From 9843d5f1abefc89f2d23253b3fe05a8da8ed9d31 Mon Sep 17 00:00:00 2001
From: "Dylan M. Taylor" <dylan@dylanmtaylor.com>
Date: Fri, 23 Oct 2026 16:57:06 -0400
Subject: [PATCH] Audit: export names, linked-file ids and MCP prompt arguments
 in one pass

---
 crates/engine/src/cmd/fileio/mod.rs | 12 +++++++-----
 crates/engine/src/cmd/links.rs      |  4 +++-
 crates/mcp/src/prompts.rs           | 21 +++++++++++++++++++--
 3 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/crates/engine/src/cmd/fileio/mod.rs b/crates/engine/src/cmd/fileio/mod.rs
index c819b9ae6..8c224aa12 100644
--- a/crates/engine/src/cmd/fileio/mod.rs
+++ b/crates/engine/src/cmd/fileio/mod.rs
@@ -1366,15 +1366,17 @@ pub(crate) fn unique_file_names<'a>(names: impl IntoIterator<Item = (&'a str, St
 /// `names` with `-2`, `-3`… after a name already used (compared without case).
 fn distinct_names(names: impl IntoIterator<Item = String>) -> Vec<String> {
     let mut taken = std::collections::HashSet::new();
+    // The next number to try for each base: a name repeated many times doesn't search the numbers
+    // taken before it.
+    let mut next: std::collections::HashMap<String, usize> = std::collections::HashMap::new();
     names
         .into_iter()
         .map(|base| {
             let mut name = base.clone();
-            for i in 2.. {
-                if taken.insert(name.to_lowercase()) {
-                    break;
-                }
-                name = format!("{base}-{i}");
+            while !taken.insert(name.to_lowercase()) {
+                let n = next.entry(base.to_lowercase()).or_insert(1);
+                *n += 1;
+                name = format!("{base}-{n}");
             }
             name
         })
diff --git a/crates/engine/src/cmd/links.rs b/crates/engine/src/cmd/links.rs
index f74c344e7..e8f122e96 100644
--- a/crates/engine/src/cmd/links.rs
+++ b/crates/engine/src/cmd/links.rs
@@ -182,6 +182,8 @@ pub(crate) fn linked_groups(d: &Document) -> Vec<(String, Vec<u64>)> {
 fn groups(d: &Document, ids: Option<&[NodeId]>) -> Vec<Group> {
     let mut out: Vec<Group> = vec![];
     let mut index: BTreeMap<(String, String, bool), usize> = BTreeMap::new();
+    // Looked up for every linked node: a set, not the list (which may repeat an id many times).
+    let wanted: Option<std::collections::HashSet<NodeId>> = ids.map(|ids| ids.iter().copied().collect());
     let mut add = |link: &LinkInfo, key: &str, document: Option<Shown>, id: Option<NodeId>| {
         let i = *index.entry((link.path.clone(), key.to_string(), document.is_some())).or_insert_with(|| {
             out.push(Group { link: link.clone(), key: key.to_string(), ids: vec![], document });
@@ -193,7 +195,7 @@ fn groups(d: &Document, ids: Option<&[NodeId]>) -> Vec<Group> {
     };
     d.walk(|n| {
         if let Some((l, key, document)) = linked(n)
-            && ids.is_none_or(|ids| ids.contains(&n.id))
+            && wanted.as_ref().is_none_or(|ids| ids.contains(&n.id))
         {
             add(l, key, document, Some(n.id));
         }
diff --git a/crates/mcp/src/prompts.rs b/crates/mcp/src/prompts.rs
index 2dff4486e..0c0a43926 100644
--- a/crates/mcp/src/prompts.rs
+++ b/crates/mcp/src/prompts.rs
@@ -405,7 +405,10 @@ pub fn get(name: &str, args: &Value) -> Result<Value, String> {
         let ids: Vec<&str> = PROMPTS.iter().map(|p| p.name).collect();
         return Err(format!("unknown prompt `{name}` ({})", ids.join("|")));
     };
-    let mut text = flow(p.text);
+    let template = flow(p.text);
+    // (placeholder, value): filled in one pass over the template, so a value that looks like a
+    // placeholder stays as it is.
+    let mut values: Vec<(String, String)> = vec![];
     for a in p.arguments {
         let given = args.get(a.name).filter(|v| !v.is_null()).map(|v| match v {
             Value::String(s) => s.clone(),
@@ -416,7 +419,21 @@ pub fn get(name: &str, args: &Value) -> Result<Value, String> {
             _ if a.required => return Err(format!("prompt `{name}` needs the `{a_name}` argument", a_name = a.name)),
             _ => a.default.to_string(),
         };
-        text = text.replace(&format!("{{{}}}", a.name), &value);
+        values.push((format!("{{{}}}", a.name), value));
+    }
+    let mut text = String::with_capacity(template.len());
+    let mut rest = template.as_str();
+    while let Some(c) = rest.chars().next() {
+        match values.iter().find(|(placeholder, _)| rest.starts_with(placeholder.as_str())) {
+            Some((placeholder, value)) => {
+                text.push_str(value);
+                rest = rest.get(placeholder.len()..).unwrap_or_default();
+            }
+            None => {
+                text.push(c);
+                rest = rest.get(c.len_utf8()..).unwrap_or_default();
+            }
+        }
     }
     Ok(json!({
         "description": p.description,