You are a constitutional council ranking individual git commits for ownership allocation.

Compare these two commits. Decide which contributed more lasting value to the project.

Judge substance, not spectacle:
- Prefer correct, lasting design and real bugfixes over churn, formatting, renames, or generated noise.
- Prefer clarity and necessity over sheer line count. A small precise change can beat a large diffuse one.
- Do not favor a side merely because its patch is longer or noisier.
- Weight what the change does for the project, not the contributor's name.

Return ONLY a JSON object: {"winner": "A" or "B", "ratio": "N:M", "explanation": "..."}
The explanation must cite concrete differences in the patches (1-3 sentences).

Side A — contributor: tommy-mor
Side A — commit message:
[5350388a] Add pool-scoped voting: /vote?pool=<parent> picks pairs from children.

- /vote now accepts an optional `pool` param (parent item path). When
  provided without left/right, it picks the first unvoted pair from the
  pool's children. When provided alongside left/right, it constrains
  "next pair" navigation to siblings within the pool.
- "vote on children" button appears on item pages with ≥2 children,
  linking to /vote?pool=<item>.
- Pool is threaded through VoteComparePost → success JS so in-page
  morph after voting keeps the pool context for next-pair navigation.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Side A — unified diff (full patch):
diff --git a/server/src/api/ui_html.rs b/server/src/api/ui_html.rs
index 5faa642451d69555cb391974beb0ad22c9355c8c..b79efdb4d52bd445a67f38cbfd61d3507d2b3014 100644
--- a/server/src/api/ui_html.rs
+++ b/server/src/api/ui_html.rs
@@ -193,6 +193,7 @@ async fn dispatch_ui_action(
             ratio_right,
             explanation,
             next,
+            pool,
             form_action,
         } => {
             if form_action != "/ui" {
@@ -239,6 +240,9 @@ async fn dispatch_ui_action(
                         .into_response();
                 }
             };
+            let pool_id = pool.as_deref().and_then(|p| {
+                crate::path_types::ItemId::parse(p.trim()).map(|i| i.normalized_storage())
+            });
             let mut rl = ratio_left.trim().parse::<i32>().unwrap_or(0).max(0);
             let mut rr = ratio_right.trim().parse::<i32>().unwrap_or(0).max(0);
             if rl == 0 && rr == 0 {
@@ -294,6 +298,7 @@ async fn dispatch_ui_action(
                         &thread_tag,
                         &left_id,
                         &right_id,
+                        pool_id.as_ref(),
                         pid.as_str(),
                         post_index,
                     )
diff --git a/server/src/html/garden/pin.rs b/server/src/html/garden/pin.rs
index 5865cfdbc06aeb6555c97380e25591fae6b3d125..1820d7fe7ee167ecbf5ad5124f23b2ab92ffb01f 100644
--- a/server/src/html/garden/pin.rs
+++ b/server/src/html/garden/pin.rs
@@ -79,7 +79,7 @@ pub(super) fn ont_pin_vote_controls(
                         }
                     }
                 } @else {
-                    a class="ont-vote-compare-btn" href=(vote_compare_href(nav, pi, &current, None)) title="Compare and vote" {
+                    a class="ont-vote-compare-btn" href=(vote_compare_href(nav, pi, &current, None, None)) title="Compare and vote" {
                         span class="ont-vote-glyph" aria-hidden="true" { "⚖" }
                         span { "vote" }
                     }
@@ -121,7 +121,7 @@ pub(super) fn child_row_pin_or_vote(
                         if nv == 1 { "" } else { "s" },
                     );
                     @let aria = format!("Vote; {} pairwise {}", nv, if nv == 1 { "vote" } else { "votes" });
-                    a class="ont-garden-vote-ico" href=(vote_compare_href(nav, pi, row_item, None)) title=(tip) aria-label=(aria) {
+                    a class="ont-garden-vote-ico" href=(vote_compare_href(nav, pi, row_item, None, None)) title=(tip) aria-label=(aria) {
                         span class="ont-garden-vote-glyph" aria-hidden="true" { "⚖" }
                         span class="ont-garden-vote-count" { (format!("{}", nv)) }
                     }
diff --git a/server/src/html/garden/render.rs b/server/src/html/garden/render.rs
index 5c3986ca36902f6c9019a4b5590f0b3b9d2cb4ff..bd8cbce059ee789de6e8dc9b6f69f54beee2f994 100644
--- a/server/src/html/garden/render.rs
+++ b/server/src/html/garden/render.rs
@@ -29,6 +29,7 @@ use super::{
     item::{child_depth_from_uri, item_code_label, item_display_path, item_href},
     item_page::{build_item_page_view_model, sibling_nav_markup},
     pin::{child_row_pin_or_vote, ont_pin_vote_controls, pinned_item_from_jar},
+    vote::vote_pool_href,
 };
 
 pub(super) async fn render_scope_view(
@@ -186,12 +187,21 @@ pub(super) async fn render_scope_view(
             }
 
             section class="ont-tab-panel ont-tab-panel-children" {
+                @let total_children = model.child_rankings.component_rankings
+                    .iter().map(|c| c.ranked.len()).sum::<usize>()
+                    + model.child_rankings.unranked_items.len();
                 h3 {
                     "ranked child groups"
                     @if model.child_depth > 1 {
                         " "
                         span class="muted" { (format!("(depth {})", model.child_depth)) }
                     }
+                    @if total_children >= 2 {
+                        " "
+                        a class="ont-vote-children-btn" href=(vote_pool_href(&nav, &model.item)) {
+                            "vote on children"
+                        }
+                    }
                 }
                 @if model.child_rankings.component_rankings.is_empty() {
                     p class="muted" { "no voted pairs yet in this scope" }
diff --git a/server/src/html/garden/tests.rs b/server/src/html/garden/tests.rs
index 6900a6795bcde866a176722149d6378e5127b4c3..c2036fca7752aef63d260e36cfe9649f63b5c550 100644
--- a/server/src/html/garden/tests.rs
+++ b/server/src/html/garden/tests.rs
@@ -105,7 +105,7 @@ fn suggest_next_vote_pair_prefers_unvoted_sibling_pair() {
     let content = content_for_garden_view(&reduced, &ScopeId::Public);
     let a = ItemId::parse("~/topic/a").unwrap().normalized_storage();
     let b = ItemId::parse("~/topic/b").unwrap().normalized_storage();
-    let next = suggest_next_vote_pair(content, &a, &b).expect("next sibling pair");
+    let next = suggest_next_vote_pair(content, &a, &b, None).expect("next sibling pair");
     assert_ne!(
         canonical_edge_items(&next.0, &next.1),
         canonical_edge_items(&a, &b)
diff --git a/server/src/html/garden/vote.rs b/server/src/html/garden/vote.rs
index 1d7fc8aa7436bfa9c1186dfd940a8d751ab7e088..2682cfcbd2f834b56459a02831aa225cffe67c58 100644
--- a/server/src/html/garden/vote.rs
+++ b/server/src/html/garden/vote.rs
@@ -211,14 +211,15 @@ pub(crate) async fn vote_compare_post_success_js(
     _thread_tag: &str,
     left: &ItemId,
     right: &ItemId,
+    pool: Option<&ItemId>,
     _post_id: &str,
     _post_idx: Option<usize>,
 ) -> String {
     let reduced = state.reduced.read().await;
     let content = content_for_garden_view(&reduced, &nav.scope());
     let edge_history = vote_edge_history_markup(content, left, right);
-    let next_pair = suggest_next_vote_pair(content, left, right);
-    let nav_markup = vote_compare_nav_markup(nav, next_pair.as_ref());
+    let next_pair = suggest_next_vote_pair(content, left, right, pool);
+    let nav_markup = vote_compare_nav_markup(nav, next_pair.as_ref(), pool);
     drop(reduced);
     JsBuilder::new()
         .morph_inner_selector("#vote-edge-history-region", edge_history)
@@ -231,27 +232,39 @@ pub(super) fn vote_compare_href(
     left: &ItemId,
     right: &ItemId,
     thread_override: Option<&str>,
+    pool: Option<&ItemId>,
 ) -> String {
     let left_q = urlencoding::encode(left.as_str());
     let right_q = urlencoding::encode(right.as_str());
-    let base = format!(
+    let mut base = format!(
         "{}/vote?left={}&right={}",
         nav.room_path_prefix_for_vote_compare(),
         left_q,
         right_q
     );
     if let Some(t) = thread_override.filter(|s| !s.is_empty()) {
-        format!("{}&thread={}", base, urlencoding::encode(t))
-    } else {
-        base
+        base = format!("{}&thread={}", base, urlencoding::encode(t));
+    }
+    if let Some(p) = pool {
+        base = format!("{}&pool={}", base, urlencoding::encode(p.as_str()));
     }
+    base
+}
+
+pub(super) fn vote_pool_href(nav: &ThreadNav, pool_item_str: &str) -> String {
+    format!(
+        "{}/vote?pool={}",
+        nav.room_path_prefix_for_vote_compare(),
+        urlencoding::encode(pool_item_str)
+    )
 }
 
