Feature Flags
Give Claude control over your features. AI toggles flags, manages rollouts, and responds to incidents in real-time.
Before
You
The new checkout flow is causing errors. Can you disable it quickly?
Claude
I'd like to help, but I don't have access to your feature flags.
I can't see what flags are enabled, who they're rolled out to, or toggle them.
Could you log into your feature flag dashboard and disable it manually?
You
*Scrambles to find LaunchDarkly credentials at 2am...*
After
You
The new checkout flow is causing errors. Can you disable it quickly?
Claude
Let me find and disable that flag...
Using cortex.list_flags
cortex.list_flags(filter: "checkout")
Response
new_checkout_flow
Status: enabled · Rollout: 100% · Since: 2h ago
Found it. new_checkout_flow is enabled for all users. Disabling now...
Using cortex.disable_flag
cortex.disable_flag("new_checkout_flow")
Response
new_checkout_flow disabled
Previous state saved · Can be re-enabled
Done. The new checkout flow is disabled. All users now see the old checkout.
I've also notified Reflex to watch for error rate changes.
Response time: 8 seconds
Without Cortex
With Cortex
Simple Ruby DSL that works with Rails conventions.
if Cortex.enabled?(:new_checkout, user)
render_new_checkout
end
AI agents can query and control flags directly.
cortex.enable_flag("new_checkout")
Flags change instantly, no deploy needed
Roll out to 10% of users, then 50%, then everyone.
cortex.set_rollout("new_checkout", percentage: 10)
When errors spike, AI auto-disables the flag.
Available via MCP (Model Context Protocol)
cortex.list_flags()
"Show me all feature flags"
cortex.enable_flag(name)
"Turn on dark mode"
cortex.disable_flag(name)
"Kill the new checkout"
cortex.set_rollout(name, %)
"Roll out to 25% of users"
One gem. Zero config. Works in 30 seconds.
# Add to your Gemfile
gem 'brainzlab'
# Run bundle
$ bundle install
# That's it. Feature flags are ready.
We're building Cortex right now. Follow along to get early access and help shape the features.