feat(api): add token logprobs to chat completions

api.md

@@ -37,6 +37,7 @@ Types:
 - <code><a href="./src/resources/chat/completions.ts">ChatCompletionNamedToolChoice</a></code>
 - <code><a href="./src/resources/chat/completions.ts">ChatCompletionRole</a></code>
 - <code><a href="./src/resources/chat/completions.ts">ChatCompletionSystemMessageParam</a></code>
+- <code><a href="./src/resources/chat/completions.ts">ChatCompletionTokenLogprob</a></code>
 - <code><a href="./src/resources/chat/completions.ts">ChatCompletionTool</a></code>
 - <code><a href="./src/resources/chat/completions.ts">ChatCompletionToolChoiceOption</a></code>
 - <code><a href="./src/resources/chat/completions.ts">ChatCompletionToolMessageParam</a></code>

examples/logprobs.ts

@@ -0,0 +1,23 @@
+#!/usr/bin/env -S npm run tsn -T
+
+import OpenAI from 'openai';
+
+// gets API Key from environment variable OPENAI_API_KEY
+const openai = new OpenAI();
+
+async function main() {
+  const stream = await openai.beta.chat.completions
+    .stream({
+      model: 'gpt-4',
+      messages: [{ role: 'user', content: 'Say this is a test' }],
+      stream: true,
+      logprobs: true,
+    })
+    .on('logprob', (logprob) => {
+      console.log(logprob);
+    });
+
+  console.dir(await stream.finalChatCompletion(), { depth: null });
+}
+
+main();

src/index.ts

@@ -242,6 +242,7 @@ export namespace OpenAI {
   export import ChatCompletionNamedToolChoice = API.ChatCompletionNamedToolChoice;
   export import ChatCompletionRole = API.ChatCompletionRole;
   export import ChatCompletionSystemMessageParam = API.ChatCompletionSystemMessageParam;
+  export import ChatCompletionTokenLogprob = API.ChatCompletionTokenLogprob;
   export import ChatCompletionTool = API.ChatCompletionTool;
   export import ChatCompletionToolChoiceOption = API.ChatCompletionToolChoiceOption;
   export import ChatCompletionToolMessageParam = API.ChatCompletionToolMessageParam;

src/lib/ChatCompletionRunFunctions.test.ts

@@ -146,6 +146,7 @@ function* contentChoiceDeltas(
     yield {
       index,
       finish_reason: i === deltas.length - 1 ? 'stop' : null,
+      logprobs: null,
       delta: {
         role,
         content: deltas[i] ? `${deltas[i]}${i === deltas.length - 1 ? '' : ' '}` : null,
@@ -593,6 +594,7 @@ describe('resource completions', () => {
             {
               index: 0,
               finish_reason: 'function_call',
+              logprobs: null,
               message: {
                 role: 'assistant',
                 content: null,
@@ -645,6 +647,7 @@ describe('resource completions', () => {
             {
               index: 0,
               finish_reason: 'stop',
+              logprobs: null,
               message: {
                 role: 'assistant',
                 content: `it's raining`,
@@ -716,6 +719,7 @@ describe('resource completions', () => {
             {
               index: 0,
               finish_reason: 'function_call',
+              logprobs: null,
               message: {
                 role: 'assistant',
                 content: null,
@@ -808,6 +812,7 @@ describe('resource completions', () => {
             {
               index: 0,
               finish_reason: 'function_call',
+              logprobs: null,
               message: {
                 role: 'assistant',
                 content: null,
@@ -867,6 +872,7 @@ describe('resource completions', () => {
             {
               index: 0,
               finish_reason: 'stop',
+              logprobs: null,
               message: {
                 role: 'assistant',
                 content: `there are 3 properties in {"a": 1, "b": 2, "c": 3}`,
@@ -953,6 +959,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'function_call',
+                logprobs: null,
                 message: {
                   role: 'assistant',
                   content: null,
@@ -1006,6 +1013,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'function_call',
+                logprobs: null,
                 message: {
                   role: 'assistant',
                   content: null,
@@ -1078,6 +1086,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'stop',
+                logprobs: null,
                 message: {
                   role: 'assistant',
                   content: `there are 3 properties in {"a": 1, "b": 2, "c": 3}`,
@@ -1164,6 +1173,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'function_call',
+                logprobs: null,
                 message: {
                   role: 'assistant',
                   content: null,
@@ -1241,6 +1251,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'function_call',
+                logprobs: null,
                 message: {
                   role: 'assistant',
                   content: null,
@@ -1291,6 +1302,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'function_call',
+                logprobs: null,
                 message: {
                   role: 'assistant',
                   content: null,
@@ -1360,6 +1372,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'stop',
+                logprobs: null,
                 message: {
                   role: 'assistant',
                   content: `it's raining`,
@@ -1436,6 +1449,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'function_call',
+                logprobs: null,
                 delta: {
                   role: 'assistant',
                   content: null,
@@ -2071,6 +2085,7 @@ describe('resource completions', () => {
               {
                 index: 0,
                 finish_reason: 'function_call',
+                logprobs: null,
                 delta: {
                   role: 'assistant',
                   content: null,

src/lib/ChatCompletionStream.ts

@@ -153,13 +153,22 @@ export class ChatCompletionStream
       Object.assign(snapshot, rest);
     }
 