 fn vote_compare_nav_markup(
     nav: &ThreadNav,
     next_pair: Option<&(ItemId, ItemId)>,
+    pool: Option<&ItemId>,
 ) -> maud::Markup {
-    let next_pair_href = next_pair.map(|(nl, nr)| vote_compare_href(nav, nl, nr, None));
+    let next_pair_href = next_pair.map(|(nl, nr)| vote_compare_href(nav, nl, nr, None, pool));
     html! {
         div class="vote-compare-nav" {
             @if let Some(href) = &next_pair_href {
@@ -267,8 +280,15 @@ pub(super) fn suggest_next_vote_pair(
     content: &ContentState,
     current_left: &ItemId,
     current_right: &ItemId,
+    pool_parent: Option<&ItemId>,
 ) -> Option<(ItemId, ItemId)> {
-    let pool: Vec<ItemId> = if current_left.parent().as_ref().map(|p| p.as_str())
+    let pool: Vec<ItemId> = if let Some(parent) = pool_parent {
+        content
+            .item_children
+            .get(parent)
+            .map(|s| s.iter().cloned().collect())
+            .unwrap_or_default()
+    } else if current_left.parent().as_ref().map(|p| p.as_str())
         == current_right.parent().as_ref().map(|p| p.as_str())
     {
         current_left
@@ -322,10 +342,14 @@ pub(super) fn vote_compare_item_card(
 }
 #[derive(Debug, Deserialize)]
 pub struct VoteCompareQuery {
-    pub left: String,
-    pub right: String,
+    #[serde(default)]
+    pub left: Option<String>,
+    #[serde(default)]
+    pub right: Option<String>,
     #[serde(default)]
     pub thread: Option<String>,
+    #[serde(default)]
+    pub pool: Option<String>,
 }
 
 /// Public pairwise vote UI — `/vote?left=&right=&thread=`.
@@ -376,17 +400,53 @@ async fn vote_compare_inner(
     jar: CookieJar,
     uri: Uri,
 ) -> axum::response::Response {
-    let left = match ItemId::parse(q.left.trim()) {
-        Some(i) => i.normalized_storage(),
-        None => return (StatusCode::NOT_FOUND, "bad left item").into_response(),
+    let pool_id: Option<ItemId> = match q.pool.as_deref() {
+        Some(p) => match ItemId::parse(p.trim()) {
+            Some(i) => Some(i.normalized_storage()),
+            None => return (StatusCode::BAD_REQUEST, "bad pool item").into_response(),
+        },
+        None => None,
     };
-    let right = match ItemId::parse(q.right.trim()) {
-        Some(i) => i.normalized_storage(),
-        None => return (StatusCode::NOT_FOUND, "bad right item").into_response(),
+
+    let (left, right) = match (q.left.as_deref(), q.right.as_deref()) {
+        (Some(l), Some(r)) => {
+            let left = match ItemId::parse(l.trim()) {
+                Some(i) => i.normalized_storage(),
+                None => return (StatusCode::NOT_FOUND, "bad left item").into_response(),
+            };
+            let right = match ItemId::parse(r.trim()) {
+                Some(i) => i.normalized_storage(),
+                None => return (StatusCode::NOT_FOUND, "bad right item").into_response(),
+            };
+            if left == right {
+                return (StatusCode::BAD_REQUEST, "items must differ").into_response();
+            }
+            (left, right)
+        }
+        (None, None) => {
+            let Some(pool) = pool_id.as_ref() else {
+                return (StatusCode::BAD_REQUEST, "provide left+right or pool").into_response();
+            };
+            let reduced = state.reduced.read().await;
+            let content = content_for_garden_view(&reduced, &nav.scope());
+            let children: Vec<ItemId> = content
+                .item_children
+                .get(pool)
+                .map(|s| s.iter().cloned().collect())
+                .unwrap_or_default();
+            if children.len() < 2 {
+                drop(reduced);
+                return (StatusCode::BAD_REQUEST, "pool has fewer than 2 children to compare").into_response();
+            }
+            let pair = suggest_next_pair_in_pool(&content.ranking_group, &children, None);
+            drop(reduced);
+            match pair {
+                Some(p) => p,
+                None => return (StatusCode::BAD_REQUEST, "no pairs available in pool").into_response(),
+            }
+        }
+        _ => return (StatusCode::BAD_REQUEST, "provide both left and right, or just pool").into_response(),
     };
-    if left == right {
-        return (StatusCode::BAD_REQUEST, "items must differ").into_response();
-    }
 
     let reduced = state.reduced.read().await;
     let content = content_for_garden_view(&reduced, &nav.scope());
@@ -409,7 +469,7 @@ async fn vote_compare_inner(
     let left_body = content.item_bodies.get(&left).cloned();
     let right_body = content.item_bodies.get(&right).cloned();
     let item_bodies_for_cards = content.item_bodies.clone();
-    let next_pair = suggest_next_vote_pair(content, &left, &right);
+    let next_pair = suggest_next_vote_pair(content, &left, &right, pool_id.as_ref());
     drop(reduced);
 
     let title = format!(
@@ -432,6 +492,7 @@ async fn vote_compare_inner(
         "ratio_right": {"$form": "ratio_right"},
         "explanation": {"$form": "explanation"},
         "next": next_path,
+        "pool": pool_id.as_ref().map(|p| p.as_str()),
         "form_action": "/ui",
     }))
     .expect("vote compare rpc json");
@@ -456,7 +517,7 @@ async fn vote_compare_inner(
                 Some(&item_bodies_for_cards),
             ))
         }
-        (vote_compare_nav_markup(&nav, next_pair.as_ref()))
+        (vote_compare_nav_markup(&nav, next_pair.as_ref(), pool_id.as_ref()))
         div id="vote-edge-history-region" {
             (edge_history)
         }
diff --git a/server/src/html/ui_action.rs b/server/src/html/ui_action.rs
index dd5294202569454acf9f41b458718700bbf96f39..2589a2cc00bb7b18cd19ebcbb938083122d6921d 100644
--- a/server/src/html/ui_action.rs
+++ b/server/src/html/ui_action.rs
@@ -50,6 +50,9 @@ pub enum HtmlUiAction {
         explanation: String,
         /// Same-origin path after successful post (JS redirect).
         next: String,
+        /// Pool parent item path, if the vote was initiated from a pool URL.
+        #[serde(default)]
+        pool: Option<String>,
         #[serde(default = "default_ui_form_action")]
         form_action: String,
     },


Side B — contributor: tommy-mor
Side B — commit message:
[a888d56c] refactor: centralize path identity in slug-types

Move canonicalization and CanonicalItemUrl into types::paths with
GardenItemUrl, ForumThreadUrl, and TildeOntologyPath for JSON hrefs.
Server canonical_path and path_types re-export slug-types; RPC and
validation build hrefs via those types instead of string helpers.

Made-with: Cursor

Side B — unified diff (full patch):
diff --git a/server/src/api/helpers.rs b/server/src/api/helpers.rs
index 9b71491e9f9efc44a2a4beba09be8f64bd2ff2ee..03b3e77911ccd662bec8635345dafe2593cf242e 100644
--- a/server/src/api/helpers.rs
+++ b/server/src/api/helpers.rs
@@ -4,12 +4,12 @@ use axum::{
     Json,
 };
 use sha2::{Digest, Sha256};
+use slug_types::paths::{CanonicalItemUrl, GardenItemUrl};
 use slug_types::*;
 use std::collections::HashMap;
 
 use crate::{
     canonical_path::canonicalize_item,
-    path_types::CanonicalItemUrl,
     ranking::connected_components_from_voted_pairs,
 };
 
@@ -30,64 +30,6 @@ pub fn now_ms() -> i64 {
     t.as_millis() as i64
 }
 
-/// Serialize a canonical item for JSON: absolute URLs stay as-is; bare paths get a `/` prefix.
-pub fn item_path_for_api(item: &str) -> String {
-    if item.starts_with("http://") || item.starts_with("https://") {
-        item.to_string()
-    } else {
-        format!("/{}", item)
-    }
-}
-
-/// Same as [`item_path_for_api`], but for private rooms ontology items are prefixed with
-/// `/r/{short}/{slug}` so the URL matches the web app (`/r/…/~/…` routes).
-pub fn item_path_for_api_in_room(item: &str, room_wire: &str) -> String {
-    let room = room_wire.trim();
-    if room.is_empty() || room == "public" {
-        return item_path_for_api(item);
-    }
-    let Some((short, slug)) = room.split_once('/') else {
-        return item_path_for_api(item);
-    };
-    if short.is_empty() || slug.is_empty() {
-        return item_path_for_api(item);
-    }
-    let Some(c) = CanonicalItemUrl::parse(item) else {
-        return item_path_for_api(item);
-    };
-    let root = CanonicalItemUrl::ontology_root();
-    let item_norm = c.as_str().trim_end_matches('/');
-    let root_norm = root.as_str().trim_end_matches('/');
-    if let Some(tail) = c.tilde_tail() {
-        return if tail.is_empty() {
-            format!("https://slug.social/r/{short}/{slug}/~")
-        } else {
-            format!("https://slug.social/r/{short}/{slug}/~/{}", tail)
-        };
-    }
-    if item_norm == root_norm {
-        return format!("https://slug.social/r/{short}/{slug}/~");
-    }
-    item_path_for_api(item)
-}
-
-/// Absolute thread URL for forum JSON (`/t/…` vs `/r/…/t/…`).
-pub fn forum_thread_web_url(room_wire: &str, thread_tag: &str) -> String {
-    let room = room_wire.trim();
-    let tag = thread_tag.trim().trim_start_matches('#');
-    if room.is_empty() || room == "public" {
-        format!("https://slug.social/t/{tag}")
-    } else if let Some((short, slug)) = room.split_once('/') {
-        if short.is_empty() || slug.is_empty() {
-            format!("https://slug.social/t/{tag}")
-        } else {
-            format!("https://slug.social/r/{short}/{slug}/t/{tag}")
-        }
-    } else {
-        format!("https://slug.social/t/{tag}")
-    }
-}
-
 /// Resolve an item path as a first-class canonical path.
 pub fn resolve_item(item: &str) -> Result<String, String> {
     let canonical = canonicalize_item(item);
@@ -109,14 +51,12 @@ pub fn parse_parent_specs(parent: Option<&String>) -> Vec<String> {
 }
 
