Lucidchart's API enforces per-OAuth-token rate limits, with document mutation operations (creating shapes, updating pages, modifying text) throttled more aggressively than read-only document listing. Automations that programmatically generate architecture diagrams or org charts from external data sources can easily exceed write limits when placing dozens of shapes and connectors in a single batch. Image export endpoints carry additional latency due to server-side rendering, making export-heavy workflows the most common throttling bottleneck.
| Endpoint | Limit | Window | Scope |
|---|---|---|---|
| List documents | 120 req | 1 minute | Per OAuth token |
| Get document / pages | 60 req | 1 minute | Per OAuth token |
| Create/update shapes | 30 req | 1 minute | Per OAuth token |
| Export to PNG/PDF | 10 req | 1 minute | Per OAuth token |
| Create document | 15 req | 1 minute | Per OAuth token |
class LucidRateLimiter {
private tokens: number;
private lastRefill: number;
private readonly max: number;
private readonly refillRate: number;
private queue: Array<{ resolve: () => void }> = [];
constructor(maxPerMinute: number) {
this.max = maxPerMinute;
this.tokens = maxPerMinute;
this.lastRefill = Date.now();
this.refillRate = maxPerMinute / 60_000;
}
async acquire(): Promise<void> {
this.refill();
if (this.tokens >= 1) { this.tokens -= 1; return; }
return new Promise(resolve => this.queue.push({ resolve }));
}
private refill() {
const now = Date.now();
this.tokens = Math.min(this.max, this.tokens + (now - this.lastRefill) * this.refillRate);
this.lastRefill = now;
while (this.tokens >= 1 && this.queue.length) {
this.tokens -= 1;
this.queue.shift()!.resolve();
}
}
}
const writeLimiter = new LucidRateLimiter(25);
const exportLimiter = new LucidRateLimiter(8);
async function lucidRetry<T>(
limiter: LucidRateLimiter, fn: () => Promise<Response>, maxRetries = 3
): Promise<T> {
for (let attempt = 0; attempt <= maxRetries; attempt++) {
await limiter.acquire();
const res = await fn();
if (res.ok) return res.json();
if (res.status === 429) {
const retryAfter = parseInt(res.headers.get("Retry-After") || "20", 10);
const jitter = Math.random() * 2000;
await new Promise(r => setTimeout(r, retryAfter * 1000 + jitter));
continue;
}
if (res.status >= 500 && attempt < maxRetries) {
await new Promise(r => setTimeout(r, Math.pow(2, attempt) * 2000));
continue;
}
throw new Error(`Lucidchart API ${res.status}: ${await res.text()}`);
}
throw new Error("Max retries exceeded");
}
async function batchCreateShapes(docId: string, pageId: string, shapes: any[], batchSize = 5) {
const results: any[] = [];
for (let i = 0; i < shapes.length; i += batchSize) {
const batch = shapes.slice(i, i + batchSize);
const batchResults = await Promise.all(
batch.map(shape => lucidRetry(writeLimiter, () =>
fetch(`${LUCID_BASE}/documents/${docId}/pages/${pageId}/shapes`, {
method: "POST", headers,
body: JSON.stringify(shape),
})
))
);
results.push(...batchResults);
if (i + batchSize < shapes.length) await new Promise(r => setTimeout(r, 8000));
}
return results;
}
| Issue | Cause | Fix |
|---|---|---|
| 429 on shape creation | Exceeded 30 writes/min token limit | Batch shapes, space 3s apart |
| 429 on PNG export | Export limit (10/min) is very low | Queue exports with 8s spacing |
| 408 on large document | Export rendering timeout | Request single page, not full doc |
| 401 token expired | OAuth token TTL exceeded | Refresh token before batch operations |
| 409 concurrent edit | Another user editing same page | Retry after 5s with fresh page version |
See lucidchart-performance-tuning.