API Reference
The FeatureSignals REST API provides programmatic access to all platform features. 104 endpoints across 21 categories — with an interactive playground to try every endpoint from your browser.
Open Interactive PlaygroundBase URL
https://api.featuresignals.com/v1For self-hosted installations, replace with your own API server URL.
Authentication
The API uses two authentication methods:
| Method | Header | Use Case |
|---|---|---|
| JWT Bearer Token | Authorization: Bearer <token> | Management API (Flag Engine, admin) |
| API Key | X-API-Key: <key> | Evaluation API (SDKs, clients) |
See Authentication for details.
API Categories
Every endpoint in the FeatureSignals API, organized by category. Click any category to see detailed endpoint specifications, or use the playground to execute requests directly.
Authentication
13 endpointsLogin, signup, MFA, token management, and email verification.
Flags
11 endpointsCreate, read, update, delete, and manage feature flags across environments.
Evaluation
8 endpointsEvaluate flags for SDKs and client applications at sub-millisecond latency.
Projects
6 endpointsManage projects that organize flags and environments.
Environments
2 endpointsCreate and manage environments (dev, staging, production) within projects.
Segments
2 endpointsDefine user segments for targeted rollouts and A/B experiments.
Approvals
3 endpointsReview and approve flag changes before they go live.
Audit Log
2 endpointsView and export the complete audit trail of all organization actions.
Webhooks
3 endpointsConfigure webhooks for real-time event delivery to external systems.
Team Management
4 endpointsInvite members, manage roles, and configure permissions.
API Keys
3 endpointsCreate, rotate, and revoke API keys for SDK evaluation.
Billing & Usage
14 endpointsManage subscriptions, credits, payment gateways, and view usage.
SSO
8 endpointsConfigure SAML and OIDC single sign-on for your organization.
SCIM
2 endpointsAutomate user provisioning and deprovisioning via SCIM.
Custom Roles
2 endpointsCreate and manage custom roles with fine-grained permissions.
Metrics & Analytics
6 endpointsView evaluation metrics, impression data, and analytics.
Integrations
4 endpointsManage third-party integrations and view delivery logs.
IP Allowlist
1 endpointRestrict API access to specific IP ranges.
Insights
3 endpointsCompare entities, inspect flag evaluations, and view flag insights.
Platform
2 endpointsOnboarding, search, and platform utilities.
User & Data
5 endpointsManage your account, GDPR data export, email preferences, and hints.
Pagination
| Parameter | Default | Max | Description |
|---|---|---|---|
limit | 50 | 100 | Number of items per page |
offset | 0 | — | Number of items to skip |
Paginated responses use a consistent envelope:
{
"data": [ ... ],
"total": 42,
"limit": 50,
"offset": 0,
"has_more": false
}Error Responses
All errors follow a consistent format:
{
"error": "descriptive error message",
"request_id": "correlation-id"
}| Code | Meaning |
|---|---|
400 | Bad request (validation error) |
401 | Unauthorized (missing/invalid auth) |
403 | Forbidden (insufficient permissions) |
404 | Not found |
409 | Conflict (duplicate resource) |
429 | Rate limit exceeded |
500 | Internal server error |
Rate Limiting
| Header | Meaning |
|---|---|
X-RateLimit-Limit | Maximum requests allowed in the current window |
X-RateLimit-Remaining | Requests remaining before the limit is hit |
X-RateLimit-Reset | Unix timestamp when the window resets |