 /// Apply offset+limit pagination to the flattened component rankings.
-/// Items are flattened in component order (largest component first), then unranked last.
-/// Returns (components, unranked_items) after the window.
 pub fn paginate_rankings(
     components: Vec<RankComponent>,
-    unranked_items: Vec<String>,
+    unranked_items: Vec<GardenItemUrl>,
     offset: usize,
     limit: Option<usize>,
-) -> (Vec<RankComponent>, Vec<String>) {
+) -> (Vec<RankComponent>, Vec<GardenItemUrl>) {
     let mut remaining_skip = offset;
     let mut remaining_take = limit.unwrap_or(usize::MAX);
     let mut out_components: Vec<RankComponent> = Vec::new();
@@ -141,7 +81,7 @@ pub fn paginate_rankings(
         });
     }
 
-    let out_unranked: Vec<String> = if remaining_take > 0 {
+    let out_unranked: Vec<GardenItemUrl> = if remaining_take > 0 {
         unranked_items
             .into_iter()
             .skip(remaining_skip)
@@ -183,11 +123,9 @@ pub fn is_pair_voted(group: &crate::reducer::GroupState, a: &str, b: &str) -> bo
     group.voted_pairs.contains(&(i, j))
 }
 
-/// Compute graph connectivity stats for a set of items within the ranking group.
 pub fn compute_connectivity_stats(group: &crate::reducer::GroupState, pool: &[String]) -> ConnectivityStats {
     let n = pool.len();
 
-    // Map pool items to global indices (items not yet in the group get no index)
     let global_idxs: Vec<Option<usize>> = pool
         .iter()
         .map(|it| {
@@ -197,7 +135,6 @@ pub fn compute_connectivity_stats(group: &crate::reducer::GroupState, pool: &[St
         .collect();
     let present: Vec<usize> = global_idxs.iter().filter_map(|x| *x).collect();
 
-    // Build local index mapping for items that exist in the ranking group
     let global_to_local: HashMap<usize, usize> = present
         .iter()
         .enumerate()
@@ -213,7 +150,6 @@ pub fn compute_connectivity_stats(group: &crate::reducer::GroupState, pool: &[St
         }),
     );
 
-    // Items not in the ranking group at all are also isolates
     let items_not_in_group = global_idxs.iter().filter(|x| x.is_none()).count();
 
     let num_components = comps.len() + isolates.len() + items_not_in_group;
@@ -237,52 +173,3 @@ pub fn vote_touches_path(a: &str, b: &str, parent_canon: &str) -> bool {
     let under = |item: &str| item == parent_canon || item.starts_with(&format!("{}/", parent_canon));
     under(a) || under(b)
 }
-
-#[cfg(test)]
-mod wire_url_tests {
-    use super::{forum_thread_web_url, item_path_for_api_in_room};
-
-    #[test]
-    fn public_room_unchanged() {
-        let u = "https://slug.social/~/a/b";
-        assert_eq!(item_path_for_api_in_room(u, "public"), u);
-    }
-
-    #[test]
-    fn private_room_prefixes_ontology() {
-        assert_eq!(
-            item_path_for_api_in_room("https://slug.social/~/topic/x", "9ab12cd/my-room"),
-            "https://slug.social/r/9ab12cd/my-room/~/topic/x"
-        );
-    }
-
-    #[test]
-    fn private_room_ontology_root() {
-        assert_eq!(
-            item_path_for_api_in_room("https://slug.social/~", "9ab12cd/my-room"),
-            "https://slug.social/r/9ab12cd/my-room/~"
-        );
-        assert_eq!(
-            item_path_for_api_in_room("https://slug.social/~/", "9ab12cd/my-room"),
-            "https://slug.social/r/9ab12cd/my-room/~"
-        );
-    }
-
-    #[test]
-    fn external_url_untouched_in_private_room() {
-        let u = "https://example.com/z";
-        assert_eq!(item_path_for_api_in_room(u, "9ab12cd/my-room"), u);
-    }
-
-    #[test]
-    fn forum_web_public_vs_room() {
-        assert_eq!(
-            forum_thread_web_url("public", "debate"),
-            "https://slug.social/t/debate"
-        );
-        assert_eq!(
-            forum_thread_web_url("9ab12cd/my-room", "#debate"),
-            "https://slug.social/r/9ab12cd/my-room/t/debate"
-        );
-    }
-}
diff --git a/server/src/api/mod.rs b/server/src/api/mod.rs
index 042aa248305f9362a3be78f9eea2a5abf6ba707a..cf22cb0129366c3aed031bc86f3197a4321cb806 100644
--- a/server/src/api/mod.rs
+++ b/server/src/api/mod.rs
@@ -24,8 +24,7 @@ pub use auth::{
 
 pub use helpers::{
     api_error, compute_connectivity_stats, is_pair_voted, now_ms, paginate_rankings,
-    parse_parent_specs, pick_random_distinct, sha256_hex, resolve_item, vote_touches_path,
-    item_path_for_api,
+    parse_parent_specs, pick_random_distinct, resolve_item, sha256_hex, vote_touches_path,
 };
 
 pub use rpc::handle_rpc_batch;
diff --git a/server/src/api/rpc.rs b/server/src/api/rpc.rs
index 5b91f5836625eedbb1cd9423168046e3fb576c17..5f7d50188f1381267402f2e57e671234ef5db2fd 100644
--- a/server/src/api/rpc.rs
+++ b/server/src/api/rpc.rs
@@ -8,6 +8,7 @@ use axum::{
     Json,
 };
 use rand::seq::SliceRandom;
+use slug_types::paths::{ForumThreadUrl, GardenItemUrl, TildeOntologyPath};
 use slug_types::*;
 
 use crate::{
@@ -27,9 +28,8 @@ use crate::{
 
 use super::auth::verify_bearer_principal;
 use super::helpers::{
-    compute_connectivity_stats, forum_thread_web_url, is_pair_voted, item_path_for_api,
-    item_path_for_api_in_room, now_ms, paginate_rankings, parse_parent_specs, pick_random_distinct,
-    resolve_item, vote_touches_path,
+    compute_connectivity_stats, is_pair_voted, now_ms, paginate_rankings, parse_parent_specs,
+    pick_random_distinct, resolve_item, vote_touches_path,
 };
 use super::validate::{normalize_room_and_thread, validate_ingest_document};
 
@@ -184,7 +184,7 @@ fn compute_scope_rank_changes(
         };
         if changed {
             changes.push(RankChange {
-                item: item_path_for_api_in_room(&item, room_wire),
+                item: GardenItemUrl::from_storage_str(&item, room_wire),
                 before: b,
                 after: a,
             });
@@ -206,7 +206,7 @@ fn compute_scope_rank_changes(
         parent: if parent.is_empty() {
             "/".to_string()
         } else {
-            item_path_for_api_in_room(parent, room_wire)
+            GardenItemUrl::from_storage_str(parent, room_wire).into_inner()
         },
         changes,
     })
@@ -302,7 +302,7 @@ fn build_rank_response_for_content(
                     .ranked
                     .into_iter()
                     .map(|r| RankRow {
-                        item: item_path_for_api_in_room(r.item.as_str(), room_wire),
+                        item: GardenItemUrl::from_stored(&r.item, room_wire),
                         percent: if want_percent {
                             Some((r.score / max_score) * 100.0)
                         } else {
@@ -315,10 +315,10 @@ fn build_rank_response_for_content(
         })
         .collect();
 
-    let prefixed_unranked: Vec<String> = rankings
+    let prefixed_unranked: Vec<GardenItemUrl> = rankings
         .unranked_items
         .into_iter()
-        .map(|s| item_path_for_api_in_room(s.as_str(), room_wire))
+        .map(|s| GardenItemUrl::from_stored(&s, room_wire))
         .collect();
 
     let (components, unranked_items) = if offset > 0 || limit.is_some() {
@@ -537,13 +537,13 @@ async fn rpc_post(
         (
             "npx slugsocial public garden pair".to_string(),
             "npx slugsocial public garden rank".to_string(),
-            forum_thread_web_url("public", &thread_id),
+            ForumThreadUrl::from_room_tag("public", &thread_id),
         )
     } else {
         (
             format!("npx slugsocial private {room_key} garden pair"),
             format!("npx slugsocial private {room_key} garden rank"),
-            forum_thread_web_url(&room_key, &thread_id),
+            ForumThreadUrl::from_room_tag(&room_key, &thread_id),
         )
     };
 
