$ rg -n -i "atomic|prefix-preserv" <Pi extensions docs> <Claude hook docs>
NO MATCH: neither installed runtime document states an atomic/prefix-preserving transport guarantee.

$ rg -n -C 3 "#### context|event.messages - deep copy|return \{ messages" <Pi extensions docs>
638-});
639-```
640-
641:#### context
642-
643-Fired before each LLM call. Modify messages non-destructively. See [Session Format](session-format.md) for message types.
644-
645-```typescript
646-pi.on("context", async (event, ctx) => {
647:  // event.messages - deep copy, safe to modify
648-  const filtered = event.messages.filter(m => !shouldPrune(m));
649:  return { messages: filtered };
650-});
651-```
652-

$ rg -n -C 3 "additionalContext|add to the default system prompt" <Claude installed docs>
/home/hermes/.config/mosaic/runtime/claude/RUNTIME.md-58-  tiered models via the Task `model` param).
/home/hermes/.config/mosaic/runtime/claude/RUNTIME.md-59-
/home/hermes/.config/mosaic/runtime/claude/RUNTIME.md-60-Note: PostToolUse hook plain stdout on exit 0 goes to the debug log, not model context — only
/home/hermes/.config/mosaic/runtime/claude/RUNTIME.md:61:`hookSpecificOutput.additionalContext` (or exit-2 stderr) enters context.
--
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/README.md-59-expressed as
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/README.md-60-[subagents](https://docs.claude.com/en/docs/claude-code/sub-agents), not as
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/README.md-61-SessionStart hooks. Subagents change the system prompt while SessionStart hooks
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/README.md:62:add to the default system prompt.
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/README.md-63-
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/README.md-64-## Managing changes
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/README.md-65-
--
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-1-#!/usr/bin/env bash
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-2-
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh:3:# Output the explanatory mode instructions as additionalContext
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-4-# This mimics the deprecated Explanatory output style
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-5-
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-6-cat << 'EOF'
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-7-{
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-8-  "hookSpecificOutput": {
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-9-    "hookEventName": "SessionStart",
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh:10:    "additionalContext": "You are in 'explanatory' output style mode, where you should provide educational insights about the codebase as you help with the user's task.\n\nYou should be clear and educational, providing helpful explanations while remaining focused on the task. Balance educational content with task completion. When providing insights, you may exceed typical length constraints, but remain focused and relevant.\n\n## Insights\nIn order to encourage learning, before and after writing code, always provide brief educational explanations about implementation choices using (with backticks):\n\"`★ Insight ─────────────────────────────────────`\n[2-3 key educational points]\n`─────────────────────────────────────────────────`\"\n\nThese insights should be included in the conversation, not in the codebase. You should generally focus on interesting insights that are specific to the codebase or the code you just wrote, rather than general programming concepts. Do not wait until the end to provide insights. Provide them as you write code."
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-11-  }
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-12-}
/home/hermes/.claude/plugins/marketplaces/claude-plugins-official/plugins/explanatory-output-style/hooks-handlers/session-start.sh-13-EOF
