Glossary
Blast radius
How far the effects of an action reach if it goes wrong, from read-only, to a local reversible write, to production or external side effects.
Checks run on our GPUs in Switzerland. Request payloads are not stored.Security
What Blast radius means
Blast radius describes how much damage an action could do if it turns out to be a mistake. It is a property of the action and its target, separate from whether the action is likely to be wrong.
MCP Guard’s blast_radius head uses three ordered levels:
- read-only: nothing changes.
- local or reversible write: a change that is contained or easy to undo, such as editing a file in a working tree.
- production-mutating or external side effect: changes to live systems, or effects outside your control such as an email sent or a payment made.
Blast radius is useful for policy because it lets you spend human attention where it matters. A common pattern is to allow read-only calls freely, allow reversible writes unless other scores are high, and ask before production or external effects. See destructive action and approval fatigue.
Related terms
How Blast radius connects to the rest of the vocabulary.