diff --git a/.agents/skills/develop-maple-proxy/SKILL.md b/.agents/skills/develop-maple-proxy/SKILL.md
index 5bd190dba..ae9f6044b 100644
--- a/.agents/skills/develop-maple-proxy/SKILL.md
+++ b/.agents/skills/develop-maple-proxy/SKILL.md
@@ -37,6 +37,7 @@ Run the credential-free proxy checks through its pinned shell:
 
 ```sh
 nix develop --no-update-lock-file ./proxy -c bash -lc '
+  set -euo pipefail
   cd proxy
   cargo fmt --all -- --check
   cargo clippy --locked --all-targets --all-features -- -D warnings
diff --git a/.agents/skills/validate-maple/SKILL.md b/.agents/skills/validate-maple/SKILL.md
index d7eef15af..7cbbbd1e4 100644
--- a/.agents/skills/validate-maple/SKILL.md
+++ b/.agents/skills/validate-maple/SKILL.md
@@ -160,6 +160,7 @@ Run the proxy's CI-equivalent component checks through its pinned shell:
 
 ```bash
 nix develop --no-update-lock-file ./proxy -c bash -lc '
+  set -euo pipefail
   cd proxy
   cargo fmt --all -- --check
   cargo clippy --locked --all-targets --all-features -- -D warnings
diff --git a/.github/workflows/proxy-rust.yml b/.github/workflows/proxy-rust.yml
index dd8af5397..fe1011395 100644
--- a/.github/workflows/proxy-rust.yml
+++ b/.github/workflows/proxy-rust.yml
@@ -68,6 +68,7 @@ jobs:
       - name: Run credential-free proxy checks
         run: |
           nix develop --no-update-lock-file ./proxy -c bash -lc '
+            set -euo pipefail
             cd proxy
             cargo fmt --all -- --check
             cargo clippy --locked --all-targets --all-features -- -D warnings