@@ -664,7 +664,7 @@ async fn rpc_check(
                         .ranked
                         .into_iter()
                         .map(|r| RankRow {
-                            item: item_path_for_api_in_room(r.item.as_str(), &room_key),
+                            item: GardenItemUrl::from_stored(&r.item, &room_key),
                             score: r.score,
                             percent: None,
                         })
@@ -672,12 +672,12 @@ async fn rpc_check(
                 })
                 .collect();
             CheckScopeRanking {
-                parent: item_path_for_api_in_room(parent.as_str(), &room_key),
+                parent: GardenItemUrl::from_stored(parent, &room_key).into_inner(),
                 components,
                 unranked_items: scoped
                     .unranked_items
                     .into_iter()
-                    .map(|it| item_path_for_api_in_room(it.as_str(), &room_key))
+                    .map(|it| GardenItemUrl::from_stored(&it, &room_key))
                     .collect(),
             }
         })
@@ -687,13 +687,13 @@ async fn rpc_check(
         vec![
             "npx slugsocial public forum post <TAG> --delegate <uuid:rig:model>".to_string(),
             "npx slugsocial public forum list".to_string(),
-            forum_thread_web_url("public", &thread_id),
+            ForumThreadUrl::from_room_tag("public", &thread_id).into_inner(),
         ]
     } else {
         vec![
             format!("npx slugsocial private {room_key} forum post <TAG> --delegate <uuid:rig:model>"),
             format!("npx slugsocial private {room_key} forum list"),
-            forum_thread_web_url(&room_key, &thread_id),
+            ForumThreadUrl::from_room_tag(&room_key, &thread_id).into_inner(),
         ]
     };
 
@@ -717,7 +717,7 @@ fn rpc_list_forum_threads(reduced: &ReducerState, room: &str) -> ThreadsResponse
         .map(|((_, tag), ts)| ThreadSummary {
             thread: format!("#{tag}"),
             last_activity_ts: ts.last_activity_ts,
-            web: forum_thread_web_url(room, tag),
+            web: ForumThreadUrl::from_room_tag(room, tag),
         })
         .collect();
     out.sort_by(|a, b| b.last_activity_ts.cmp(&a.last_activity_ts));
@@ -885,7 +885,7 @@ fn rpc_search(reduced: &ReducerState, q: &str, limit: usize, principal: Option<&
         }
         if score > 0 {
             scored_items.push((score, SearchItemHit {
-                path: item_path_for_api(item.as_str()),
+                path: GardenItemUrl::from_storage_str(item.as_str(), "public"),
                 body: content.item_bodies.get(item).map(|b| snippet_around(b, &words, 120)),
             }));
         }
@@ -1058,8 +1058,8 @@ async fn rpc_get_pair(state: &AppState, room: String, parent_path: String) -> Re
         .collect();
     let cs = compute_connectivity_stats(&content.ranking_group, &pool);
     Ok(RpcResult::Pair(PairResponse {
-        left: item_path_for_api_in_room(&left, &room),
-        right: item_path_for_api_in_room(&right, &room),
+        left: GardenItemUrl::from_storage_str(&left, &room),
+        right: GardenItemUrl::from_storage_str(&right, &room),
         left_body: lb,
         right_body: rb,
         threads: th,
@@ -1137,7 +1137,7 @@ pub async fn handle_rpc_batch(
                 if !content.items.contains(&item) {
                     line_err(
                         "item not found",
-                        Some(format!("{} does not exist", item_path_for_api_in_room(&item_str, &room))),
+                        Some(format!("{} does not exist", GardenItemUrl::from_storage_str(&item_str, &room))),
                     )
                 } else {
                     const MAX_ITEM_BODY: usize = 10_000;
@@ -1160,7 +1160,7 @@ pub async fn handle_rpc_batch(
                         .map(|s| s.iter().cloned().collect())
                         .unwrap_or_default();
                     line_ok(RpcResult::GardenItem(ItemResponse {
-                        item: item_path_for_api_in_room(&item_str, &room),
+                        item: GardenItemUrl::from_storage_str(&item_str, &room),
                         body,
                         truncated,
                         body_len,
@@ -1554,7 +1554,7 @@ pub async fn handle_rpc_batch(
                     for r in items {
                         let pct = want_percent.then(|| ((r.score - bot) / range * 100.0).clamp(0.0, 100.0));
                         ranked.push(RankRow {
-                            item: item_path_for_api_in_room(r.item.as_str(), &room),
+                            item: GardenItemUrl::from_storage_str(r.item.as_str(), &room),
                             score: r.score,
                             percent: pct,
                         });
@@ -1574,7 +1574,7 @@ pub async fn handle_rpc_batch(
                 let page: Vec<RankRow> = ranked
                     .into_iter()
                     .chain(unranked.into_iter().map(|it| RankRow {
-                        item: item_path_for_api_in_room(&it, &room),
+                        item: GardenItemUrl::from_storage_str(&it, &room),
                         score: 0.0,
                         percent: want_percent.then_some(0.0),
                     }))
@@ -1618,7 +1618,7 @@ pub async fn handle_rpc_batch(
                 if !content.items.contains(&item) {
                     line_err(
                         "item not found",
-                        Some(format!("{} does not exist", item_path_for_api_in_room(&item_str, &room))),
+                        Some(format!("{} does not exist", GardenItemUrl::from_storage_str(&item_str, &room))),
                     )
                 } else {
                     let votes: Vec<VoteRow> = content
@@ -1629,8 +1629,8 @@ pub async fn handle_rpc_batch(
                                 .take(limit)
                                 .map(|v| VoteRow {
                                     ts: v.ts,
-                                    a: item_path_for_api_in_room(v.a.as_str(), &room),
-                                    b: item_path_for_api_in_room(v.b.as_str(), &room),
+                                    a: GardenItemUrl::from_stored(&v.a, &room),
+                                    b: GardenItemUrl::from_stored(&v.b, &room),
                                     ratio: format!("{}:{}", v.ratio_left, v.ratio_right),
                                     actor: Some(v.principal.clone()),
                                     body: v.body.clone(),
@@ -1640,7 +1640,7 @@ pub async fn handle_rpc_batch(
                         })
                         .unwrap_or_default();
                     line_ok(RpcResult::Matchup(MatchupResponse {
-                        item: item_path_for_api_in_room(&item_str, &room),
+                        item: GardenItemUrl::from_storage_str(&item_str, &room),
                         votes,
                     }))
                 }
@@ -1667,8 +1667,8 @@ pub async fn handle_rpc_batch(
                                     if a == item_str || b == item_str {
                                         Some(VoteRow {
                                             ts: e.ts,
-                                            a: item_path_for_api_in_room(&a, &room),
-                                            b: item_path_for_api_in_room(&b, &room),
+                                            a: GardenItemUrl::from_storage_str(&a, &room),
+                                            b: GardenItemUrl::from_storage_str(&b, &room),
                                             ratio: format!("{}:{}", ratio_left, ratio_right),
                                             actor: reduced.ingests_by_id.get(&e.post_id).map(|ing| ing.principal.clone()),
                                             body: explanation,
@@ -1704,7 +1704,7 @@ pub async fn handle_rpc_batch(
                     }
                 }).collect();
                 line_ok(RpcResult::RankHistory(RankHistoryResponse {
-                    item: item_path_for_api_in_room(&item_str, &room),
+                    item: GardenItemUrl::from_storage_str(&item_str, &room),
                     history,
                 }))
                 }
@@ -1716,17 +1716,13 @@ pub async fn handle_rpc_batch(
                 } else {
                 let content = content_for_room(&reduced, &room);
                 let parents: HashSet<&str> = content.item_children.keys().map(|s| s.as_str()).collect();
-                let mut paths: Vec<String> = content
+                let mut paths: Vec<GardenItemUrl> = content
                     .items
                     .iter()
                     .filter(|p| !parents.contains(p.as_str()))
-                    .map(|p| p.as_str().to_string())
-                    .collect();
-                paths.sort();
-                let paths: Vec<String> = paths
-                    .into_iter()
-                    .map(|p| item_path_for_api_in_room(&p, &room))
+                    .map(|p| GardenItemUrl::from_stored(p, &room))
                     .collect();
+                paths.sort_by(|a, b| a.as_str().cmp(b.as_str()));
                 line_ok(RpcResult::Leaves(LeavesResponse { paths }))
                 }
             },
@@ -1743,24 +1739,13 @@ pub async fn handle_rpc_batch(
                         let mut v: Vec<PathSummary> = roots.iter()
                             .map(|path| {
                                 let children = content.item_children.get(path.as_str()).map(|s| s.len()).unwrap_or(0);
-                                let path_label = CanonicalItemUrl::parse(path.as_str())
-                                    .and_then(|c| {
-                                        c.tilde_tail().map(|t| {
-                                            if t.is_empty() {
-                                                "~/".to_string()
-                                            } else {
-                                                format!("~/{}", t)
-                                            }
-                                        })
-                                    })
-                                    .unwrap_or_else(|| path.to_string());
                                 PathSummary {
-                                    path: path_label,
+                                    path: TildeOntologyPath::from_stored(path),
                                     children,
-                                    web: item_path_for_api_in_room(path.as_str(), &room),
+                                    web: GardenItemUrl::from_stored(path, &room),
                                 }
                             }).collect();
-                        v.sort_by(|a, b| a.path.cmp(&b.path));
+                        v.sort_by(|a, b| a.path.as_str().cmp(b.path.as_str()));
                         v
                     })
                     .unwrap_or_default();
@@ -1790,8 +1775,8 @@ pub async fn handle_rpc_batch(
                     .take(limit)
                     .map(|v| VoteRow {
                         ts: v.ts,
-                        a: item_path_for_api_in_room(v.a.as_str(), &room),
-                        b: item_path_for_api_in_room(v.b.as_str(), &room),
+                        a: GardenItemUrl::from_stored(&v.a, &room),
+                        b: GardenItemUrl::from_stored(&v.b, &room),
                         ratio: format!("{}:{}", v.ratio_left, v.ratio_right),
                         actor: Some(v.principal.clone()),
                         body: v.body.clone(),
diff --git a/server/src/api/validate.rs b/server/src/api/validate.rs
index 27150577982f52cbd6d11bb93654dc3d4cf75cc5..a51c783ee9785569b5a44c0b1572471fe00d174b 100644
--- a/server/src/api/validate.rs
+++ b/server/src/api/validate.rs
@@ -7,8 +7,9 @@ use crate::{
     path_types::CanonicalItemUrl,
     reducer::{ReducerState, ScopeId},
 };
+use slug_types::paths::GardenItemUrl;
 
