ephemeral-system-prompt

name	ephemeral-system-prompt
description	Inject non-persisting system prompts via environment variables.
version	0.1.0
author	Hermes
metadata	{"hermes":{"tags":["Configuration","Runtime","SystemPrompt"]}}

Ephemeral System Prompt

Use the HERMES_EPHEMERAL_SYSTEM_PROMPT environment variable to inject instructions into the agent's system prompt that are not persisted to conversation history. This is used for transient constraints, temporary personas, or runtime-specific overrides that should not pollute long-term memory or session logs.

When to Use

• "Set a temporary persona for this specific run"
• "Inject transient operational constraints without modifying history"
• "Apply one-time behavior flags that shouldn't be recalled in future sessions"

Prerequisites

• Access to the shell or environment configuration where the hermes binary is executed.

How to Run

Set the environment variable before invoking the agent through the terminal tool.

Quick Reference

• Variable: HERMES_EPHEMERAL_SYSTEM_PROMPT
• Scope: Process-level (ephemeral)

Procedure

1. Define the transient instructions you wish to inject.
2. Export the variable in your current shell session:

   export HERMES_EPHEMERAL_SYSTEM_PROMPT="You are currently operating in [MODE]. Prioritize X over Y for this session."
   

3. Launch the Hermes agent as usual:

   hermes
   

Pitfalls

• Lack of Persistence: Because these instructions never enter the history, they cannot be retrieved via session_search or memory tools after the process exits.
• Process Bound: The prompt is only active for the lifetime of the process started with that environment variable.

Verification

Verify the behaviorally injected constraint by asking the agent to perform a task that conflicts with its default state but aligns with the ephemeral prompt.