CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOT

Updated October 14, 2026 by Alex Sorokoletov

CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOT is a Claude Code environment variable. Added in v2.1.290 and still present in v2.1.295. It is not in the official reference.

Status	Present in v2.1.295
Added	Added in v2.1.290
Category	Agents and subagents
Official docs	Not listed

How to set it

For one session, export it in the shell that starts Claude Code:

export CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOT=<value>
claude

To apply it to every session, add it to the env object of a settings file:

// ~/.claude/settings.json
{
  "env": {
    "CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOT": "<value>"
  }
}

Related variables

CLAUDE_CODE_ENABLE_APPEND_SUBAGENT_PROMPT: Authorizes SDK callers to append a custom string to a subagent's system prompt via options.appendSubagentSystemPrompt.
CLAUDE_CODE_SUBAGENT_PROMPT_CACHE_TTL
CLAUDE_CODE_FORK_SUBAGENT: Changelog-confirmed[1]: set to 1 to run subagents as forked processes (v2.1.117 on external builds, v2.1.121 extended to non-interactive SDK/-p sessions).
CLAUDE_CODE_FORWARD_SUBAGENT_TEXT: Includes subagent text and thinking in stream-json output, paired with a new --forward-subagent-text flag.
CLAUDE_CODE_MAX_SUBAGENT_SPAWN_DEPTH: Nesting-depth cap on delegation, default 1 — subagents no longer spawn their own subagents, and the team roster stays flat.
CLAUDE_CODE_SUBAGENT_MODEL: Force a specific model for sub-agent operations.
CLAUDE_CODE_SUBAGENT_MODEL_FORCE
CLAUDE_CODE_SUBAGENT_MODELU: The trailing-U variant flagged as a likely typo in v2.1.84 has been removed.

Frequently asked questions

Which Claude Code version has CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOT?

Added in v2.1.290 and still present in v2.1.295.

How do I set CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOT?

Export it before starting Claude Code (export CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOT=value), or add it to the "env" object in ~/.claude/settings.json to apply it to every session.

All variables, searchable: Claude Code environment variables.