-use super::helpers::{item_path_for_api, resolve_item};
+use super::helpers::resolve_item;
 
 #[derive(Debug)]
 pub struct ValidatedIngest {
@@ -22,6 +23,10 @@ pub fn validate_ingest_document(
     text: &str,
     scope: &ScopeId,
 ) -> Result<ValidatedIngest, (StatusCode, String, Option<String>)> {
+    let room_wire = match scope {
+        ScopeId::Public => "public",
+        ScopeId::Room(r) => r.as_str(),
+    };
     let public_content = reduced.public();
     let scoped_content = match scope {
         ScopeId::Public => None,
@@ -61,14 +66,14 @@ pub fn validate_ingest_document(
                 let Some(body_text) = body else {
                     return Err((
                         StatusCode::BAD_REQUEST,
-                        format!("item missing body: {}", item_path_for_api(&item)),
+                        format!("item missing body: {}", GardenItemUrl::from_storage_str(&item, room_wire)),
                         Some("items must be declared with bodies, e.g. `~/path/item { ... }`".to_string()),
                     ));
                 };
                 if body_text.trim().is_empty() {
                     return Err((
                         StatusCode::BAD_REQUEST,
-                        format!("item body is empty: {}", item_path_for_api(&item)),
+                        format!("item body is empty: {}", GardenItemUrl::from_storage_str(&item, room_wire)),
                         Some("write at least one sentence inside `{ ... }`".to_string()),
                     ));
                 }
@@ -101,7 +106,7 @@ pub fn validate_ingest_document(
                         let key = CanonicalItemUrl((*it).clone());
                         !defined_in_doc.contains(*it) && !item_exists(&key)
                     })
-                    .map(|it| item_path_for_api(it))
+                    .map(|it| GardenItemUrl::from_storage_str(it, room_wire).into_inner())
                     .collect();
                 if !missing.is_empty() {
                     return Err((
@@ -119,7 +124,7 @@ pub fn validate_ingest_document(
                         let key = CanonicalItemUrl((*it).clone());
                         !defined_in_doc.contains(*it) && !body_exists(&key)
                     })
-                    .map(|it| item_path_for_api(it))
+                    .map(|it| GardenItemUrl::from_storage_str(it, room_wire).into_inner())
                     .collect();
                 if !missing_body.is_empty() {
                     return Err((
diff --git a/server/src/canonical_path.rs b/server/src/canonical_path.rs
index 5c0febe883d8b3978a25896ed0d71df8509a8717..8a1998025121838b0867f8c5ddbd28aea41a23d2 100644
--- a/server/src/canonical_path.rs
+++ b/server/src/canonical_path.rs
@@ -1,92 +1,3 @@
-//! Normalization for thread tags and ontology item URLs (DSL ↔ stored canonical form).
-//! Not event types — see `events` and `path_types`.
+//! Re-exports — implementations live in `slug-types` (`paths` module).
 
-/// Thread / public tag: stored without leading `#`, lowercase.
-pub fn canonicalize_tag(input: &str) -> String {
-    input.trim().trim_start_matches('#').to_lowercase()
-}
-
-/// Ontology item reference → canonical absolute URL on the slug host.
-pub fn canonicalize_item(input: &str) -> String {
-    let s = input.trim();
-    if s.is_empty() {
-        return String::new();
-    }
-
-    if let Some(rest) = s.strip_prefix("https://") {
-        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
-        let host = host.trim().to_lowercase();
-        if tail.is_empty() {
-            return format!("https://{}", host);
-        } else {
-            return format!("https://{}/{}", host, tail);
-        }
-    }
-    if let Some(rest) = s.strip_prefix("http://") {
-        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
-        let host = host.trim().to_lowercase();
-        if tail.is_empty() {
-            return format!("http://{}", host);
-        } else {
-            return format!("http://{}/{}", host, tail);
-        }
-    }
-
-    let is_tilde = s.starts_with("~/");
-    let rest = s.strip_prefix("~/").or_else(|| s.strip_prefix("/")).unwrap_or(s);
-
-    let tail = rest
-        .split('/')
-        .filter_map(|seg| {
-            let t = seg.trim();
-            if t.is_empty() {
-                None
-            } else {
-                Some(t.to_lowercase())
-            }
-        })
-        .collect::<Vec<_>>()
-        .join("/");
-
-    if is_tilde {
-        format!("https://slug.social/~/{}", tail)
-    } else if tail.is_empty() {
-        "https://slug.social".to_string()
-    } else {
-        format!("https://slug.social/{}", tail)
-    }
-}
-
-pub fn item_path_segments(input: &str) -> Vec<String> {
-    let canonical = canonicalize_item(input);
-    if canonical.is_empty() {
-        return vec![];
-    }
-
-    if let Some(rest) = canonical.strip_prefix("https://") {
-        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
-        let mut out = vec![format!("https://{}", host)];
-        out.extend(tail.split('/').filter(|s| !s.is_empty()).map(|s| s.to_string()));
-        return out;
-    }
-    if let Some(rest) = canonical.strip_prefix("http://") {
-        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
-        let mut out = vec![format!("http://{}", host)];
-        out.extend(tail.split('/').filter(|s| !s.is_empty()).map(|s| s.to_string()));
-        return out;
-    }
-
-    canonical
-        .split('/')
-        .filter(|s| !s.is_empty())
-        .map(|s| s.to_string())
-        .collect()
-}
-
-pub fn item_parent_path(input: &str) -> Option<String> {
-    let segs = item_path_segments(input);
-    if segs.len() <= 1 {
-        return None;
-    }
-    Some(segs[..segs.len() - 1].join("/"))
-}
+pub use slug_types::paths::{canonicalize_item, canonicalize_tag, item_parent_path, item_path_segments};
diff --git a/server/src/html/forum.rs b/server/src/html/forum.rs
index ab7970feca47a4431ddc19dab2c8186180b78413..f789e347dc136f8ffd356f4492f0bd76cea04bf0 100644
--- a/server/src/html/forum.rs
+++ b/server/src/html/forum.rs
@@ -697,7 +697,7 @@ async fn thread_view_inner(
     let offset = q.offset.unwrap_or(0);
     let page_ids: Vec<String> = all_ids.into_iter().skip(offset).take(PAGE_SIZE).collect();
 
-    let (display_ingests, subtitle) = {
+    let (display_ingests, _subtitle) = {
         let reduced = state.reduced.read().await;
         let ingests = page_ids
             .iter()
diff --git a/server/src/path_types.rs b/server/src/path_types.rs
index cad58cac7da948f92d6ea2a5587d917ab21d57ea..4c8075bbd488f1b9a5eda9e03ced83f6238c6d5e 100644
--- a/server/src/path_types.rs
+++ b/server/src/path_types.rs
@@ -1,260 +1,3 @@
-//! Path representation types.
-//!
-//! The codebase currently treats item identifiers as strings in a few different
-//! encodings:
-//! - user/DSL input like `~/a/b`
-//! - canonical item URLs like `https://slug.social/~/a/b`
-//! - relative paths within a rooted tree view (e.g. `llms/openai` under a root)
-//!
-//! This module adds lightweight newtypes so code can be explicit about what it
-//! expects without changing core storage formats.
-//!
-//! **Storage vs wire:** [`CanonicalItemUrl`] values are shared across scopes
-//! (`https://slug.social/~/…`); which [`crate::reducer::ContentState`] they live in
-//! is determined by scope, not by embedding the room id in the string. For JSON/RPC
-//! and browser links in a private room, use [`crate::api::helpers::item_path_for_api_in_room`]
-//! so ontology items become `https://slug.social/r/{short}/{slug}/~/…`.
+//! Re-exports — implementations live in `slug-types` (`paths` module).
 
