NexusAPI v3 — Complete Developer Reference

Last updated: January 2025 | Version: 3.4.2 | Base URL: https://api.nexus.io/v3

1. Authentication

NexusAPI uses OAuth 2.0 Bearer tokens for all API calls. Tokens expire after 3600 seconds (1 hour). Refresh tokens are valid for 30 days. API keys for server-to-server communication are available on the Pro plan and above.

1.1 Token Endpoint

POST to /auth/token with your client_id and client_secret.

1.2 Rate Limits by Plan

Rate Limits per Plan Tier
PlanRequests/minuteRequests/dayBurst LimitPrice/month
Free6010,000100$0
Starter300100,000500$49
Pro1,000500,0002,000$199
Enterprise10,000Unlimited20,000Custom

2. Core Endpoints

2.1 Documents API

Document Endpoints
MethodEndpointDescriptionAuth RequiredRate Limit
GET/documentsList all documentsYesStandard
POST/documentsUpload a new documentYes10/min
GET/documents/{id}Get document by IDYesStandard
DELETE/documents/{id}Delete documentYes (Owner)Standard
POST/documents/{id}/parseTrigger AI parsingYes5/min
GET/documents/{id}/sectionsGet parsed sectionsYesStandard

2.2 Search API

Search Endpoints
MethodEndpointDescriptionMax Results
POST/searchFull-text semantic search100
POST/search/hybridBM25 + vector hybrid search50
GET/search/suggestAutocomplete suggestions10

3. Error Codes

All errors follow RFC 7807 Problem Details format.

HTTP Error Code Reference
CodeNameCommon CauseResolution
400Bad RequestInvalid JSON or missing required fieldCheck request body schema
401UnauthorizedMissing or expired tokenRefresh access token
403ForbiddenInsufficient permissionsCheck plan limits or ownership
404Not FoundResource ID does not existVerify document/resource ID
429Too Many RequestsRate limit exceededImplement exponential backoff
500Internal Server ErrorPlatform errorRetry after 30s, contact support
503Service UnavailablePlanned maintenanceCheck status.nexus.io

4. Webhooks

NexusAPI supports webhooks for async notifications. Register a URL via POST /webhooks. Payloads are signed with HMAC-SHA256 using your webhook secret. You must respond with HTTP 200 within 10 seconds or the delivery is retried up to 5 times with exponential backoff starting at 30 seconds.

4.1 Webhook Events

Available Webhook Events
EventTriggerPayload Size (max)
document.parsedAI parsing completes64 KB
document.deletedDocument removed4 KB
search.completedAsync search done256 KB
quota.warning80% of daily quota used4 KB
quota.exceededDaily quota exhausted4 KB

5. SDKs & Libraries

Official SDKs are available for Python, JavaScript/TypeScript, Go, and Java. Community-maintained SDKs exist for Ruby, PHP, and Rust.

Official SDK Versions
LanguagePackageLatest VersionMin Runtime
Pythonnexus-sdk3.4.1Python 3.9+
JavaScript@nexus/sdk3.4.2Node 18+
Gogithub.com/nexus-io/sdk-go3.3.0Go 1.21+
Javaio.nexus:nexus-sdk3.2.1Java 17+