CLAUDE_CODE_SKIP_PROMPT_HISTORY disables all transcript persistence since 2.1.77 #36091

Bug Description

CLAUDE_CODE_SKIP_PROMPT_HISTORY=1 silently disables all session transcript persistence starting in version 2.1.77.

Quick Summary

Previously (2.1.76 and earlier), this env var only controlled prompt history (up-arrow recall in history.jsonl).

The regression: Zero .jsonl transcript files are written for any session, breaking:

• /resume
• /stats
• Session sharing
• All features that depend on transcript data

What Changed

The Gatekeeper Method

The shouldSkipPersistence() method on the session storage class gates every call to appendEntry() and materializeSessionFile() — the two functions responsible for creating and writing to transcript .jsonl files.

The Addition

A 4th condition was added in 2.1.77 that checks CLAUDE_CODE_SKIP_PROMPT_HISTORY.

shouldSkipPersistence() {
  let H = isEnvVarTrue(process.env.TEST_ENABLE_SESSION_PERSISTENCE);
  return getNodeEnv() === "test" && !H
    || getSettings()?.cleanupPeriodDays === 0
    || isSkipPersistence();
}

shouldSkipPersistence() {
  let H = isEnvVarTrue(process.env.TEST_ENABLE_SESSION_PERSISTENCE);
  return getNodeEnv() === "test" && !H
    || getSettings()?.cleanupPeriodDays === 0
    || isSkipPersistence()
    || isEnvVarTrue(process.env.CLAUDE_CODE_SKIP_PROMPT_HISTORY);  // <-- NEW
}

The Effect

Result: If CLAUDE_CODE_SKIP_PROMPT_HISTORY is set to any truthy value ("1", "true", "yes"), no transcript files are created or written to.

Both appendEntry() and materializeSessionFile() bail out immediately when shouldSkipPersistence() returns true.

How It Breaks

Original Purpose

The CLAUDE_CODE_SKIP_PROMPT_HISTORY env var was introduced to let users disable prompt history recall (the ↑ up-arrow feature that writes to history.jsonl).

Independent Implementation

That behavior is handled by a completely separate function which checks the same env var independently:

function writePromptHistoryEntry(H) {
  if (isEnvVarTrue(process.env.CLAUDE_CODE_SKIP_PROMPT_HISTORY)) return;
  // ... writes to history.jsonl
}

What Users Expected vs. What Happened

Users who set this env var expected it to only disable prompt history, as the name implies.

Instead, starting in 2.1.77, it also disables:

Impact

Silent Data Loss

No error, warning, or log message is emitted. Sessions appear to work normally but produce no persistent record.

Retroactive

Every session since upgrading to 2.1.77 has zero transcript data. There is no way to recover these transcripts.

Mislabeled Env Var

The env var name says skip prompt history but now controls all persistence. Users have no reason to expect this side effect.

Steps to Reproduce

1. Configure the env var

Set CLAUDE_CODE_SKIP_PROMPT_HISTORY to "1" in ~/.claude/settings.json:

{
  "env": {
    "CLAUDE_CODE_SKIP_PROMPT_HISTORY": "1"
  }
}

2. Start a session

Start a new Claude Code session (claude in terminal)

3. Have a conversation

Send any message and have a conversation

4. Exit

Exit the session

5. Check for transcripts

find ~/.claude/projects/ -name "*.jsonl" -newer /tmp/marker -type f

6. Result

No transcript .jsonl is created for the session

Expected Behavior

CLAUDE_CODE_SKIP_PROMPT_HISTORY should only disable prompt history (history.jsonl), not session transcript persistence.

This was the behavior in 2.1.76 and earlier.

Recommended Fix

If Dual-Purpose Behavior Is Intended

If CLAUDE_CODE_SKIP_PROMPT_HISTORY is meant to control both prompt history and session transcripts, the solution is:

1. Rename the env var to something clear: CLAUDE_CODE_SKIP_ALL_PERSISTENCE
2. Update documentation to explicitly state it disables both features
3. Provide a migration notice for users who have the old env var set

This would prevent silent breakage for existing users.

Environment