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:
[8d8230d1] reddit

Side A — unified diff (full patch):
diff --git a/.gitignore b/.gitignore
index 4c7073f9fac0c30fd2050d79a60ef447af58ebeb..ada462e900d24a3a6d08165d158c80f79c35a5a5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@
 data/
 repomix-output.xml
 dev-data/
+.env
diff --git a/server/Cargo.toml b/server/Cargo.toml
index 7906a8547d56b8e6a48ef59c37aa82a8510fdee9..4677fedcb45292eebebe7e9cf6ce2f5738f18ddf 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -16,6 +16,7 @@ tower = "0.5"
 tower-http = { version = "0.5", features = ["trace"] }
 tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
+reqwest = { version = "0.12", features = ["json"] }
 
 [dev-dependencies]
 reqwest = { version = "0.12", features = ["json"] }
diff --git a/server/src/html/mod.rs b/server/src/html/mod.rs
index 2864407ed6e8ec284a1dc663acf1805534566b62..df6505021d9f446c2b453e20e3eb3cf696a111f9 100644
--- a/server/src/html/mod.rs
+++ b/server/src/html/mod.rs
@@ -272,5 +272,16 @@ pub async fn home(State(state): State<AppState>, uri: Uri) -> impl IntoResponse
 
 pub async fn browse(State(state): State<AppState>, uri: Uri) -> impl IntoResponse {
     let item = ItemId::from_browse_uri(uri.path()).unwrap_or(ItemId::root());
+    if item.as_str().starts_with("reddit.com") {
+        let needs_fetch = {
+            let tree = state.tree.read().await;
+            tree.get(&item)
+                .map(|n| n.data.is_none())
+                .unwrap_or(true)
+        };
+        if needs_fetch {
+            state.reddit.request_fetch(item.clone());
+        }
+    }
     item_page(state, uri, item).await
 }
diff --git a/server/src/reddit.rs b/server/src/reddit.rs
index d203dca09245daf869b3aa942898447700ae69fb..90053ad03b1d7c8e94f325dd4ee64c2b4f7da900 100644
--- a/server/src/reddit.rs
+++ b/server/src/reddit.rs
@@ -1,4 +1,12 @@
-//! Reddit API import (async, decoupled from UI request path).
+//! Reddit API import via a single background worker (rate limits, dedup, backoff).
+
+use std::collections::{HashMap, HashSet};
+use std::sync::Arc;
+use std::time::{Duration, Instant};
+
+use reqwest::{header, Client, StatusCode};
+use serde::Deserialize;
+use tokio::sync::{mpsc, RwLock};
 
 use crate::{
     path_types::ItemId,
@@ -10,12 +18,401 @@ pub fn ensure_partial_tree(tree: &mut GlobalTree, id: &ItemId) {
     tree.ensure_path(id);
 }
 
-/// Placeholder for Reddit JSON import. Returns entity data when implemented.
-pub async fn fetch_reddit_entity(_id: &ItemId) -> Option<EntityData> {
-    None
+pub struct RedditCommand {
+    pub id: ItemId,
+}
+
+#[derive(Clone)]
+pub struct RedditBroker {
+    tx: mpsc::Sender<RedditCommand>,
+}
+
+#[derive(Clone)]
+struct RedditCredentials {
+    client_id: String,
+    client_secret: String,
+}
+
+struct OAuthToken {
+    access_token: String,
+    expires_at: Instant,
+}
+
+impl RedditBroker {
+    pub fn spawn(tree: Arc<RwLock<GlobalTree>>, user_agent: &str) -> Self {
+        let (tx, rx) = mpsc::channel(100);
+
+        let mut headers = header::HeaderMap::new();
+        headers.insert(
+            header::USER_AGENT,
+            header::HeaderValue::from_str(user_agent).expect("valid user agent"),
+        );
+
+        let client = Client::builder()
+            .default_headers(headers)
+            .timeout(Duration::from_secs(15))
+            .build()
+            .expect("reqwest client");
+
+        let creds = RedditCredentials::from_env();
+        tokio::spawn(reddit_worker(rx, tree, client, creds));
+
+        Self { tx }
+    }
+
+    /// Fire-and-forget: queue a fetch; worker updates the tree when done.
+    pub fn request_fetch(&self, id: ItemId) {
+        let _ = self.tx.try_send(RedditCommand { id });
+    }
+}
+
+impl RedditCredentials {
+    fn from_env() -> Option<Self> {
+        let client_id = std::env::var("REDDIT_CLIENT_ID").ok()?;
+        let client_secret = std::env::var("REDDIT_CLIENT_SECRET").ok()?;
+        if client_id.is_empty() || client_secret.is_empty() {
+            return None;
+        }
+        Some(Self {
+            client_id,
+            client_secret,
+        })
+    }
+}
+
+pub fn default_user_agent() -> String {
+    std::env::var("REDDIT_USER_AGENT").unwrap_or_else(|_| {
+        "web:sorter2.social:v0.0.1 (by /u/sorter2)".to_string()
+    })
 }
 
