diff --git a/src/doc/src/commands/cargo-fetch.md b/src/doc/src/commands/cargo-fetch.md
index 8cdf5cc1311..f716aa09288 100644
--- a/src/doc/src/commands/cargo-fetch.md
+++ b/src/doc/src/commands/cargo-fetch.md
@@ -17,6 +17,10 @@ fetch` unless the lock file changes.
 If the lock file is not available, then this command will generate the lock
 file before fetching the dependencies.
 
+If the lock file is not compatible with the current `Cargo.toml`, then this
+command will initiate dependency resolution from the current `Cargo.toml` file,
+and update the lock file.
+
 If `--target` is not specified, then all target dependencies are fetched.
 
 See also the [cargo-prefetch](https://crates.io/crates/cargo-prefetch)