support disabling explanataions

docs/src/content/docs/reference/scripts/classify.md

@@ -52,14 +52,27 @@ Each label id should be a single word that encodes into a single token. This all
 A `other` label can be automatically added to the list
 of label to give an escape route for the LLM when it is not able to classify the text.
 
-```js
+```js "other: true"
 const res = await classify(
     "...",
     { ... },
     { other: true }
 )
 ```
 
+## Explanations
+
+By default, the classification prompt is tuned to return a token (`maxToken: 1`) as the label.
+You can enable emitting a justification before returning the label.
+
+```js "explanation: true"
+const res = await classify(
+    "...",
+    { ... },
+    { explanation: true }
+)
+```
+
 ## Model and other options
 
 The `classify` function uses the `classify` [model alias](/genaiscript/reference/scripts/model-aliases) by default.

packages/cli/src/runtime.ts

@@ -16,6 +16,13 @@ export type ClassifyOptions = {
      * Inject a 'other' label
      */
     other?: boolean
+    /**
+     * Explain answers before returning token
+     */
+    explanations?: boolean
+    /**
+     * Options runPrompt context
+     */
     ctx?: ChatGenerationContext
 } & Omit<PromptGeneratorOptions, "choices">
 
@@ -40,7 +47,7 @@ export async function classify<L extends Record<string, string>>(
     answer: string
     logprobs?: Record<keyof typeof labels | "other", Logprob>
 }> {
-    const { other, ...rest } = options || {}
+    const { other, explanations, ...rest } = options || {}
 
     const entries = Object.entries({
         ...labels,
@@ -71,8 +78,8 @@ You must classify the data as one of the following labels.
 ${entries.map(([id, descr]) => `- Label '${id}': ${descr}`).join("\n")}
 
 ## Output
-Provide a single sentence justification for your choice.
-and output the label as a single word on the last line. Do not emit "Label".
+${explanations ? "Provide a single short sentence justification for your choice." : ""}
+Output the label as a single word on the last line (do not emit "Label").
 
 `
             _.fence(
@@ -83,7 +90,7 @@ DATA:
 Why did the chicken cross the road? Because moo.
 
 Output:
-It's a classic joke but the ending does not relate to the start of the joke.
+${explanations ? "It's a classic joke but the ending does not relate to the start of the joke." : ""}
 no
 
 `,
@@ -98,6 +105,7 @@ no
             label: `classify ${choices.join(", ")}`,
             logprobs: true,
             topLogprobs: Math.min(3, choices.length),
+            maxTokens: explanations ? 100 : 1,
             system: [
                 "system.output_plaintext",
                 "system.safety_jailbreak",

packages/sample/genaisrc/classify.genai.mjs

@@ -17,7 +17,8 @@ const joke = await classify(
     {
         yes: "funny",
         no: "not funny",
-    }
+    },
+    { explanations: true }
 )
 
 console.log(joke)