Troubleshooting

Problem: relationships object is empty

"relationships": {}

Cause: Missing include parameter.

Solution: Add include=rover,camera to your request:

curl "...?include=rover,camera"

Problem: img_src is empty

"img_src": ""

Cause: The img_src field is deprecated.

Solution: Use the images object instead:

// Old (deprecated)
photo.img_src

// New (correct)
photo.attributes.images.medium  // or small, large, full

Problem: Query returns no photos

Possible causes:

• Filters are too restrictive
• Invalid rover or camera name
• Date range has no photos
• Sol doesn't exist for that rover

Solution: Start with a broad query and add filters one at a time:

# Start broad
curl "...?rovers=curiosity&per_page=5"

# Add filters one by one
curl "...?rovers=curiosity&sol_min=1000&sol_max=1000&per_page=5"
curl "...?rovers=curiosity&sol_min=1000&sol_max=1000&cameras=NAVCAM&per_page=5"

Problem: 401 Unauthorized

Possible causes:

• API key is missing from request
• API key is in the wrong header
• API key has been regenerated (old key is invalid)
• API key is malformed or truncated

Checklist:

• Header name is exactly X-API-Key (case-sensitive)
• Key starts with mv_live_
• Key is 47 characters total
• No extra spaces or quotes around the key

Problem: 429 Too Many Requests

Solutions:

• Check the retryAfter field and wait that many seconds
• Implement exponential backoff
• Use larger page sizes (per_page=100) to reduce total requests
• Cache responses locally
• Use ETags to avoid counting 304 responses

See Rate Limits Guide for optimization tips.

Problem: CORS errors in browser

Cause: API keys should never be exposed in client-side JavaScript.

Solution: Make API calls from your backend server, not the browser:

// DON'T: Client-side JavaScript
// This exposes your API key!
fetch('https://api.marsvista.dev/...', {
  headers: { 'X-API-Key': 'mv_live_xxx' }
});

// DO: Server-side (Next.js API route, Express, etc.)
// app/api/photos/route.ts
export async function GET(request) {
  const response = await fetch('https://api.marsvista.dev/...', {
    headers: { 'X-API-Key': process.env.MARS_VISTA_API_KEY }
  });
  return Response.json(await response.json());
}