diff --git a/.env.example b/.env.example
index bfadfd4..786fc1b 100644
--- a/.env.example
+++ b/.env.example
@@ -27,6 +27,14 @@ MCP_REGISTRY_JWT_PRIVATE_KEY=bb2c6b424005acd5df47a9e2c87f446def86dd740c888ea3efb
 # This should be disabled in prod
 MCP_REGISTRY_ENABLE_ANONYMOUS_AUTH=false
 
+# GitHub OIDC token exchange (for `mcp-publisher login github-oidc`)
+# Expected `aud` claim on incoming GitHub Actions OIDC tokens. Must equal the
+# scheme + host that publishers pass via `--registry` (e.g. `https://registry.example.com`).
+# The publisher CLI derives the audience from `--registry` automatically; the server
+# rejects all OIDC exchanges if this is unset, so set it on every deployment that
+# accepts GitHub Actions publishes.
+MCP_REGISTRY_GITHUB_OIDC_AUDIENCE=
+
 # Google Cloud Identity OIDC configuration for admin access
 # Enable OIDC authentication for @modelcontextprotocol.io admin accounts
 MCP_REGISTRY_OIDC_ENABLED=false
diff --git a/docs/modelcontextprotocol-io/github-actions.mdx b/docs/modelcontextprotocol-io/github-actions.mdx
index 311b28f..0da50cd 100644
--- a/docs/modelcontextprotocol-io/github-actions.mdx
+++ b/docs/modelcontextprotocol-io/github-actions.mdx
@@ -220,6 +220,7 @@ The workflow will run tests, build the package, publish the package to npm, and
 | Error Message | Action |
 | --- | --- |
 | "Authentication failed" | Ensure `id-token: write` permission is set for OIDC, or check secrets. |
+| "invalid audience" | Your `mcp-publisher` binary is too old for this registry deployment. Re-run the install step shown above so you pick up the latest release. |
 | "Package validation failed" | Verify your package successfully published to the package registry (e.g., npm, PyPI), and that your package has the [necessary verification information](./package-types). |
 
 {/* prettier-ignore-end */}
diff --git a/docs/reference/cli/commands.md b/docs/reference/cli/commands.md
index 0f44b7b..e077019 100644
--- a/docs/reference/cli/commands.md
+++ b/docs/reference/cli/commands.md
@@ -72,6 +72,13 @@ mcp-publisher login github-oidc [--registry=URL]
 - Requires `id-token: write` permission in workflow
 - No browser interaction needed
 
+The CLI derives the OIDC `aud` claim from `--registry` (scheme + host, e.g.
+`https://registry.modelcontextprotocol.io`) so tokens are bound to the specific
+deployment they were minted for. Self-hosters must set
+`MCP_REGISTRY_GITHUB_OIDC_AUDIENCE` on the registry to the matching value;
+publishers running an older `mcp-publisher` will fail with `invalid audience`
+and need to upgrade.
+
 Also see [the guide to publishing from GitHub Actions](../../modelcontextprotocol-io/github-actions.mdx).
 
 #### DNS Verification