read the report file, spot-check a handful of results
 yourself (don't trust the self-report blind), then summarize. Surface
 anything the sub-agent left ambiguous or exempted for a human call.
 
+## A failed command is the result, not a gap to fill
+
+Tell every subagent, in the prompt: if a command FAILS (non-zero exit, an
+error like "no repo specified", empty output where output was expected),
+STOP and report the failed command and its output verbatim as the result.
+No workaround, no inference, no plausible fill-in. An invented answer is
+worse than none, because you will act on it.
+
+This happens: a subagent spawned in a scratch directory with no git
+`origin` remote could not run its forge CLI, mentioned that in one line,
+then filled the report with invented issue numbers and a confident
+conclusion that was the opposite of the truth. The report looked cleaner
+than a real one. So spawn tool-using subagents where their tools work (a
+real checkout, or pass the target explicitly), and spot-check one cheap
+fact from every report against the real system.
+
 ## Pitfalls (all observed in practice)
 
 - Using a model bigger than yourself → paying premium cost for