diff --git a/AGENTS.md b/AGENTS.md
index 1f69544..2cfdb26 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -6,6 +6,10 @@ The live config on the host is deployed by hephaestus from `ansible/roles/agents
 
 The config file may set `extra-config = "<absolute path>"` to layer a second file on top using the same merge rules (scalars replace, vecs append, profiles merge by name). A missing extra file is silently skipped; nesting is not supported (the extra file cannot itself set `extra-config`).
 
+## Supported distros
+
+Ubuntu 24.04 LTS and Debian 13 (trixie) are the oldest distros we support. Before you rely on a feature of bwrap, the kernel or glibc, check that both of them ship a version that has it.
+
 ## Build and test
 
 - `cargo fmt` and `cargo clippy` must pass before every commit.