API Keys & IAM Rules
Comprehensive guide to API key management and Identity Access Management (IAM) rules for fine-grained access control
API Keys & IAM Rules
API keys are the primary method for authenticating with the OffRail. This guide covers creating API keys, managing them, and configuring IAM rules for fine-grained access control.
Overview
OffRail provides comprehensive API key management with the following features:
- Basic API Key Management: Create, list, rename, update, and delete API keys
- Usage Limits: Set lifetime and recurring spending limits on individual API keys
- Expiration (TTL): Give a key a time-to-live so it disables itself automatically
- Rotation (Rolling): Replace a key's secret in place without losing its settings or history
- IAM Rules: Fine-grained access control for models, providers, and pricing
- Usage Tracking: Monitor API key usage and costs
- Status Management: Enable/disable keys without deletion
Related key types
This page covers gateway API keys (orl_…), the keys you send to the
gateway as a bearer token. OffRail also issues three other kinds of keys,
each with its own page:
| Key | What it is for |
|---|---|
| Master keys | Manage projects, gateway API keys, IAM rules, and custom models programmatically |
| Provider keys | Bring your own upstream provider credentials so requests bill to your provider account |
| Platform secret keys | Mint end-user sessions from your backend when using the Payments SDK (sk_…) |
Creating API Keys
Via Dashboard
- Navigate to your project in the OffRail dashboard
- Go to the API Keys section
- Click Create API Key
- Provide a description for your key
- Optionally set an all-time usage limit
- Optionally set a recurring usage limit such as
$10 / dayor$500 / month - Optionally set an expiration (TTL) such as
30 minutes,12 hours, or7 days - Click Create
API keys are shown in full only once during creation. Make sure to copy and store them securely.
Programmatically
Gateway API keys can also be created, listed, updated, and deleted without the dashboard using a master key — useful when you provision a key per customer or per environment from your own backend:
curl -X POST https://internal.offrail.ai/v1/master/keys \
-H "Authorization: Bearer $MASTER_KEY" \
-H "Content-Type: application/json" \
-d '{
"projectId": "proj_...",
"description": "Customer ACME — production key",
"periodUsageLimit": "10.00",
"periodUsageDurationValue": 1,
"periodUsageDurationUnit": "day"
}'Usage limits and IAM rules can be configured through the master key API as well. Expiration (TTL) and rotation are currently dashboard-only. See the master key API reference for the full endpoint list.
Using API Keys
Once you have an API key, use it in the Authorization header of your requests:
curl -X POST "https://api.offrail.ai/v1/chat/completions" \
-H "Authorization: Bearer orl_your_api_key_here" \
-H "Content-Type: application/json" \
-d '{
"model": "gpt-4o",
"messages": [{"role": "user", "content": "Hello!"}]
}'Renaming API Keys
A key's name is only a label, so you can change it at any time — from the
dashboard, or with the description field on PATCH /v1/master/keys/{id} — without
affecting the secret, its usage history, limits, or IAM rules.
Disabling/Enabling API Keys
You can disable an API key to stop it from being used, but the key is not deleted and can be re-enabled later.
Rotating (Rolling) API Keys
Rolling a key generates a new secret for the same key and invalidates the old one immediately. Everything else about the key is preserved: its name, usage history and statistics, all-time and recurring limits (including the active period window), IAM rules, and expiration.
Use this when a secret may have been exposed — in a commit, a log, a CI artifact, or a shared environment — and you want to cut off the leaked value without losing the key's spend tracking or access rules.
- Open the API Keys page and pick the key's actions menu
- Choose Roll Key and confirm
- Copy the new secret and update every client that used the old one
The old secret stops working the moment the key is rolled, and the new secret is shown only once. Roll during a window where you can update your clients promptly.
Requests made with the old secret are rejected with a 401 Unauthorized.
Rolling is limited to regular gateway API keys — the auto-generated playground
key cannot be rolled, and Payments SDK platform secret
keys have their own lifecycle.
Expiration (TTL)
You can give an API key a time-to-live (TTL) when you create it. Set how long the key should live — in minutes, hours, or days — and it will be disabled automatically once that time passes. This is ideal for short-lived integrations, demos, CI jobs, and temporary access.
- A key works normally until its expiration time
- Once expired, the gateway rejects requests with that key with a
401 Unauthorized - A background job marks expired keys as inactive, so the dashboard reflects the disabled state
- Keys created without a TTL never expire (the default)
Reactivating an Expired Key
An expired key is paused, not deleted. To bring it back online you must reactivate it with a new future expiration — an expired key cannot be re-enabled while its TTL is still in the past. Keys that have no TTL, or whose TTL is still in the future, can be enabled and disabled freely without setting a new expiration.
Expiration is independent of usage limits. A key can hit its TTL before, or instead of, reaching a spend cap.
Usage Limits
Usage is tracked per API key on the API Keys page. Usage includes both costs from OffRail credits and usage from your own provider keys when applicable, giving you complete visibility into total spending per key.