-use std::borrow::Borrow;
-use std::fmt;
-
-use serde::{Deserialize, Serialize};
-
-use crate::canonical_path::canonicalize_item;
-
-/// Canonical item identifier as produced by `canonical_path::canonicalize_item`.
-///
-/// In practice this is usually:
-/// - `https://slug.social/~/...` for ontology items, or
-/// - `https://...` / `http://...` for URL items.
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
-pub struct CanonicalItemUrl(pub String);
-
-impl CanonicalItemUrl {
-    pub fn parse(input: &str) -> Option<Self> {
-        let c = canonicalize_item(input);
-        if c.is_empty() {
-            None
-        } else {
-            Some(Self(c))
-        }
-    }
-
-    pub fn as_str(&self) -> &str {
-        &self.0
-    }
-
-    /// Returns the `~/...` tail for ontology items (`https://slug.social/~/...`).
-    pub fn tilde_tail(&self) -> Option<&str> {
-        self.0.strip_prefix("https://slug.social/~/")
-    }
-
-    /// Returns the final non-empty `/`-separated segment of the path.
-    ///
-    /// `https://slug.social/~/a/b/c` → `"c"`
-    /// `https://slug.social/~/a`     → `"a"`
-    pub fn last_segment(&self) -> &str {
-        self.0
-            .rsplit('/')
-            .find(|s| !s.is_empty())
-            .unwrap_or(self.0.as_str())
-    }
-
-    /// The ontology root key as stored in `item_children`: `"https://slug.social/~"`.
-    /// Use this (not `parse("~/")`) when looking up top-level children.
-    pub fn ontology_root() -> Self {
-        Self("https://slug.social/~".to_string())
-    }
-
-    /// Returns the parent of this canonical item URL by stripping the last
-    /// path segment, or `None` if there is no parent (already at root).
-    ///
-    /// `https://slug.social/~/a/b/c` → `Some("https://slug.social/~/a/b")`
-    /// `https://slug.social/~/a`     → `Some("https://slug.social/~")`
-    /// `https://slug.social/~/`      → `None`  (tilde root)
-    pub fn parent(&self) -> Option<Self> {
-        // tilde_tail() is None for non-ontology URLs and "" for the root ~/
-        if self.tilde_tail().map(|t| t.is_empty()).unwrap_or(true) {
-            return None;
-        }
-        // Strip everything from the last '/' onwards.
-        let last_slash = self.0.rfind('/')?;
-        let parent_str = &self.0[..last_slash];
-        if parent_str.is_empty() {
-            None
-        } else {
-            Some(Self(parent_str.to_string()))
-        }
-    }
-
-    /// Segments of an ontology path suitable for breadcrumb rendering.
-    /// Strips the `https://slug.social` prefix and returns the `~/…` parts.
-    ///
-    /// `https://slug.social/~/a/b` → `["~", "a", "b"]`
-    /// `https://slug.social/~/`    → `["~"]`
-    pub fn tilde_segments(&self) -> Vec<&str> {
-        match self.tilde_tail() {
-            Some(tail) if !tail.is_empty() => {
-                std::iter::once("~")
-                    .chain(tail.split('/').filter(|s| !s.is_empty()))
-                    .collect()
-            }
-            Some(_) => vec!["~"],
-            None => vec![],
-        }
-    }
-}
-
-impl fmt::Display for CanonicalItemUrl {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-/// Allow `HashMap<CanonicalItemUrl, _>` to be searched by `&str`.
-impl Borrow<str> for CanonicalItemUrl {
-    fn borrow(&self) -> &str {
-        &self.0
-    }
-}
-
-impl PartialEq<str> for CanonicalItemUrl {
-    fn eq(&self, other: &str) -> bool {
-        self.0 == other
-    }
-}
-
-impl PartialEq<&str> for CanonicalItemUrl {
-    fn eq(&self, other: &&str) -> bool {
-        self.0 == *other
-    }
-}
-
-impl PartialEq<String> for CanonicalItemUrl {
-    fn eq(&self, other: &String) -> bool {
-        &self.0 == other
-    }
-}
-
-/// A `~/...` input path (as used in the DSL and UX).
-///
-/// This is not canonicalized; it is a presentation/input form.
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
-pub struct TildePath(pub String);
-
-impl TildePath {
-    pub fn new(input: &str) -> Option<Self> {
-        let s = input.trim();
-        if s.starts_with("~/") && s.len() > 2 {
-            Some(Self(s.to_string()))
-        } else if s == "~/" {
-            Some(Self("~/".to_string()))
-        } else {
-            None
-        }
-    }
-
-    pub fn as_str(&self) -> &str {
-        &self.0
-    }
-
-    pub fn canonicalize(&self) -> Option<CanonicalItemUrl> {
-        CanonicalItemUrl::parse(&self.0)
-    }
-}
-
-impl fmt::Display for TildePath {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-/// A path relative to a chosen root in a tree UI.
-///
-/// This is intended for compact state encodings (blobs). It must be joined to a
-/// root `CanonicalItemUrl` (typically an ontology root) to become a full item.
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
-pub struct RelativePath(pub String);
-
-impl RelativePath {
-    pub fn new(input: &str) -> Option<Self> {
-        let s = input.trim().trim_matches('/');
-        if s.is_empty() {
-            Some(Self(String::new()))
-        } else {
-            // Keep this permissive: the DSL parser is the main gatekeeper.
-            Some(Self(s.to_string()))
-        }
-    }
-
-    pub fn as_str(&self) -> &str {
-        &self.0
-    }
-
-    /// Join this relative path under a canonical ontology root
-    /// (`https://slug.social/~/...`) to form a canonical item URL.
-    pub fn join_under_ontology_root(&self, root: &CanonicalItemUrl) -> Option<CanonicalItemUrl> {
-        let base = root.tilde_tail()?;
-        // base is the tail after https://slug.social/~/, e.g. "models" or "models/llms"
-        let joined = if base.is_empty() {
-            if self.0.is_empty() {
-                "~/".to_string()
-            } else {
-                format!("~/{}", self.0)
-            }
-        } else if self.0.is_empty() {
-            format!("~/{}", base)
-        } else {
-            format!("~/{}/{}", base.trim_end_matches('/'), self.0)
-        };
-        CanonicalItemUrl::parse(&joined)
-    }
-}
-
-impl fmt::Display for RelativePath {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn canonical_parent_deep() {
-        let c = CanonicalItemUrl::parse("~/a/b/c").unwrap();
-        assert_eq!(c.parent().unwrap().as_str(), "https://slug.social/~/a/b");
-    }
-
-    #[test]
-    fn canonical_parent_one_level() {
-        let c = CanonicalItemUrl::parse("~/a").unwrap();
-        assert_eq!(c.parent().unwrap().as_str(), "https://slug.social/~");
-    }
-
-    #[test]
-    fn canonical_parent_root_is_none() {
-        let root = CanonicalItemUrl::parse("~/").unwrap();
-        assert!(root.parent().is_none());
-    }
-
-    #[test]
-    fn tilde_segments_deep() {
-        let c = CanonicalItemUrl::parse("~/a/b").unwrap();
-        assert_eq!(c.tilde_segments(), vec!["~", "a", "b"]);
-    }
-
-    #[test]
-    fn tilde_segments_root() {
-        let c = CanonicalItemUrl::parse("~/").unwrap();
-        assert_eq!(c.tilde_segments(), vec!["~"]);
-    }
-
-    #[test]
-    fn tilde_segments_non_ontology_is_empty() {
-        let c = CanonicalItemUrl::parse("https://example.com/foo").unwrap();
-        assert_eq!(c.tilde_segments(), Vec::<&str>::new());
-    }
-}
+pub use slug_types::paths::{CanonicalItemUrl, RelativePath, TildePath};
diff --git a/types/src/lib.rs b/types/src/lib.rs
index c1cde3b783d03b02783385b5f07659fb112aae3e..5fc867bf2af84c2ca63fa1cdd03413110ad784a3 100644
--- a/types/src/lib.rs
+++ b/types/src/lib.rs
@@ -1,7 +1,13 @@
 use serde::{Deserialize, Serialize};
 
+pub mod paths;
 pub mod timeago;
 
+pub use paths::{
+    canonicalize_item, canonicalize_tag, item_parent_path, item_path_segments, CanonicalItemUrl,
+    ForumThreadUrl, GardenItemUrl, RelativePath, TildeOntologyPath, TildePath,
+};
+
 #[derive(Debug, Serialize, Deserialize)]
 pub struct ApiError {
     pub ok: bool,
@@ -12,7 +18,7 @@ pub struct ApiError {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct RankRow {
-    pub item: String,
+    pub item: GardenItemUrl,
     pub score: f64,
     /// Normalized score as a percentage of the top item (0–100). Present when ?percent=true.
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -43,7 +49,7 @@ pub struct RankComponent {
 #[derive(Debug, Serialize, Deserialize)]
 pub struct RankResponse {
     pub components: Vec<RankComponent>,
-    pub unranked_items: Vec<String>,
+    pub unranked_items: Vec<GardenItemUrl>,
 }
 
