# Logging

Mastra's logging system captures function execution, input data, and output responses in a structured format.

When deploying to Mastra Cloud, logs are shown on the [Logs](https://mastra.ai/docs/mastra-cloud/observability) page. In self-hosted or custom environments, logs can be directed to files or external services depending on the configured transports.

## Configuring logs with `PinoLogger`

When [initializing a new Mastra project](https://mastra.ai/guides/getting-started/quickstart) using the CLI, `PinoLogger` is included by default.

```typescript
import { Mastra } from '@mastra/core/mastra'
import { PinoLogger } from '@mastra/loggers'

export const mastra = new Mastra({
  logger: new PinoLogger({
    name: 'Mastra',
    level: 'info',
  }),
})
```

> **Info:** Visit [PinoLogger](https://mastra.ai/reference/logging/pino-logger) for all available configuration options.

## Logging to observability storage

When [observability](https://mastra.ai/docs/observability/overview) is configured, all logger calls are automatically forwarded to your observability storage. This means every `debug`, `info`, `warn`, `error`, and `trackException` call from your application and from Mastra's internal components appears alongside your traces.

No code changes are required. Mastra wraps the configured logger so that it writes to both the original logger (console, file, or custom transport) and the observability system simultaneously.

### Configuring observability log level

You can control which log levels reach observability storage independently from your console logger. Add a `logging` option to your observability instance configuration:

```typescript
import { Mastra } from '@mastra/core/mastra'
import { PinoLogger } from '@mastra/loggers'
import { Observability, DefaultExporter } from '@mastra/observability'

export const mastra = new Mastra({
  logger: new PinoLogger({ name: 'Mastra', level: 'debug' }),
  observability: new Observability({
    configs: {
      default: {
        serviceName: 'my-app',
        exporters: [new DefaultExporter()],
        logging: {
          enabled: true, // set to false to disable log forwarding
          level: 'info', // minimum level: 'debug' | 'info' | 'warn' | 'error' | 'fatal'
        },
      },
    },
  }),
})
```

In this example, the console logger outputs all levels starting from `debug`, but only `info` and above are written to observability storage. This keeps your storage clean while still having verbose console output during development.

| Option    | Type       | Default   | Description                                                            |
| --------- | ---------- | --------- | ---------------------------------------------------------------------- |
| `enabled` | `boolean`  | `true`    | Set to `false` to disable all log forwarding to observability storage. |
| `level`   | `LogLevel` | `'debug'` | Minimum severity level. Logs below this level are discarded.           |

### Querying logs

Logs written to observability storage are queryable through the Mastra client SDK:

```typescript
import { MastraClient } from '@mastra/client-js'

const client = new MastraClient()

const logs = await client.listLogsVNext({
  filters: { level: 'error' },
  pagination: { page: 1, perPage: 50 },
  orderBy: { field: 'timestamp', direction: 'desc' },
})
```

When using a persistent storage backend like DuckDB or ClickHouse, logs survive restarts and are available for historical analysis.

## Customizing logs

Mastra provides access to a logger instance via the `mastra.getLogger()` method, available inside both workflow steps and tools. The logger supports standard severity levels: `debug`, `info`, `warn`, and `error`.

### Logging from workflow steps

Within a workflow step, access the logger via the `mastra` parameter inside the `execute` function. This allows you to log messages relevant to the step's execution.

```typescript
import { createWorkflow, createStep } from "@mastra/core/workflows";
import { z } from "zod";

const step1 = createStep({
  execute: async ({ mastra }) => {
    const logger = mastra.getLogger();
    logger.info("workflow info log");

    return {
      output: ""
    };
  }
});

export const testWorkflow = createWorkflow({...})
  .then(step1)
  .commit();
```

### Logging from tools

Similarly, tools have access to the logger instance via the `mastra` parameter. Use this to log tool-specific activity during execution.

```typescript
import { createTool } from '@mastra/core/tools'
import { z } from 'zod'

export const testTool = createTool({
  execute: async (inputData, context) => {
    const logger = context?.mastra.getLogger()
    logger?.info('tool info log')

    return {
      output: '',
    }
  },
})
```

### Logging with additional data

Logger methods accept an optional second argument for additional data. Pass a structured object to make logs filterable in observability storage.

```typescript
import { createWorkflow, createStep } from "@mastra/core/workflows";
import { z } from "zod";

const step1 = createStep({
  execute: async ({ mastra }) => {
    const testAgent = mastra.getAgent("testAgent");
    const logger = mastra.getLogger();

    logger.info("workflow info log", { agent: testAgent });

    return {
      output: ""
    };
  }
});

export const testWorkflow = createWorkflow({...})
  .then(step1)
  .commit();
```