Limits & Access

Rate limits, quotas, and access during the Developer Preview.

Developer Preview

ChessGrammar is currently in Developer Preview. The API is fully functional and accessible without authentication. The engine is actively being developed — expect improvements in accuracy, new patterns, and additional endpoints over time.

Rate limits

Limit	Value	Scope
Position analysis	30 requests/minute	Per IP
Game analysis (PGN)	3 per day	Per IP

When a rate limit is exceeded, the API returns HTTP 429:

{"error": "Rate limit exceeded"}

For game analysis:

{"error": "Daily game analysis limit reached. Need more? Contact us."}

No authentication required

During the Developer Preview, no API key or token is needed. Send requests directly to the endpoints.

# This works — no auth headers needed
curl -X POST https://chessgrammar.com/api/v1/extract \
  -H "Content-Type: application/json" \
  -d '{"fen": "..."}'

Best practices

Use L1 for bulk scanning — 30 req/min at ~13ms each is sufficient for scanning hundreds of positions per session
Two-pass analysis — scan with L1 first, then use L2 only on positions where L1 found candidates
Cache results — the API is deterministic; the same FEN always returns the same result
Filter by pattern — use the patterns parameter to reduce response size when you only need specific tactics

Need more?

If you need higher rate limits, bulk analysis, or dedicated access, get in touch. We're working toward General Availability with expanded access tiers.