Interfaces

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Lane is built around a set of pluggable interfaces. Implementing one lets you swap out a component (e.g., a different LLM provider, a new TTS service, a custom memory backend) without touching the rest of the codebase.

ILLM — Language Model

File: Wizard/LLM/ILLM.cs

The interface for the language model backend.

public interface ILLM
{
    Task<MessageContainer> Prompt(
        List<MessageContainer> context,
        string                 systemPrompt,
        string                 cachedDynamicPrompt = "",
        string                 dynamicPrompt       = ""
    );
}

Parameters

Parameter Description
context The conversation messages to send as the human turn
systemPrompt The static system prompt (e.g. contents of Respond.md)
cachedDynamicPrompt A dynamic system prompt suffix that is relatively stable across calls (e.g. memory context). Passed as a cache-eligible prefix where supported.
dynamicPrompt A dynamic system prompt suffix that changes every call (e.g. recent conversation, current timestamp)

Returns

A MessageContainer containing the LLM's response text.

Current Implementations

Class Provider Model Config key
Claude Anthropic Claude Haiku 4.5 "LLM": "Claude"
DeepSeek DeepSeek deepseek-chat "LLM": "DeepSeek"

Claude assembles the three prompt segments into a single system prompt, with cachedDynamicPrompt marked for prompt caching. DeepSeek uses the OpenAI-compatible API at https://api.deepseek.com/v1 and supports stop sequences.

The active LLM is selected via the "LLM" field in appsettings.json (see configuration.md).

IMemoryHandler — Memory Backend

File: Wizard/Memory/IMemoryHandler.cs

The interface for a memory storage and retrieval backend.

public interface IMemoryHandler
{
    Task RememberMessage(MessageContainer message);
    Task<List<MessageContainer>> RecallMemory(MessageContainer? message);
    bool IsRecent();
    JToken Serialize();
    void   Deserialize(JToken data);
}

Methods

Method Description
RememberMessage(message) Store a message in this handler's backing store
RecallMemory(message?) Retrieve relevant messages; message is the query (may be null for monologue calls)
IsRecent() Return true if this handler tracks the current/recent conversation; false if it retrieves older long-term context. Controls which prompt template the recalled messages are injected into.
Serialize() Serialize handler state to JSON for persistence
Deserialize(data) Restore handler state from a previously serialized JSON token

Current Implementations

Class IsRecent() Description
SlidingWindow true Keeps a fixed-size window of the most recent messages. Can be configured to track either regular messages or thoughts (ForThoughts).
Summary false Maintains a running LLM-generated summary of the full conversation history, updated every N messages.
RAG false Stores all messages as vector embeddings in Qdrant and retrieves the most semantically similar ones to the current message.

IMouth — Text-to-Speech

File: Wizard/Head/Mouths/IMouth.cs

The interface for a TTS provider.

public interface IMouth
{
    Task<byte[]> Speak(string text);
}

Parameters

Parameter Description
text The text to synthesize

Returns

Raw PCM audio bytes, which the Discord body Opus-encodes and streams to the voice channel.

Current Implementations

Class Provider Relevant config keys
ElevenlabsTTS ElevenLabs ELEVENLABS_KEY, Speech.Voice, Speech.Stability, Speech.Similarity, Speech.Tune
AzureTTS Azure Cognitive Services AZURE_KEY, AZURE_REGION, Speech.Voice, Speech.Tempo, Speech.Pitch, Speech.Rate, Speech.Tune

IEar — Speech-to-Text

File: Wizard/Head/Ears/IEar.cs

The interface for an STT provider.

public interface IEar
{
    Task<string> Listen();
}

Returns

A transcribed string from the audio stream. Returns an empty or whitespace string if nothing intelligible was heard; the caller skips these.

Each IEar instance is bound to a single user's audio stream (DiscordAudioStream) and runs in a per-user loop for the duration of their time in the voice channel.

Current Implementations

Class Provider Relevant config keys
AzureSTT Azure Cognitive Services AZURE_KEY, AZURE_REGION

MessageContainer

File: Wizard/LLM/MessageContainer.cs

Not an interface, but the core data type passed between all components. Wraps a message with its author, type, and timestamp.

Author

Value Meaning
Author.User A message from a human
Author.Bot A message or thought from Lane

MessageType

Value Meaning
MessageType.Text A regular text message
MessageType.Image An image (stored as a URL; sent to the LLM as an image content block)
MessageType.Thought An internal monologue thought; wrapped in <thought> tags when sent to the LLM, and prefixed with "Lane thinks:" in context strings
How it works Theory