diff --git a/codex-rs/config/src/marketplace_edit.rs b/codex-rs/config/src/marketplace_edit.rs
index 24a0208432..c1b0b82030 100644
--- a/codex-rs/config/src/marketplace_edit.rs
+++ b/codex-rs/config/src/marketplace_edit.rs
@@ -2,6 +2,7 @@ use std::fs;
 use std::io::ErrorKind;
 use std::path::Path;
 
+use codex_utils_path::paths_match_after_normalization;
 use toml_edit::DocumentMut;
 use toml_edit::Item as TomlItem;
 use toml_edit::Table as TomlTable;
@@ -89,7 +90,9 @@ fn upsert_marketplace(
     let Some(marketplaces_item) = root.get_mut("marketplaces") else {
         return;
     };
-    if !marketplaces_item.is_table() {
+    if let Some(inline) = marketplaces_item.as_inline_table() {
+        *marketplaces_item = TomlItem::Table(inline.clone().into_table());
+    } else if !marketplaces_item.is_table() {
         *marketplaces_item = TomlItem::Table(new_implicit_table());
     }
 
@@ -98,6 +101,19 @@ fn upsert_marketplace(
     };
     let mut entry = TomlTable::new();
     entry.set_implicit(false);
+    if let Some(existing) = marketplaces.get(marketplace_name)
+        && existing.get("source_type").and_then(TomlItem::as_str) == Some(update.source_type)
+        && existing
+            .get("source")
+            .and_then(TomlItem::as_str)
+            .is_some_and(|source| match update.source_type {
+                "local" => paths_match_after_normalization(source, update.source),
+                _ => source == update.source,
+            })
+        && let Some(auto_update) = existing.get("auto_update")
+    {
+        entry["auto_update"] = auto_update.clone();
+    }
     entry["source_type"] = value(update.source_type.to_string());
     entry["source"] = value(update.source.to_string());
     if let Some(ref_name) = update.ref_name {
@@ -215,6 +231,73 @@ mod tests {
         assert!(marketplace.get("last_revision").is_none());
     }
 
+    #[test]
+    fn readding_a_marketplace_keeps_auto_update_only_for_the_same_source() {
+        let codex_home = TempDir::new().unwrap();
+        let path = codex_home.path().join(CONFIG_TOML_FILE);
+        let original = "https://example.com/team.git";
+        let replacement = "https://example.com/other.git";
+        let existing = format!(
+            r#"marketplaces = {{ team = {{ source_type = "git", source = "{original}", auto_update = true }} }}"#
+        );
+        for (source, expected) in [(original, Some(true)), (replacement, None)] {
+            fs::write(&path, &existing).unwrap();
+            record_user_marketplace(
+                codex_home.path(),
+                "team",
+                &MarketplaceConfigUpdate {
+                    source_type: "git",
+                    source,
+                    ref_name: None,
+                    sparse_paths: &[],
+                },
+            )
+            .unwrap();
+
+            let config: toml::Value = toml::from_str(&fs::read_to_string(&path).unwrap()).unwrap();
+            assert_eq!(
+                config["marketplaces"]["team"]
+                    .get("auto_update")
+                    .and_then(toml::Value::as_bool),
+                expected
+            );
+        }
+    }
+
+    #[test]
+    fn readding_a_local_marketplace_keeps_auto_update_for_an_equivalent_path() {
+        let codex_home = TempDir::new().unwrap();
+        let catalog = codex_home.path().join("catalog");
+        fs::create_dir_all(&catalog).unwrap();
+        let alias = catalog.join("..").join("catalog");
+        let config_path = codex_home.path().join(CONFIG_TOML_FILE);
+        let source = toml::Value::String(alias.to_string_lossy().into_owned());
+        fs::write(
+            &config_path,
+            format!("[marketplaces.team]\nsource_type = 'local'\nsource = {source}\nauto_update = true\n"),
+        )
+        .unwrap();
+
+        record_user_marketplace(
+            codex_home.path(),
+            "team",
+            &MarketplaceConfigUpdate {
+                source_type: "local",
+                source: catalog.to_str().unwrap(),
+                ref_name: None,
+                sparse_paths: &[],
+            },
+        )
+        .unwrap();
+
+        let config: toml::Value =
+            toml::from_str(&fs::read_to_string(config_path).unwrap()).unwrap();
+        assert_eq!(
+            config["marketplaces"]["team"]["auto_update"].as_bool(),
+            Some(true)
+        );
+    }
+
     #[test]
     fn remove_user_marketplace_removes_requested_entry() {
         let codex_home = TempDir::new().unwrap();
diff --git a/codex-rs/config/src/types.rs b/codex-rs/config/src/types.rs
index fc1729ac08..eb511b87ab 100644
--- a/codex-rs/config/src/types.rs
+++ b/codex-rs/config/src/types.rs
@@ -1278,6 +1278,9 @@ where
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq, Default, JsonSchema)]
 #[schemars(deny_unknown_fields)]
 pub struct MarketplaceConfig {
+    /// Check for updates to installed Git plugins from this marketplace when plugins are listed.
+    #[serde(default)]
+    pub auto_update: bool,
     /// Last time Codex successfully added or refreshed this marketplace.
     #[serde(default)]
     pub last_updated: Option<String>,
diff --git a/codex-rs/core-plugins/src/marketplace_upgrade.rs b/codex-rs/core-plugins/src/marketplace_upgrade.rs
index 6890433c15..22d94128c4 100644
--- a/codex-rs/core-plugins/src/marketplace_upgrade.rs
+++ b/codex-rs/core-plugins/src/marketplace_upgrade.rs
@@ -225,12 +225,11 @@ fn parse_configured_git_marketplace(
         .try_into::<MarketplaceConfig>()
         .map_err(|err| format!("invalid configured Git marketplace: {err}"))?;
     let MarketplaceConfig {
-        last_updated: _,
-        last_revision: _,
         source_type,
         source,
         ref_name,
         sparse_paths,
+        ..
     } = marketplace;
     if source_type != Some(MarketplaceSourceType::Git) {
         return Ok(None);
diff --git a/codex-rs/core/config.schema.json b/codex-rs/core/config.schema.json
index 11e616e875..5da012eb28 100644
--- a/codex-rs/core/config.schema.json
+++ b/codex-rs/core/config.schema.json
@@ -2748,6 +2748,11 @@
     "MarketplaceConfig": {
       "additionalProperties": false,
       "properties": {
+        "auto_update": {
+          "default": false,
+          "description": "Check for updates to installed Git plugins from this marketplace when plugins are listed.",
+          "type": "boolean"
+        },
         "last_revision": {
           "default": null,
           "description": "Git revision Codex last successfully activated for this marketplace.",