From 0e1c636b8f0b774f81798af51e27d398d3054fba Mon Sep 17 00:00:00 2001
From: Jean Mertz <git@jeanmertz.com>
Date: Mon, 2 Feb 2026 06:45:34 +0100
Subject: [PATCH 1/2] refactor(cli, mcp): use `HashSet` for active MCP server
 IDs

Update the MCP server configuration logic to use a `HashSet` instead of
a `Vec` when identifying active servers. This change ensures that each
unique MCP server is only processed once, preventing potential duplicate
connections.

The `run_services` method in `jp_mcp` now accepts an owned `HashSet`,
reducing the need for explicit cloning during the service startup loop.
Additionally, this commit fixes a logging bug in the MCP environment
variable loader by correctly using `inspect_err` and formatting the
error output.

Signed-off-by: Jean Mertz <git@jeanmertz.com>
---
 crates/jp_cli/src/ctx.rs    |  7 ++++---
 crates/jp_mcp/src/client.rs | 11 +++++------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/crates/jp_cli/src/ctx.rs b/crates/jp_cli/src/ctx.rs
index c471da58..adb4e608 100644
--- a/crates/jp_cli/src/ctx.rs
+++ b/crates/jp_cli/src/ctx.rs
@@ -1,4 +1,5 @@
 use std::{
+    collections::HashSet,
     io::{self, IsTerminal as _},
     sync::Arc,
 };
@@ -124,7 +125,7 @@ impl Ctx {
     pub(crate) async fn configure_active_mcp_servers(
         &mut self,
     ) -> Result<JoinSet<std::result::Result<(), jp_mcp::Error>>> {
-        let mut server_ids = vec![];
+        let mut server_ids = HashSet::new();
 
         for (name, cfg) in self.config.conversation.tools.iter() {
             if !cfg.enable() {
@@ -145,11 +146,11 @@ impl Ctx {
                 }
             };
 
-            server_ids.push(server_id);
+            server_ids.insert(server_id);
         }
 
         self.mcp_client
-            .run_services(&server_ids, self.handle().clone())
+            .run_services(server_ids, self.handle().clone())
             .await
             .map_err(Into::into)
     }
diff --git a/crates/jp_mcp/src/client.rs b/crates/jp_mcp/src/client.rs
index 4775c1ff..2838f96c 100644
--- a/crates/jp_mcp/src/client.rs
+++ b/crates/jp_mcp/src/client.rs
@@ -174,7 +174,7 @@ impl Client {
 
     pub async fn run_services(
         &mut self,
-        server_ids: &[McpServerId],
+        server_ids: HashSet<McpServerId>,
         handle: Handle,
     ) -> Result<JoinSet<Result<()>>> {
         let mut clients = self.services.write().await;
@@ -195,7 +195,7 @@ impl Client {
         for server_id in server_ids {
             // Determine which servers to start (in configs but not currently
             // active)
-            if clients.contains_key(server_id) {
+            if clients.contains_key(&server_id) {
                 continue;
             }
 
@@ -204,7 +204,6 @@ impl Client {
             joins.spawn({
                 let servers = self.servers.clone();
                 let clients = self.services.clone();
-                let server_id = server_id.clone();
                 async move {
                     let servers = servers.read().await;
                     let server = servers
@@ -243,11 +242,11 @@ impl Client {
                     .iter()
                     .filter_map(|key| {
                         env::var(key)
-                            .inspect(|error| {
+                            .inspect_err(|error| {
                                 warn!(
                                     key,
-                                    error,
-                                    server = %id,
+                                    error = error.to_string(),
+                                    server = id.to_string(),
                                     "Failed to read MCP server environment variable"
                                 );
                             })

From a820765a25361212eeae2d3e58f5ecc7bc0a734f Mon Sep 17 00:00:00 2001
From: Jean Mertz <git@jeanmertz.com>
Date: Mon, 2 Feb 2026 06:50:18 +0100
Subject: [PATCH 2/2] fixup! refactor(cli, mcp): use `HashSet` for active MCP
 server IDs

Signed-off-by: Jean Mertz <git@jeanmertz.com>
---
 crates/jp_mcp/src/client.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/crates/jp_mcp/src/client.rs b/crates/jp_mcp/src/client.rs
index 2838f96c..723db508 100644
--- a/crates/jp_mcp/src/client.rs
+++ b/crates/jp_mcp/src/client.rs
@@ -1,4 +1,11 @@
-use std::{collections::HashMap, env, path::Path, process::Stdio, sync::Arc, time::Duration};
+use std::{
+    collections::{HashMap, HashSet},
+    env,
+    path::Path,
+    process::Stdio,
+    sync::Arc,
+    time::Duration,
+};
 
 use indexmap::IndexMap;
 use jp_config::providers::mcp::{AlgorithmConfig, McpProviderConfig};