Licensing

CritterWatch is part of the JasperFx ecosystem and is distributed under the Business Source License. While the distribution is done through Nuget, CritterWatch requires a commercial site license to "light up" the management features and the features related to AI assisted development.

CritterWatch is free to use in read-only monitoring mode — you can connect any number of services and watch nodes, agents, message routing, projections, and the dead-letter queue without a license key. A commercial license is required for:

• Any administrative / state-changing action — DLQ replay/discard, listener pause/restart, projection pause/rebuild/rewind, agent pinning, node eject, tenant management, ChaosMonkey, and so on.
• The entire MCP server — every CritterWatch MCP tool is license-gated, including the read/diagnostic tools. There is no free MCP tier.

See CritterWatch plans for pricing.

License Configuration

Once you have a license key, configure it in your CritterWatch server's appsettings.json:

{
  "JasperFx": {
    "LicenseKey": "YOUR-LICENSE-KEY-HERE"
  }
}

Or via environment variable:

JASPERFX__LICENSEKEY=YOUR-LICENSE-KEY-HERE

The license key is validated at startup. If the key is invalid or missing for a Professional feature, those features will be disabled with a warning in the logs.

License Tiers

The plan, service limit, and feature set are carried inside the signed license key itself (they are not configured separately). The tiers are:

Capability	Free (unlicensed)	Professional	Enterprise	Trial
Read-only monitoring	✅	✅	✅	✅
Max monitored services	Unlimited	25	Unlimited	Unlimited
State-changing operations¹	❌	✅	✅	✅
MCP server (all tools)²	❌	✅	✅	✅
Alerts	❌	✅	✅	✅
Audit log	❌	✅	✅	✅
Multi-tenancy management	❌	✅	✅	✅
Custom thresholds	❌	✅	✅	✅
Expiry	n/a (perpetual)	dated	dated	short-lived (default 15 days)

¹ State-changing operations include DLQ replay/discard, listener pause/restart, projection pause/rebuild/rewind, agent pinning, node eject, tenant management, and ChaosMonkey. Read-only monitoring is always available, on every tier.

² The MCP server is entirely commercial — every MCP tool is license-gated, including read/diagnostic tools. Unlicensed callers receive a "license missing" response from every tool.

A Trial is functionally identical to Enterprise (unlimited services, all features) but is issued with a short expiry so it lapses automatically.

Expiry behavior

Every paid license carries an expiry date (Free is perpetual). When a license expires, the server falls back to Free-tier functionality — read-only monitoring of unlimited services, with all state-changing operations and the MCP server disabled — while still surfacing the organization name and expiry date in the UI so the lapse is visible. Renew the license to restore full functionality. No restart is required beyond reloading the key.

Open Source

The Wolverine.CritterWatch observer library (the NuGet package installed in monitored services) is MIT-licensed and has no license key requirement. All services can be monitored regardless of the CritterWatch server license tier.

For more information, visit the JasperFx licensing page.