Function calling for Cohere

src/endpoints/backends/chat-completions.js

@@ -5,7 +5,7 @@ const Readable = require('stream').Readable;
 const { jsonParser } = require('../../express-common');
 const { CHAT_COMPLETION_SOURCES, GEMINI_SAFETY, BISON_SAFETY, OPENROUTER_HEADERS } = require('../../constants');
 const { forwardFetchResponse, getConfigValue, tryParse, uuidv4, mergeObjectWithYaml, excludeKeysByYaml, color } = require('../../util');
-const { convertClaudeMessages, convertGooglePrompt, convertTextCompletionPrompt, convertCohereMessages, convertMistralMessages } = require('../../prompt-converters');
+const { convertClaudeMessages, convertGooglePrompt, convertTextCompletionPrompt, convertCohereMessages, convertMistralMessages, convertCohereTools } = require('../../prompt-converters');
 
 const { readSecret, SECRET_KEYS } = require('../secrets');
 const { getTokenizerModel, getSentencepiceTokenizer, getTiktokenTokenizer, sentencepieceTokenizers, TEXT_COMPLETION_MODELS } = require('../tokenizers');
@@ -544,6 +544,7 @@ async function sendCohereRequest(request, response) {
     try {
         const convertedHistory = convertCohereMessages(request.body.messages, request.body.char_name, request.body.user_name);
         const connectors = [];
+        const tools = [];
 
         if (request.body.websearch) {
             connectors.push({
@@ -551,6 +552,12 @@ async function sendCohereRequest(request, response) {
             });
         }
 
+        if (Array.isArray(request.body.tools) && request.body.tools.length > 0) {
+            tools.push(...convertCohereTools(request.body.tools));
+            // Can't have both connectors and tools in the same request
+            connectors.splice(0, connectors.length);
+        }
+
         // https://docs.cohere.com/reference/chat
         const requestBody = {
             stream: Boolean(request.body.stream),
@@ -569,8 +576,7 @@ async function sendCohereRequest(request, response) {
             prompt_truncation: 'AUTO_PRESERVE_ORDER',
             connectors: connectors,
             documents: [],
-            tools: [],
-            tool_results: [],
+            tools: tools,
             search_queries_only: false,
         };
 

src/prompt-converters.js

@@ -451,6 +451,76 @@ function convertTextCompletionPrompt(messages) {
     return messageStrings.join('\n') + '\nassistant:';
 }
 
+/**
+ * Convert OpenAI Chat Completion tools to the format used by Cohere.
+ * @param {object[]} tools OpenAI Chat Completion tool definitions
+ */
+function convertCohereTools(tools) {
+    if (!Array.isArray(tools) || tools.length === 0) {
+        return [];
+    }
+
+    const jsonSchemaToPythonTypes = {
+        'string': 'str',
+        'number': 'float',
+        'integer': 'int',
+        'boolean': 'bool',
+        'array': 'list',
+        'object': 'dict',
+    };
+
+    const cohereTools = [];
+
+    for (const tool of tools) {
+        if (tool?.type !== 'function') {
+            console.log(`Unsupported tool type: ${tool.type}`);
+            continue;
+        }
+
+        const name = tool?.function?.name;
+        const description = tool?.function?.description;
+        const properties = tool?.function?.parameters?.properties;
+        const required = tool?.function?.parameters?.required;
+        const parameters = {};
+
+        if (!name) {
+            console.log('Tool name is missing');
+            continue;
+        }
+
+        if (!description) {
+            console.log('Tool description is missing');
+        }
+
+        if (!properties || typeof properties !== 'object') {
+            console.log(`No properties found for tool: ${tool?.function?.name}`);
+            continue;
+        }
+
+        for (const property in properties) {
+            const parameterDefinition = properties[property];
+            const description = parameterDefinition.description || (parameterDefinition.enum ? JSON.stringify(parameterDefinition.enum) : '');
+            const type = jsonSchemaToPythonTypes[parameterDefinition.type] || 'str';
+            const isRequired = Array.isArray(required) && required.includes(property);
+            parameters[property] = {
+                description: description,
+                type: type,
+                required: isRequired,
+            };
+        }
+
+        const cohereTool = {
+            name: tool.function.name,
+            description: tool.function.description,
+            parameter_definitions: parameters,
+        };
+
+        cohereTools.push(cohereTool);
+    }
+
+    return cohereTools;
+}
+
 module.exports = {
     convertClaudePrompt,
     convertClaudeMessages,
@@ -458,4 +528,5 @@ module.exports = {
     convertTextCompletionPrompt,
     convertCohereMessages,
     convertMistralMessages,
+    convertCohereTools,
 };