ラーメン屋エージェント

package.json

@@ -13,7 +13,7 @@
     "test:counter": "node --loader ts-node/esm ./tests/counter.ts",
     "test:sortByArea": "node --loader ts-node/esm ./tests/sortByArea.ts",
     "test:sortByDistance": "node --loader ts-node/esm ./tests/sortByDistance.ts",
-    "agents": "tsx ./scripts/agents/index.ts",
+    "agent": "tsx --network-family-autoselection-attempt-timeout=500 ./scripts/agent.ts",
     "site:api.reliefweb.int:fetch": "node --loader ts-node/esm ./scripts/api.reliefweb.int/fetch.ts",
     "site:api.reliefweb.int:update": "node --loader ts-node/esm ./scripts/api.reliefweb.int/update_disasters.ts",
     "site:api.reliefweb.int:extract": "node --loader ts-node/esm ./scripts/api.reliefweb.int/extract.ts",

scripts/agent.ts

@@ -1,8 +1,13 @@
 import { ChatOllama } from "@langchain/ollama";
 import { HumanMessage } from "@langchain/core/messages";
+import { Tool } from "@langchain/core/tools";
+import { BaseChatModel } from "@langchain/core/language_models/chat_models";
 
 // langgraph
-import { loadWikipediaAgent } from "./agents/wikipedia.ts";
+import { createReactAgent } from "@langchain/langgraph/prebuilt";
+
+// tool
+import { OverpassTokyoRamenCount } from "../src/utils/langchain/tools/osm/overpass/tokyo_ramen/index.ts";
 
 const model = new ChatOllama({
   // 速いがツールを使わずに返答しちゃう
@@ -22,12 +27,23 @@ const model = new ChatOllama({
   temperature: 0,
 });
 
-const agent = await loadWikipediaAgent(model);
+export const loadAgent = async (model: BaseChatModel) => {
+  const tools: Array<Tool> = [new OverpassTokyoRamenCount()];
+  const prompt =
+    "You are a specialist of ramen shops. Be sure to use overpass-tokyo-ramen-count tool and reply based on the results. You have up to 10 chances to use tool.";
+  return createReactAgent({
+    llm: model,
+    tools: tools,
+    stateModifier: prompt,
+  });
+};
+
+const agent = await loadAgent(model);
 
 // Use the agent
 const stream = await agent.stream(
   {
-    messages: [new HumanMessage("Who is the president of the United States?")],
+    messages: [new HumanMessage("東京都台東区のラーメン屋の数を教えて")],
   },
   {
     streamMode: "values",

scripts/tool.ts

@@ -0,0 +1,22 @@
+import { OverpassTokyoRamenCount } from "../src/utils/langchain/tools/osm/overpass/tokyo_ramen";
+import { AIMessage } from "@langchain/core/messages";
+
+import { ToolNode } from "@langchain/langgraph/prebuilt";
+
+const tools = [new OverpassTokyoRamenCount()];
+const toolNode = new ToolNode(tools);
+
+const messageWithSingleToolCall = new AIMessage({
+  content: "",
+  tool_calls: [
+    {
+      name: "overpass-tokyo-ramen-count",
+      args: { input: "台東区" },
+      id: "tool_call_id",
+      type: "tool_call",
+    },
+  ],
+});
+
+const res = await toolNode.invoke({ messages: [messageWithSingleToolCall] });
+console.log(res);

src/utils/langchain/tools/osm/overpass/tokyo_ramen/index.ts

@@ -2,10 +2,10 @@ import { Tool } from "langchain/tools";
 
 export class OverpassTokyoRamenCount extends Tool {
   name = "overpass-tokyo-ramen-count";
-  description = `useful for when you need to count number of ramen shops by a name of area. Input: a name of area.`;
+  description = `useful for when you need to count number of ramen shops by a name of area. Input: a name of area in Tokyo in Japanese.`;
 
   async _call(input: string) {
-    console.debug("Tool: OverpassTokyoRamenCount, input:", input);
+    // console.debug("Tool: OverpassTokyoRamenCount, input:", input);
     try {
       const overpassQuery = `[out:json][timeout:30000];
 area["name"="東京都"]->.outer;
@@ -15,22 +15,29 @@ area["name"="${input}"]->.inner;
 );
 out geom;`;
       const queryString = `data=${encodeURIComponent(overpassQuery)}`;
-      const overpassApiUrl = `https://z.overpass-api.de/api/interpreter?${queryString}`;
-      const res = await fetch(overpassApiUrl);
+      const overpassApiUrl = `https://overpass-api.de/api/interpreter`;
 
+      const res = await fetch(overpassApiUrl, {
+        method: "POST",
+        body: queryString,
+        headers: {
+          "Content-Type": "application/json",
+        },
+      });
       const json = await res.json();
 
       if (json.elements.length === 0) {
         return "failed to fetch. change query";
       }
 
       const answer = json.elements.length;
-      console.debug("Tool: OverpassTokyoRamenCount, answer:");
-      console.debug(answer);
-      console.debug("");
+      // console.debug("Tool: OverpassTokyoRamenCount, answer:");
+      // console.debug(answer);
+      // console.debug("");
       return answer;
     } catch (error) {
-      return "I don't know.";
+      console.error("Tool: OverpassTokyoRamenCount, error:", error);
+      return "Error. Please try again.";
     }
   }
 }