-/// Apply fetched entity data to a node (called from async worker).
-pub fn apply_entity(tree: &mut GlobalTree, id: &ItemId, data: EntityData) {
-    tree.set_entity_data(id, data);
+async fn reddit_worker(
+    mut rx: mpsc::Receiver<RedditCommand>,
+    tree: Arc<RwLock<GlobalTree>>,
+    client: Client,
+    creds: Option<RedditCredentials>,
+) {
+    let mut in_flight = HashSet::new();
+    let mut recently_fetched: HashMap<ItemId, Instant> = HashMap::new();
+    let mut current_delay = Duration::from_secs(1);
+    let mut oauth: Option<OAuthToken> = None;
+    let cache_ttl = Duration::from_secs(300);
+
+    while let Some(cmd) = rx.recv().await {
+        let now = Instant::now();
+        recently_fetched.retain(|_, t| now.duration_since(*t) < cache_ttl);
+
+        if in_flight.contains(&cmd.id) || recently_fetched.contains_key(&cmd.id) {
+            continue;
+        }
+
+        in_flight.insert(cmd.id.clone());
+        let fetch_id = cmd.id.clone();
+
+        tokio::time::sleep(current_delay).await;
+
+        if let Some(c) = &creds {
+            oauth = ensure_oauth_token(&client, c, oauth.take()).await;
+        }
+
+        let token = oauth.as_ref().map(|t| t.access_token.as_str());
+        let use_oauth = token.is_some();
+
+        match do_fetch(&client, &fetch_id, use_oauth, token).await {
+            Ok(FetchOutcome::Entity(data)) => {
+                let mut w = tree.write().await;
+                w.set_entity_data(&fetch_id, data);
+                recently_fetched.insert(fetch_id.clone(), Instant::now());
+                current_delay = Duration::from_millis(600);
+            }
+            Ok(FetchOutcome::NotFound) => {
+                recently_fetched.insert(fetch_id.clone(), Instant::now());
+            }
+            Ok(FetchOutcome::RateLimited { reset_secs }) => {
+                let wait = Duration::from_secs(reset_secs.max(1));
+                tracing::warn!(
+                    "Reddit rate limit for {}; sleeping {}s",
+                    fetch_id,
+                    wait.as_secs()
+                );
+                tokio::time::sleep(wait).await;
+                current_delay = (current_delay * 2).min(Duration::from_secs(60));
+            }
+            Err(e) => {
+                tracing::warn!("Reddit fetch failed for {}: {}", fetch_id, e);
+                current_delay = (current_delay * 2).min(Duration::from_secs(60));
+            }
+        }
+
+        in_flight.remove(&fetch_id);
+    }
+}
+
+enum FetchOutcome {
+    Entity(EntityData),
+    NotFound,
+    RateLimited { reset_secs: u64 },
+}
+
+async fn ensure_oauth_token(
+    client: &Client,
+    creds: &RedditCredentials,
+    existing: Option<OAuthToken>,
+) -> Option<OAuthToken> {
+    if let Some(t) = existing {
+        if Instant::now() < t.expires_at - Duration::from_secs(60) {
+            return Some(t);
+        }
+    }
+
+    let resp = client
+        .post("https://www.reddit.com/api/v1/access_token")
+        .basic_auth(&creds.client_id, Some(&creds.client_secret))
+        .form(&[("grant_type", "client_credentials")])
+        .send()
+        .await;
+
+    let resp = match resp {
+        Ok(r) => r,
+        Err(e) => {
+            tracing::warn!("Reddit OAuth token request failed: {e}");
+            return None;
+        }
+    };
+
+    if !resp.status().is_success() {
+        tracing::warn!("Reddit OAuth token HTTP {}", resp.status());
+        return None;
+    }
+
+    #[derive(Deserialize)]
+    struct TokenResponse {
+        access_token: String,
+        expires_in: u64,
+    }
+
+    let body: TokenResponse = match resp.json().await {