 /// Graph connectivity stats for a scope, returned with pair suggestions.
@@ -63,8 +69,8 @@ pub struct ConnectivityStats {
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct PairResponse {
-    pub left: String,
-    pub right: String,
+    pub left: GardenItemUrl,
+    pub right: GardenItemUrl,
     pub left_body: Option<String>,
     pub right_body: Option<String>,
     /// Thread tags that discuss either item (connective tissue to forum).
@@ -79,7 +85,7 @@ pub struct PairResponse {
 pub struct NextMoves {
     pub pair: String,
     pub rank: String,
-    pub web: String,
+    pub web: ForumThreadUrl,
 }
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -90,14 +96,14 @@ pub struct PathsResponse {
 /// Leaf items only (no children). For search / "full path list" — does not scale, works for now.
 #[derive(Debug, Serialize, Deserialize)]
 pub struct LeavesResponse {
-    pub paths: Vec<String>,
+    pub paths: Vec<GardenItemUrl>,
 }
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct PathSummary {
-    pub path: String,
+    pub path: TildeOntologyPath,
     pub children: usize,
-    pub web: String,
+    pub web: GardenItemUrl,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -109,7 +115,7 @@ pub struct ThreadsResponse {
 pub struct ThreadSummary {
     pub thread: String,
     pub last_activity_ts: i64,
-    pub web: String,
+    pub web: ForumThreadUrl,
 }
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -178,7 +184,7 @@ pub struct IngestRow {
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct ItemResponse {
-    pub item: String,
+    pub item: GardenItemUrl,
     pub body: Option<String>,
     /// True when the body was truncated due to size. Fetch with `?full=true` for the complete body.
     #[serde(default, skip_serializing_if = "std::ops::Not::not")]
@@ -201,15 +207,15 @@ pub struct RecentVotesResponse {
 /// Vote history for one item (matchup: wins/losses + thread per vote).
 #[derive(Debug, Serialize, Deserialize)]
 pub struct MatchupResponse {
-    pub item: String,
+    pub item: GardenItemUrl,
     pub votes: Vec<VoteRow>,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct VoteRow {
     pub ts: i64,
-    pub a: String,
-    pub b: String,
+    pub a: GardenItemUrl,
+    pub b: GardenItemUrl,
     pub ratio: String,
     /// Principal username when present (stored form, no `@`).
     pub actor: Option<String>,
@@ -510,7 +516,7 @@ pub struct RankPosition {
 /// How one item's rank changed after a vote.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct RankChange {
-    pub item: String,
+    pub item: GardenItemUrl,
     /// Position before the vote. None = was unranked (no voted connections in this scope).
     pub before: Option<RankPosition>,
     /// Position after the vote. None = became unranked (e.g. component split, unlikely).
@@ -544,7 +550,7 @@ pub struct CheckScopeRanking {
     /// Parent scope path (e.g. "/models" or "/" for root).
     pub parent: String,
     pub components: Vec<RankComponent>,
-    pub unranked_items: Vec<String>,
+    pub unranked_items: Vec<GardenItemUrl>,
 }
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -567,7 +573,7 @@ pub struct SearchResponse {
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct SearchItemHit {
-    pub path: String,
+    pub path: GardenItemUrl,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub body: Option<String>,
 }
@@ -614,7 +620,7 @@ pub struct RankHistoryRow {
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct RankHistoryResponse {
-    pub item: String,
+    pub item: GardenItemUrl,
     pub history: Vec<RankHistoryRow>,
 }
 
