LLM-Only Plugin Example

This example demonstrates a plugin that only implements the LLMPlugin interface.

Features

PreLLMHook: Intercepts requests before they reach the LLM provider
- Logs request details
- Modifies requests (adds system message)
- Stores metadata in context
PostLLMHook: Intercepts responses after the LLM provider responds
- Logs response details
- Accesses context metadata
- Handles errors

Use Cases

Request/response logging
Adding default system messages
Request validation
Response filtering
Token counting
Cost tracking

Building

make build

This creates build/llm-only.so

Configuration

Add to your Bifrost config:

{
  "plugins": [
    {
      "path": "/path/to/llm-only.so",
      "name": "llm-only",
      "display_name": "LLM Request Logger",
      "enabled": true,
      "type": "llm",
      "config": {
        "inject_system_message": true,
        "system_message_text": "You are a helpful assistant.",
        "enable_logging": true,
        "log_requests": true,
        "log_responses": true
      }
    }
  ]
}

Note:

name is the system identifier (from GetName()) and is not editable
display_name is shown in the UI and is editable by users

Configuration Options

Option	Type	Default	Description
`inject_system_message`	boolean	`true`	Enable/disable automatic system message injection
`system_message_text`	string	`"You are a helpful assistant..."`	Custom system message to inject
`enable_logging`	boolean	`true`	Enable/disable detailed logging
`log_requests`	boolean	`true`	Log request details (provider, model)
`log_responses`	boolean	`true`	Log response details (ID, choices)

Example Configurations

Minimal logging:

{
  "config": {
    "enable_logging": false,
    "log_requests": false,
    "log_responses": false
  }
}

Custom system message:

{
  "config": {
    "inject_system_message": true,
    "system_message_text": "You are a technical expert. Provide detailed, accurate answers."
  }
}

No system message injection:

{
  "config": {
    "inject_system_message": false
  }
}