Errors

The SDK surfaces failures three ways:

The codes themselves are on errors. This page is how the SDK reports them.

import Mynth, { MynthAPIError, TaskAsyncTaskFailedError } from "@mynthio/sdk";

const mynth = new Mynth();

const pending = await mynth.image
  .generateAsync({
    model: "black-forest-labs/flux.2-pro",
    prompt: "A lighthouse at dusk, film grain",
  })
  .catch((error: unknown) => {
    if (error instanceof MynthAPIError && error.code === "insufficient_balance") {
      // rejected at create: nothing queued, nothing held
    }
    throw error;
  });

try {
  const task = await pending.wait();
  console.log(task.urls[0]);
} catch (error) {
  if (error instanceof TaskAsyncTaskFailedError) {
    // read GET /tasks/{pending.id} for errors[].code
  }
  throw error;
}

Keep the id from generateAsync() before you wait. When generate() throws, the task id is only in the error message, and the error classes have no taskId property.

MynthAPIError

Thrown for any non-2xx response on a create, upload, estimate, or models call.

message says what to change, so it is safe to show as it is. When a field failed the schema, issues has the same problems one by one, with path pointing into the request body:

try {
  await mynth.image.generate({
    model: "black-forest-labs/flux.2-pro",
    prompt: "A lighthouse at dusk",
    count: 50,
  });
} catch (error) {
  if (error instanceof MynthAPIError && error.code === "validation_error") {
    for (const issue of error.issues ?? []) {
      console.error(issue.path.join("."), issue.message);
      // count count must be at most 20 (was 50)
    }
  }
  throw error;
}

A validation error that is not about one field, such as a size the model cannot produce, has no issues. See validation errors.

Two failures are not MynthAPIError:

• A missing API key throws a plain Error when you first read mynth.image or mynth.video.
• A network failure on the create request throws whatever fetch throws. The create is not retried. There are no idempotency keys, so check GET /tasks before you resend a create that may have gone through.

Errors while waiting

All are exported from @mynthio/sdk, and none carries a task error code.

For TaskAsyncTaskFailedError, read GET /tasks/{id}. Its errors array is [{ code, message? }]. Branch on code.

After TaskAsyncTimeoutError the task is still running on Mynth. Read it by id later instead of creating it again.

restricted_content

A provider refusal usually fails one output, not the task. wait() returns, and urls is shorter than count. Read failures for each code. If the refusal failed the whole task, wait() throws TaskAsyncTaskFailedError, and the code is on GET /tasks/{id}. Prompts and images explains the refusal.

Next steps

• Tasks and polling: the poll budget behind TaskAsyncTimeoutError.
• Errors: every HTTP and task code.