You can set two independent limits for each key:
- All-time usage limit: A lifetime spend cap
- Recurring usage limit: A spend cap that resets every configured hour, day, week, or month
When a key reaches either limit, requests using that key return 401 Unauthorized until the key is updated or, for recurring limits, the next
usage window starts. This is separate from IAM rule violations, which return
403 Forbidden.
Recurring windows support:
- Minimum duration: 1 hour
- Maximum duration: 12 months
- Units: hour, day, week, month
For the dashboard walkthrough and field-by-field details, see API Keys in Learn.
IAM Rules
IAM (Identity Access Management) rules provide fine-grained access control over what models, providers, and pricing tiers an API key can access.
Rule Types
Model Access Rules
Control access to specific models:
- Allow Models: Only allow access to specific models
- Deny Models: Block access to specific models
Provider Access Rules
Control access to specific providers:
- Allow Providers: Only allow access to specific providers
- Deny Providers: Block access to specific providers
Provider rules can also target your organization's own custom providers. The generic custom entry matches every custom provider, while a custom:<name> entry (offered in the selector for each of your custom providers) matches only the custom provider with that name. Model rules can likewise reference a custom-catalog model as <name>/<model>.
Pricing Rules
Control access based on model pricing:
- Allow Pricing: Set constraints on what pricing tiers are allowed
- Deny Pricing: Block specific pricing tiers
- Free vs Paid: Allow or deny access to free vs paid models
IP Address Rules
IP address rules are available on the Enterprise plan only. Contact us at contact@offrail.ai to enable them for your organization.
Restrict where the API key can be used from by source IP, using CIDR ranges:
- Allow IP Ranges (CIDR): Only permit requests from the listed IPv4/IPv6 CIDRs
- Deny IP Ranges (CIDR): Block requests from the listed IPv4/IPv6 CIDRs
Both IPv4 (e.g. 192.0.2.0/24) and IPv6 (e.g. 2001:db8::/32) ranges are supported, and you can mix both in a single rule. To restrict to a single address, use a /32 (IPv4) or /128 (IPv6) prefix.
The gateway reads the client IP from the first entry in the X-Forwarded-For header (set by the GCP load balancer). When an allow_ip_cidrs rule is configured and the gateway cannot determine the client IP, the request is denied. Invalid CIDR syntax is rejected at rule-creation time with a 400 error.
Combining Multiple Rules
- Allow rules of the same type are unioned: a request passes if it matches any of them. For example, one
allow_modelsrule with["claude-opus-4-6"]and another with["claude-fable-5"]allow both models — exactly as if you had a single rule listing both. - Allow rules of different types are combined with AND: the request must satisfy every configured allow rule type (e.g. the model must be in the allowed models and served by an allowed provider).
- Deny rules always apply: a request matching any deny rule is rejected, regardless of allow rules.
- Moderation is special-cased:
/v1/moderationsruns a fixed moderation model that cannot appear in model allowlists, so only provider and IP rules apply to it — model and pricing rules are skipped.
Member-Level IAM Rules
The same rule types can also be configured per organization member by owners and admins on the Team page (admins cannot modify an owner's rules). Member-level rules act as an organization-wide ceiling for that member:
- A request must pass both the member's rules and the API key's rules. Within each level, rules combine exactly as described above.
- Key rules can only narrow access further — they can never grant anything the member's rules deny. For example, if an admin restricts a member to a single approved provider with an
allow_providersrule, the member can create a key rule allowing only a specific model from that provider, but a key rule allowing any other provider has no effect. - A key with no rules of its own is still fully constrained by its owner's member-level rules.
- Member-level rules apply to all regular API keys created by that member, across every project in the organization.
When a request is denied by a member-level rule, the 403 error message states that the restriction is an organization member IAM rule set by the org admin (rather than the key's own IAM configuration), so key holders know who to contact.
Member-level rules can also be managed programmatically via the master key API, addressing members by membership id or email.
Error Handling
When API keys encounter IAM rule violations, the API returns a 403 with the standard OpenAI error envelope:
{
"error": {
"message": "Access denied: Model gpt-4 is not in the allowed models list",
"type": "invalid_request_error",
"param": null,
"code": "permission_denied"
}
}Common error scenarios:
- Model not allowed by IAM rules
- Provider blocked by IAM rules
- Pricing limits exceeded
- API key disabled or deleted
- API key expired (TTL passed)
- API key rolled, so the old secret is no longer valid
- Usage limit reached
Migration from Legacy Keys
If you have existing API keys without IAM rules:
- Backward Compatibility: Existing keys continue to work without restrictions
- Gradual Migration: Add IAM rules incrementally
- Testing: Test IAM rules in development before applying to production
- Monitoring: Monitor for access denied errors after implementing rules
API keys without IAM rules have unrestricted access to all models and providers.
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