@anvia/logger

Send Anvia agent lifecycle events to your application logs. Choose structured console output or Pino, with child loggers, file destinations, and explicit flushing for shutdown.

Install

pnpm add @anvia/logger @anvia/core @anvia/openai

The quickstart uses OpenAI as the model provider. Pino is included as a dependency.

Quickstart

Set OPENAI_API_KEY in your server environment:

import { Agent } from "@anvia/core";
import { createLoggerObserver, createPinoLogger } from "@anvia/logger";
import { OpenAIClient } from "@anvia/openai";

const logger = createPinoLogger({ name: "support-app", level: "info" });
const apiKey = process.env.OPENAI_API_KEY;
if (!apiKey) throw new Error("Set OPENAI_API_KEY.");
const client = new OpenAIClient({ apiKey });
const agent = new Agent({
  id: "support",
  model: client.completionModel({ modelId: "gpt-5", api: "responses" }),
  instructions: "Answer support questions clearly.",
  observability: { observers: { logger: createLoggerObserver({ logger }) } },
});

try {
  const result = await agent.generate({ prompt: "How do I reset my password?" });
  if (result.type === "response") console.log(result.output);
} finally {
  await logger.flush();
}

The observer omits final outputs, full model requests and responses, and tool results by default. Opt in to additional payloads only when they belong in your application's logs.

Capabilities

• Console and Pino adapters with named, leveled, structured logs.
• Agent run, generation, tool, and retry events through createLoggerObserver.
• Child loggers that inherit context and support flush().
• JSON file output with directory creation, append mode, and synchronous or buffered writes.
• Structured error serialization with bounded cause traversal and opt-in error stacks.

Pass filePath: "logs/app.log" to createPinoLogger for file output. File writes are synchronous by default; when using sync: false, await flush() before shutdown. Flush guarantees depend on the destination, as described in the guide.

Learn more

• Logger options and file durability
• Core observability and agents