diff --git a/types/src/paths.rs b/types/src/paths.rs
new file mode 100644
index 0000000000000000000000000000000000000000..2950a7502255927583fbacdfd2adb700f0b0c221
--- /dev/null
+++ b/types/src/paths.rs
@@ -0,0 +1,498 @@
+//! Canonical paths, storage ids, and JSON href newtypes. All normalization and
+//! room-aware URL rules for items live here.
+
+use std::borrow::Borrow;
+use std::fmt;
+
+use serde::{Deserialize, Serialize};
+
+// ---------------------------------------------------------------------------
+// Normalization (moved from server `canonical_path`)
+// ---------------------------------------------------------------------------
+
+/// Thread / public tag: stored without leading `#`, lowercase.
+pub fn canonicalize_tag(input: &str) -> String {
+    input.trim().trim_start_matches('#').to_lowercase()
+}
+
+/// Ontology item reference → canonical absolute URL on the slug host.
+pub fn canonicalize_item(input: &str) -> String {
+    let s = input.trim();
+    if s.is_empty() {
+        return String::new();
+    }
+
+    if let Some(rest) = s.strip_prefix("https://") {
+        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
+        let host = host.trim().to_lowercase();
+        if tail.is_empty() {
+            return format!("https://{}", host);
+        } else {
+            return format!("https://{}/{}", host, tail);
+        }
+    }
+    if let Some(rest) = s.strip_prefix("http://") {
+        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
+        let host = host.trim().to_lowercase();
+        if tail.is_empty() {
+            return format!("http://{}", host);
+        } else {
+            return format!("http://{}/{}", host, tail);
+        }
+    }
+
+    let is_tilde = s.starts_with("~/");
+    let rest = s.strip_prefix("~/").or_else(|| s.strip_prefix("/")).unwrap_or(s);
+
+    let tail = rest
+        .split('/')
+        .filter_map(|seg| {
+            let t = seg.trim();
+            if t.is_empty() {
+                None
+            } else {
+                Some(t.to_lowercase())
+            }
+        })
+        .collect::<Vec<_>>()
+        .join("/");
+
+    if is_tilde {
+        format!("https://slug.social/~/{}", tail)
+    } else if tail.is_empty() {
+        "https://slug.social".to_string()
+    } else {
+        format!("https://slug.social/{}", tail)
+    }
+}
+
+pub fn item_path_segments(input: &str) -> Vec<String> {
+    let canonical = canonicalize_item(input);
+    if canonical.is_empty() {
+        return vec![];
+    }
+
+    if let Some(rest) = canonical.strip_prefix("https://") {
+        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
+        let mut out = vec![format!("https://{}", host)];
+        out.extend(tail.split('/').filter(|s| !s.is_empty()).map(|s| s.to_string()));
+        return out;
+    }
+    if let Some(rest) = canonical.strip_prefix("http://") {
+        let (host, tail) = rest.split_once('/').map_or((rest, ""), |(h, t)| (h, t));
+        let mut out = vec![format!("http://{}", host)];
+        out.extend(tail.split('/').filter(|s| !s.is_empty()).map(|s| s.to_string()));
+        return out;
+    }
+
+    canonical
+        .split('/')
+        .filter(|s| !s.is_empty())
+        .map(|s| s.to_string())
+        .collect()
+}
+
+pub fn item_parent_path(input: &str) -> Option<String> {
+    let segs = item_path_segments(input);
+    if segs.len() <= 1 {
+        return None;
+    }
+    Some(segs[..segs.len() - 1].join("/"))
+}
+
+// ---------------------------------------------------------------------------
+// Storage + input path newtypes
+// ---------------------------------------------------------------------------
+
+/// Canonical item identifier as produced by [`canonicalize_item`].
+///
+/// Shared across all scopes; room is not embedded. Usually
+/// `https://slug.social/~/…` or an external `http(s)://…` URL item.
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
+pub struct CanonicalItemUrl(pub String);
+
+impl CanonicalItemUrl {
+    pub fn parse(input: &str) -> Option<Self> {
+        let c = canonicalize_item(input);
+        if c.is_empty() {
+            None
+        } else {
+            Some(Self(c))
+        }
+    }
+
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+
+    pub fn tilde_tail(&self) -> Option<&str> {
+        self.0.strip_prefix("https://slug.social/~/")
+    }
+
+    pub fn last_segment(&self) -> &str {
+        self.0
+            .rsplit('/')
+            .find(|s| !s.is_empty())
+            .unwrap_or(self.0.as_str())
+    }
+
+    pub fn ontology_root() -> Self {
+        Self("https://slug.social/~".to_string())
+    }
+
+    pub fn parent(&self) -> Option<Self> {
+        if self.tilde_tail().map(|t| t.is_empty()).unwrap_or(true) {
+            return None;
+        }
+        let last_slash = self.0.rfind('/')?;
+        let parent_str = &self.0[..last_slash];
+        if parent_str.is_empty() {
+            None
+        } else {
+            Some(Self(parent_str.to_string()))
+        }
+    }
+
+    pub fn tilde_segments(&self) -> Vec<&str> {
+        match self.tilde_tail() {
+            Some(tail) if !tail.is_empty() => {
+                std::iter::once("~")
+                    .chain(tail.split('/').filter(|s| !s.is_empty()))
+                    .collect()
+            }
+            Some(_) => vec!["~"],
+            None => vec![],
+        }
+    }
+
+    /// `~/…` list label for ontology items (paths index, CLI).
+    pub fn tilde_list_label(&self) -> TildeOntologyPath {
+        TildeOntologyPath::from_stored(self)
+    }
+
+    /// Absolute href for JSON/RPC and browsers for this stored id in `room`.
+    pub fn json_href(&self, room_wire: &str) -> GardenItemUrl {
+        GardenItemUrl::from_stored(self, room_wire)
+    }
+}
+
+impl fmt::Display for CanonicalItemUrl {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+impl Borrow<str> for CanonicalItemUrl {
+    fn borrow(&self) -> &str {
+        &self.0
+    }
+}
+
+impl PartialEq<str> for CanonicalItemUrl {
+    fn eq(&self, other: &str) -> bool {
+        self.0 == other
+    }
+}
+
+impl PartialEq<&str> for CanonicalItemUrl {
+    fn eq(&self, other: &&str) -> bool {
+        self.0 == *other
+    }
+}
+
+impl PartialEq<String> for CanonicalItemUrl {
+    fn eq(&self, other: &String) -> bool {
+        &self.0 == other
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
+pub struct TildePath(pub String);
+
+impl TildePath {
+    pub fn new(input: &str) -> Option<Self> {
+        let s = input.trim();
+        if s.starts_with("~/") && s.len() > 2 {
+            Some(Self(s.to_string()))
+        } else if s == "~/" {
+            Some(Self("~/".to_string()))
+        } else {
+            None
+        }
+    }
+
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+
+    pub fn canonicalize(&self) -> Option<CanonicalItemUrl> {
+        CanonicalItemUrl::parse(&self.0)
+    }
+}
+
+impl fmt::Display for TildePath {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
+pub struct RelativePath(pub String);
+
+impl RelativePath {
+    pub fn new(input: &str) -> Option<Self> {
+        let s = input.trim().trim_matches('/');
+        if s.is_empty() {
+            Some(Self(String::new()))
+        } else {
+            Some(Self(s.to_string()))
+        }
+    }
+
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+
+    pub fn join_under_ontology_root(&self, root: &CanonicalItemUrl) -> Option<CanonicalItemUrl> {
+        let base = root.tilde_tail()?;
+        let joined = if base.is_empty() {
+            if self.0.is_empty() {
+                "~/".to_string()
+            } else {
+                format!("~/{}", self.0)
+            }
+        } else if self.0.is_empty() {
+            format!("~/{}", base)
+        } else {
+            format!("~/{}/{}", base.trim_end_matches('/'), self.0)
+        };
+        CanonicalItemUrl::parse(&joined)
+    }
+}
+
+impl fmt::Display for RelativePath {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+// ---------------------------------------------------------------------------
+// Wire / JSON: correct-by-construction hrefs
+// ---------------------------------------------------------------------------
+
+fn api_path_or_url(item: &str) -> String {
+    if item.starts_with("http://") || item.starts_with("https://") {
+        item.to_string()
+    } else {
+        format!("/{}", item)
+    }
+}
+
+/// Ontology item as serialized in JSON (absolute URL or `/`-prefixed path).
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
+#[serde(transparent)]
+pub struct GardenItemUrl(pub String);
+
+impl GardenItemUrl {
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+
+    pub fn into_inner(self) -> String {
+        self.0
+    }
+
+    /// Stored canonical id + RPC `room` field (`"public"` or `"short/slug"`).
+    pub fn from_stored(stored: &CanonicalItemUrl, room_wire: &str) -> Self {
+        Self(garden_href_string(stored.as_str(), room_wire))
+    }
+
+    /// Like [`Self::from_stored`] but accepts a string that may already be canonical.
+    pub fn from_storage_str(stored: &str, room_wire: &str) -> Self {
+        Self(garden_href_string(stored, room_wire))
+    }
+}
+
+impl fmt::Display for GardenItemUrl {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+fn garden_href_string(item: &str, room_wire: &str) -> String {
+    let room = room_wire.trim();
+    if room.is_empty() || room == "public" {
+        return api_path_or_url(item);
+    }
+    let Some((short, slug)) = room.split_once('/') else {
+        return api_path_or_url(item);
+    };
+    if short.is_empty() || slug.is_empty() {
+        return api_path_or_url(item);
+    }
+    let Some(c) = CanonicalItemUrl::parse(item) else {
+        return api_path_or_url(item);
+    };
+    let root = CanonicalItemUrl::ontology_root();
+    let item_norm = c.as_str().trim_end_matches('/');
+    let root_norm = root.as_str().trim_end_matches('/');
+    if let Some(tail) = c.tilde_tail() {
+        return if tail.is_empty() {
+            format!("https://slug.social/r/{short}/{slug}/~")
+        } else {
+            format!("https://slug.social/r/{short}/{slug}/~/{}", tail)
+        };
+    }
+    if item_norm == root_norm {
+        return format!("https://slug.social/r/{short}/{slug}/~");
+    }
+    api_path_or_url(item)
+}
+
+/// Forum thread URL for JSON (`/t/…` or `/r/…/t/…` on slug.social).
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
+#[serde(transparent)]
+pub struct ForumThreadUrl(pub String);
+
+impl ForumThreadUrl {
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+
+    pub fn into_inner(self) -> String {
+        self.0
+    }
+
+    pub fn from_room_tag(room_wire: &str, thread_tag: &str) -> Self {
+        let room = room_wire.trim();
+        let tag = thread_tag.trim().trim_start_matches('#');
+        Self(if room.is_empty() || room == "public" {
+            format!("https://slug.social/t/{tag}")
+        } else if let Some((short, slug)) = room.split_once('/') {
+            if short.is_empty() || slug.is_empty() {
+                format!("https://slug.social/t/{tag}")
+            } else {
+                format!("https://slug.social/r/{short}/{slug}/t/{tag}")
+            }
+        } else {
+            format!("https://slug.social/t/{tag}")
+        })
+    }
+}
+
+impl fmt::Display for ForumThreadUrl {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+/// `~/a/b` style path for list UIs (paths index `path` field).
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+#[serde(transparent)]
+pub struct TildeOntologyPath(pub String);
+
+impl TildeOntologyPath {
+    pub fn from_stored(c: &CanonicalItemUrl) -> Self {
+        let s = match c.tilde_tail() {
+            Some(tail) if !tail.is_empty() => format!("~/{}", tail),
+            Some(_) => "~/".to_string(),
+            None => c.to_string(),
+        };
+        Self(s)
+    }
+
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+}
+
+impl fmt::Display for TildeOntologyPath {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn canonical_parent_deep() {
+        let c = CanonicalItemUrl::parse("~/a/b/c").unwrap();
+        assert_eq!(c.parent().unwrap().as_str(), "https://slug.social/~/a/b");
+    }
+
+    #[test]
+    fn canonical_parent_one_level() {
+        let c = CanonicalItemUrl::parse("~/a").unwrap();
+        assert_eq!(c.parent().unwrap().as_str(), "https://slug.social/~");
+    }
+
+    #[test]
+    fn canonical_parent_root_is_none() {
+        let root = CanonicalItemUrl::parse("~/").unwrap();
+        assert!(root.parent().is_none());
+    }
+
+    #[test]
+    fn tilde_segments_deep() {
+        let c = CanonicalItemUrl::parse("~/a/b").unwrap();
+        assert_eq!(c.tilde_segments(), vec!["~", "a", "b"]);
+    }
+
+    #[test]
+    fn tilde_segments_root() {
+        let c = CanonicalItemUrl::parse("~/").unwrap();
+        assert_eq!(c.tilde_segments(), vec!["~"]);
+    }
+
+    #[test]
+    fn tilde_segments_non_ontology_is_empty() {
+        let c = CanonicalItemUrl::parse("https://example.com/foo").unwrap();
+        assert_eq!(c.tilde_segments(), Vec::<&str>::new());
+    }
+
+    #[test]
+    fn garden_public_passthrough_https() {
+        let u = "https://slug.social/~/a/b";
+        assert_eq!(GardenItemUrl::from_storage_str(u, "public").as_str(), u);
+    }
+
+    #[test]
+    fn garden_private_room_prefixes_ontology() {
+        assert_eq!(
+            GardenItemUrl::from_storage_str("https://slug.social/~/topic/x", "9ab12cd/my-room").as_str(),
+            "https://slug.social/r/9ab12cd/my-room/~/topic/x"
+        );
+    }
+
+    #[test]
+    fn garden_private_room_ontology_root() {
+        assert_eq!(
+            GardenItemUrl::from_storage_str("https://slug.social/~", "9ab12cd/my-room").as_str(),
+            "https://slug.social/r/9ab12cd/my-room/~"
+        );
+        assert_eq!(
+            GardenItemUrl::from_storage_str("https://slug.social/~/", "9ab12cd/my-room").as_str(),
+            "https://slug.social/r/9ab12cd/my-room/~"
+        );
+    }
+
+    #[test]
+    fn garden_external_url_untouched_in_private_room() {
+        let u = "https://example.com/z";
+        assert_eq!(GardenItemUrl::from_storage_str(u, "9ab12cd/my-room").as_str(), u);
+    }
+
+    #[test]
+    fn forum_web_public_vs_room() {
+        assert_eq!(
+            ForumThreadUrl::from_room_tag("public", "debate").as_str(),
+            "https://slug.social/t/debate"
+        );
+        assert_eq!(
+            ForumThreadUrl::from_room_tag("9ab12cd/my-room", "#debate").as_str(),
+            "https://slug.social/r/9ab12cd/my-room/t/debate"
+        );
+    }
+}