Claim 3 — Claude Code dossier

CLAIM 3 / Claude Code

"Exit 2 = Blocking error" — the hooks reference table states exit code 2 on PreToolUse "blocks the tool call" and on Stop "prevents Claude from stopping", while any other exit code is a non-blocking error

partial

Observed

Source-reviewed: exit 2 reliably blocks PreToolUse on Bash, but did not block Agent/Task tool calls — 100% failure across 19 attempted Task blocks over 7 days (#26923); a fix is asserted in a later release and TD has not re-verified it. PostToolUse exit 1 halts Claude awaiting user input despite being documented as non-blocking (#4809), and on Windows v2.1.37–v2.1.63 PreToolUse exit codes were ignored entirely (#21988). The reliable blocking mechanism for Agent and Bash calls is permissionDecision: deny in stdout JSON with exit 0.

Evidence

[1][2]