Refactor

lib/sampling.ts

@@ -0,0 +1,71 @@
+import type { LLamaChatPromptOptions } from "node-llama-cpp";
+
+export const samplingProfiles = ["creative", "model-default"] as const;
+export type SamplingProfile = (typeof samplingProfiles)[number];
+export type GenerationKind = "post" | "reply";
+
+type SamplingOptions = Pick<
+  LLamaChatPromptOptions,
+  "temperature" | "minP" | "topK" | "topP" | "repeatPenalty"
+>;
+
+export const isSamplingProfile = (value: string): value is SamplingProfile =>
+  samplingProfiles.some((profile) => profile === value);
+
+const creativeOptions = (kind: GenerationKind): SamplingOptions => ({
+  temperature: kind === "post" ? 1.25 : 0.8,
+  minP: kind === "post" ? 0.05 : 0.1,
+  repeatPenalty: { lastTokens: 128, penalty: 1.15 },
+});
+
+/**
+ * Sampling values published on each model card. These are useful as a fair
+ * baseline, but are not necessarily the most interesting settings for this bot.
+ */
+export function getSamplingOptions(
+  modelName: string,
+  profile: SamplingProfile,
+  kind: GenerationKind,
+): SamplingOptions {
+  if (profile === "creative") return creativeOptions(kind);
+
+  const normalized = modelName.toLowerCase();
+  if (normalized.includes("lfm2.5")) {
+    return {
+      temperature: 0.1,
+      topK: 50,
+      repeatPenalty: { lastTokens: 128, penalty: 1.1 },
+    };
+  }
+  if (normalized.includes("lfm2-")) {
+    return {
+      temperature: 0.3,
+      minP: 0.15,
+      repeatPenalty: { lastTokens: 128, penalty: 1.05 },
+    };
+  }
+  if (normalized.includes("qwen3.5")) {
+    return {
+      temperature: 1,
+      topK: 20,
+      topP: 0.95,
+      // The model card's 1.5 presence penalty is outside node-llama-cpp's
+      // documented 0..1 range, so use the largest supported value.
+      repeatPenalty: {
+        lastTokens: 128,
+        penalty: 1,
+        presencePenalty: 1,
+      },
+    };
+  }
+  if (normalized.includes("gemma-3") || normalized.includes("gemma-4")) {
+    return {
+      temperature: 1,
+      topK: 64,
+      topP: 0.95,
+      repeatPenalty: { lastTokens: 128, penalty: 1.1 },
+    };
+  }
+
+  return creativeOptions(kind);
+}