Abridge Rate Limits
Overview
Abridge enforces rate limits per organization to ensure platform stability across thousands of concurrent clinical encounters. Limits vary by contract tier and are enforced at the org_id level.
Rate Limit Tiers
| Tier | Concurrent Sessions | API Calls/min | Note Generations/min | WebSocket Connections | |------|---------------------|---------------|---------------------|-----------------------| | Pilot | 10 | 60 | 10 | 10 | | Standard | 100 | 600 | 50 | 100 | | Enterprise | 1,000+ | 6,000 | 500 | 1,000 |
Response Headers
X-RateLimit-Limit: 600
X-RateLimit-Remaining: 42
X-RateLimit-Reset: 1711234567
Retry-After: 30
Instructions
Step 1: Rate Limit Aware Client
// src/abridge/rate-limiter.ts
interface RateLimitState {
remaining: number;
limit: number;
resetAt: Date;
retryAfter?: number;
}
class AbridgeRateLimiter {
private state: RateLimitState = {
remaining: Infinity,
limit: Infinity,
resetAt: new Date(),
};
private queue: Array<{ resolve: () => void; reject: (err: Error) => void }> = [];
private processing = false;
updateFromHeaders(headers: Record<string, string>): void {
if (headers['x-ratelimit-remaining']) {
this.state.remaining = parseInt(headers['x-ratelimit-remaining']);
}
if (headers['x-ratelimit-limit']) {
this.state.limit = parseInt(headers['x-ratelimit-limit']);
}
if (headers['x-ratelimit-reset']) {
this.state.resetAt = new Date(parseInt(headers['x-ratelimit-reset']) * 1000);
}
if (headers['retry-after']) {
this.state.retryAfter = parseInt(headers['retry-after']);
}
}
async waitForSlot(): Promise<void> {
if (this.state.remaining > 0) {
this.state.remaining--;
return;
}
// Wait until rate limit resets
const waitMs = Math.max(0, this.state.resetAt.getTime() - Date.now());
console.log(`Rate limited — waiting ${waitMs}ms for reset`);
await new Promise(r => setTimeout(r, waitMs));
this.state.remaining = this.state.limit;
}
get utilizationPercent(): number {
return ((this.state.limit - this.state.remaining) / this.state.limit) * 100;
}
}
export { AbridgeRateLimiter };
Step 2: Concurrent Session Manager
// src/abridge/session-pool.ts
import Bottleneck from 'bottleneck';
// Manage concurrent encounter sessions within org limits
const sessionLimiter = new Bottleneck({
maxConcurrent: 50, // Stay under tier limit
minTime: 100, // 100ms between session creates
reservoir: 50, // Burst capacity
reservoirRefreshInterval: 60000, // Refill every minute
reservoirRefreshAmount: 50,
});
sessionLimiter.on('depleted', () => {
console.warn('Session pool depleted — queuing new sessions');
});
async function createSessionThrottled(
api: any,
patientId: string,
providerId: string,
specialty: string,
): Promise<any> {
return sessionLimiter.schedule(() =>
api.post('/encounters/sessions', {
patient_id: patientId,
provider_id: providerId,
specialty,
encounter_type: 'outpatient',
})
);
}
export { createSessionThrottled, sessionLimiter };
Step 3: 429 Error Handler with Retry-After
// src/abridge/retry-429.ts
import axios, { AxiosError } from 'axios';
async function handleRateLimitedRequest<T>(
requestFn: () => Promise<T>,
maxRetries: number = 5,
): Promise<T> {
for (let attempt = 1; attempt <= maxRetries; attempt++) {
try {
return await requestFn();
} catch (err) {
const axiosErr = err as AxiosError;
if (axiosErr.response?.status !== 429 || attempt === maxRetries) {
throw err;
}
const retryAfter = axiosErr.response.headers['retry-after'];
const waitMs = retryAfter
? parseInt(retryAfter as string) * 1000
: Math.min(1000 * Math.pow(2, attempt), 60000);
console.log(`429 rate limited — retry ${attempt}/${maxRetries} in ${waitMs}ms`);
await new Promise(r => setTimeout(r, waitMs));
}
}
throw new Error('Unreachable');
}
Step 4: Usage Monitoring
// src/abridge/usage-monitor.ts
interface UsageSnapshot {
timestamp: string;
activeSessions: number;
apiCallsThisMinute: number;
noteGenerationsThisMinute: number;
utilizationPercent: number;
}
class UsageMonitor {
private snapshots: UsageSnapshot[] = [];
private apiCallCount = 0;
private noteGenCount = 0;
recordApiCall(): void { this.apiCallCount++; }
recordNoteGeneration(): void { this.noteGenCount++; }
takeSnapshot(activeSessions: number): UsageSnapshot {
const snapshot: UsageSnapshot = {
timestamp: new Date().toISOString(),
activeSessions,
apiCallsThisMinute: this.apiCallCount,
noteGenerationsThisMinute: this.noteGenCount,
utilizationPercent: (activeSessions / 100) * 100, // Adjust per tier
};
this.snapshots.push(snapshot);
this.apiCallCount = 0;
this.noteGenCount = 0;
return snapshot;
}
getAlerts(): string[] {
const latest = this.snapshots.at(-1);
if (!latest) return [];
const alerts: string[] = [];
if (latest.utilizationPercent > 80) alerts.push('Session utilization > 80%');
if (latest.apiCallsThisMinute > 500) alerts.push('API calls approaching limit');
return alerts;
}
}
Output
- Rate-limit-aware API client with header parsing
- Concurrent session pool with Bottleneck throttling
- Automatic 429 retry with Retry-After header support
- Usage monitoring with utilization alerts
Error Handling
| Error | Cause | Solution |
|-------|-------|----------|
| 429 Too Many Requests | Exceeded org rate limit | Use Retry-After header; implement backoff |
| 503 Service Unavailable | Platform-wide throttling | Back off exponentially; check status page |
| Session create rejected | Concurrent session limit | Queue creates with Bottleneck |
Resources
Next Steps
For security configuration, see abridge-security-basics.