Runtime artifacts are explicit. Salambo does not upload every file in the sandbox automatically; publish only the files that are safe and useful for the user. A sandbox receives these runtime-scoped environment variables during run startup:
VariablePurpose
SALAMBO_ARTIFACT_UPLOAD_URLRun-scoped upload endpoint for generated artifacts.
SALAMBO_ARTIFACT_TOKENBearer token with the artifact.write capability for the current run.
SALAMBO_OUTPUT_DIRRecommended output root, defaulting to /workspace/outputs.
The token is scoped to the current account/run and does not expose storage provider credentials.

​
Upload a file

Use a small helper in your sandbox code instead of hardcoding an endpoint: 
import { readFile } from 'node:fs/promises';
import { basename } from 'node:path';

export async function uploadArtifact(
  filePath: string,
  options: { path: string; contentType?: string },
) {
  const uploadUrl = process.env.SALAMBO_ARTIFACT_UPLOAD_URL;
  const token = process.env.SALAMBO_ARTIFACT_TOKEN;

  if (!uploadUrl || !token) {
    throw new Error('Artifact publishing is not available for this run.');
  }

  const body = await readFile(filePath);
  const response = await fetch(uploadUrl, {
    method: 'POST',
    headers: {
      Authorization: `Bearer ${token}`,
      'Content-Type': options.contentType ?? 'application/octet-stream',
      'x-display-path': options.path,
      'x-file-name': basename(filePath),
    },
    body,
  });

  if (!response.ok) {
    const message = await response.text();
    throw new Error(`Artifact upload failed (${response.status}): ${message}`);
  }
}
Example: 
await uploadArtifact('/workspace/report.pdf', {
  path: '/reports/report.pdf',
  contentType: 'application/pdf',
});

​
Path and size rules

  • Use logical artifact paths such as /report.txt or /reports/summary.json.
  • /workspace/outputs/... remains accepted for compatibility and is normalized to a logical path.
  • Do not publish secrets, credentials, or temporary files.
  • Re-uploading the same logical path replaces the previous artifact metadata for the run.
  • The default maximum artifact size is 100 MB unless the deployment is configured otherwise.
Published files appear in the run UI and are downloadable through the Files API.