-    for (const { delta, finish_reason, index, ...other } of chunk.choices) {
+    for (const { delta, finish_reason, index, logprobs = null, ...other } of chunk.choices) {
       let choice = snapshot.choices[index];
       if (!choice) {
-        snapshot.choices[index] = { finish_reason, index, message: delta, ...other };
+        snapshot.choices[index] = { finish_reason, index, message: delta, logprobs, ...other };
         continue;
       }
 
+      if (logprobs) {
+        if (!choice.logprobs) {
+          choice.logprobs = logprobs;
+        } else if (logprobs.content) {
+          choice.logprobs.content ??= [];
+          choice.logprobs.content.push(...logprobs.content);
+        }
+      }
+
       if (finish_reason) choice.finish_reason = finish_reason;
       Object.assign(choice, other);
 
@@ -242,7 +251,7 @@ function finalizeChatCompletion(snapshot: ChatCompletionSnapshot): ChatCompletio
   const { id, choices, created, model } = snapshot;
   return {
     id,
-    choices: choices.map(({ message, finish_reason, index }): ChatCompletion.Choice => {
+    choices: choices.map(({ message, finish_reason, index, logprobs }): ChatCompletion.Choice => {
       if (!finish_reason) throw new OpenAIError(`missing finish_reason for choice ${index}`);
       const { content = null, function_call, tool_calls } = message;
       const role = message.role as 'assistant'; // this is what we expect; in theory it could be different which would make our types a slight lie but would be fine.
@@ -251,12 +260,18 @@ function finalizeChatCompletion(snapshot: ChatCompletionSnapshot): ChatCompletio
         const { arguments: args, name } = function_call;
         if (args == null) throw new OpenAIError(`missing function_call.arguments for choice ${index}`);
         if (!name) throw new OpenAIError(`missing function_call.name for choice ${index}`);
-        return { message: { content, function_call: { arguments: args, name }, role }, finish_reason, index };
+        return {
+          message: { content, function_call: { arguments: args, name }, role },
+          finish_reason,
+          index,
+          logprobs,
+        };
       }
       if (tool_calls) {
         return {
           index,
           finish_reason,
+          logprobs,
           message: {
             role,
             content,
@@ -281,7 +296,7 @@ function finalizeChatCompletion(snapshot: ChatCompletionSnapshot): ChatCompletio
           },
         };
       }
-      return { message: { content: content, role }, finish_reason, index };
+      return { message: { content: content, role }, finish_reason, index, logprobs };
     }),
     created,
     model,
@@ -336,6 +351,11 @@ export namespace ChatCompletionSnapshot {
      */
     finish_reason: ChatCompletion.Choice['finish_reason'] | null;
 
+    /**
+     * Log probability information for the choice.
+     */
+    logprobs: ChatCompletion.Choice.Logprobs | null;
+
     /**
      * The index of the choice in the list of choices.
      */

src/resources/beta/threads/runs/steps.ts

@@ -180,7 +180,7 @@ export interface MessageCreationStepDetails {
   message_creation: MessageCreationStepDetails.MessageCreation;
 
   /**
-   * Always `message_creation``.
+   * Always `message_creation`.
    */
   type: 'message_creation';
 }
@@ -269,7 +269,7 @@ export interface RunStep {
   metadata: unknown | null;
 
   /**
-   * The object type, which is always `thread.run.step``.
+   * The object type, which is always `thread.run.step`.
    */
   object: 'thread.run.step';
 

src/resources/chat/chat.ts

@@ -23,6 +23,7 @@ export namespace Chat {
   export import ChatCompletionNamedToolChoice = CompletionsAPI.ChatCompletionNamedToolChoice;
   export import ChatCompletionRole = CompletionsAPI.ChatCompletionRole;
   export import ChatCompletionSystemMessageParam = CompletionsAPI.ChatCompletionSystemMessageParam;
+  export import ChatCompletionTokenLogprob = CompletionsAPI.ChatCompletionTokenLogprob;
   export import ChatCompletionTool = CompletionsAPI.ChatCompletionTool;
   export import ChatCompletionToolChoiceOption = CompletionsAPI.ChatCompletionToolChoiceOption;
   export import ChatCompletionToolMessageParam = CompletionsAPI.ChatCompletionToolMessageParam;