+        Ok(b) => b,
+        Err(e) => {
+            tracing::warn!("Reddit OAuth token parse failed: {e}");
+            return None;
+        }
+    };
+
+    Some(OAuthToken {
+        access_token: body.access_token,
+        expires_at: Instant::now() + Duration::from_secs(body.expires_in),
+    })
+}
+
+async fn do_fetch(
+    client: &Client,
+    id: &ItemId,
+    use_oauth: bool,
+    bearer: Option<&str>,
+) -> Result<FetchOutcome, String> {
+    let url = map_item_to_reddit_api(id, use_oauth);
+    if url.is_empty() {
+        return Ok(FetchOutcome::NotFound);
+    }
+
+    let mut req = client.get(&url);
+    if let Some(token) = bearer {
+        req = req.bearer_auth(token);
+    }
+
+    let resp = req.send().await.map_err(|e| e.to_string())?;
+
+    if resp.status() == StatusCode::TOO_MANY_REQUESTS {
+        let reset = rate_limit_reset_secs(&resp);
+        return Ok(FetchOutcome::RateLimited { reset_secs: reset });
+    }
+
+    if resp.status() == StatusCode::SERVICE_UNAVAILABLE {
+        return Err("Reddit unavailable (503)".to_string());
+    }
+
+    if !resp.status().is_success() {
+        return Ok(FetchOutcome::NotFound);
+    }
+
+    if rate_limit_remaining(&resp) == Some(0) {
+        let reset = rate_limit_reset_secs(&resp);
+        return Ok(FetchOutcome::RateLimited { reset_secs: reset });
+    }
+
+    let bytes = resp.bytes().await.map_err(|e| e.to_string())?;
+    Ok(parse_reddit_json(id, &bytes)
+        .map(FetchOutcome::Entity)
+        .unwrap_or(FetchOutcome::NotFound))
+}
+
+fn rate_limit_remaining(resp: &reqwest::Response) -> Option<u64> {
+    resp.headers()
+        .get("x-ratelimit-remaining")
+        .and_then(|v| v.to_str().ok())
+        .and_then(|s| s.parse::<f64>().ok())
+        .map(|f| f.floor() as u64)
+}
+
+fn rate_limit_reset_secs(resp: &reqwest::Response) -> u64 {
+    resp.headers()
+        .get("x-ratelimit-reset")
+        .and_then(|v| v.to_str().ok())
+        .and_then(|s| s.parse::<f64>().ok())
+        .map(|f| f.ceil() as u64)
+        .unwrap_or(5)
+}
+
+/// Map canonical item id to Reddit JSON API URL.
+pub fn map_item_to_reddit_api(id: &ItemId, oauth: bool) -> String {
+    let path = id.as_str();
+    if !path.starts_with("reddit.com/") && path != "reddit.com" {
+        return String::new();
+    }
+
+    let base = if oauth {
+        "https://oauth.reddit.com"
+    } else {
+        "https://www.reddit.com"
+    };
+
+    let segments: Vec<&str> = path.split('/').collect();
+
+    if let Some(i) = segments.iter().position(|&p| p == "comments") {
+        if segments.len() > i + 1 {
+            let api_path = segments[1..=i + 1].join("/");
+            return format!("{base}/{api_path}.json?raw_json=1");
+        }
+    }
+
+    if segments.len() == 3 && segments[1] == "r" {
+        return format!("{base}/r/{}/about.json?raw_json=1", segments[2]);
+    }
+
+    String::new()
+}
+
+fn parse_reddit_json(id: &ItemId, bytes: &[u8]) -> Option<EntityData> {
+    let v: serde_json::Value = serde_json::from_slice(bytes).ok()?;
+    let segments: Vec<&str> = id.as_str().split('/').collect();
+
+    if segments.iter().any(|&p| p == "comments") {
+        parse_post_listing(&v)
+    } else {
+        parse_subreddit_about(&v)
+    }
+}
+
+fn parse_subreddit_about(v: &serde_json::Value) -> Option<EntityData> {
+    let data = v.get("data")?;
+    let title = data
+        .get("title")
+        .or_else(|| data.get("display_name"))
+        .and_then(|t| t.as_str())?
+        .to_string();
+    let body_html = data
+        .get("public_description_html")
+        .or_else(|| data.get("public_description"))
+        .and_then(|t| t.as_str())
+        .map(|s| s.to_string());
+    let thumb_url = data
+        .get("icon_img")
+        .or_else(|| data.get("community_icon"))
+        .and_then(|t| t.as_str())
+        .filter(|s| !s.is_empty())
+        .map(|s| s.to_string());
+
+    Some(EntityData {
+        title,
+        author: None,
+        body_html,
+        thumb_url,
+    })
+}
+
+fn parse_post_listing(v: &serde_json::Value) -> Option<EntityData> {
+    let listing = v.as_array()?.first()?;
+    let child = listing
+        .pointer("/data/children/0/data")?;
+    let title = child.get("title")?.as_str()?.to_string();
+    let author = child
+        .get("author")
+        .and_then(|a| a.as_str())
+        .filter(|a| *a != "[deleted]")
+        .map(|s| s.to_string());
+    let body_html = child
+        .get("selftext_html")
+        .and_then(|t| t.as_str())
+        .filter(|s| !s.is_empty())
+        .map(|s| s.to_string());
+    let thumb_url = child
+        .get("thumbnail")
+        .and_then(|t| t.as_str())
+        .filter(|s| s.starts_with("http"))
+        .map(|s| s.to_string());
+
+    Some(EntityData {
+        title,
+        author,
+        body_html,
+        thumb_url,
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn map_subreddit_about_url() {
+        let id = ItemId::parse("reddit.com/r/rust").unwrap();
+        assert_eq!(
+            map_item_to_reddit_api(&id, false),
+            "https://www.reddit.com/r/rust/about.json?raw_json=1"
+        );
+        assert_eq!(
+            map_item_to_reddit_api(&id, true),
+            "https://oauth.reddit.com/r/rust/about.json?raw_json=1"
+        );
+    }
+
+    #[test]
+    fn map_post_url() {
+        let id =
+            ItemId::parse("reddit.com/r/amitheasshole/comments/1trnvdl").unwrap();
+        assert_eq!(
+            map_item_to_reddit_api(&id, false),
+            "https://www.reddit.com/r/amitheasshole/comments/1trnvdl.json?raw_json=1"
+        );
+    }
+
+    #[test]
+    fn map_non_reddit_empty() {
+        let id = ItemId::opaque("example.com/foo");
+        assert!(map_item_to_reddit_api(&id, false).is_empty());
+    }
+
+    #[test]
+    fn parse_subreddit_fixture() {
+        let json = r#"{"kind":"t5","data":{"title":"Rust","display_name":"rust","public_description":"systems"}}"#;
+        let entity = parse_reddit_json(
+            &ItemId::parse("reddit.com/r/rust").unwrap(),
+            json.as_bytes(),
+        )
+        .unwrap();
+        assert_eq!(entity.title, "Rust");
+    }
+
+    #[test]
+    fn parse_post_fixture() {
+        let json = r#"[{"kind":"Listing","data":{"children":[{"kind":"t3","data":{"title":"AITA","author":"op","selftext_html":"&lt;p&gt;hi&lt;/p&gt;","thumbnail":"https://b.thumbs.redditmedia.com/x.jpg"}}]}}]"#;
+        let entity = parse_reddit_json(
+            &ItemId::parse("reddit.com/r/x/comments/abc").unwrap(),
+            json.as_bytes(),
+        )
+        .unwrap();
+        assert_eq!(entity.title, "AITA");
+        assert_eq!(entity.author.as_deref(), Some("op"));
+    }
 }
diff --git a/server/src/state.rs b/server/src/state.rs
index cc1722f5a5bf4d415f2327ea585c488a15a75592..8c03aa60c15aee803a534439400b69935b1a3d84 100644
--- a/server/src/state.rs
+++ b/server/src/state.rs
@@ -5,9 +5,10 @@ use tokio::sync::RwLock;
 use crate::{
     event_log::EventLog,
     events::Event,
+    journal::JournalClient,
     path_types::ItemId,
+    reddit::{default_user_agent, RedditBroker},
     reducer::{GlobalTree, VoteData},
-    journal::JournalClient,
     views::ViewStore,
 };
 
@@ -73,6 +74,7 @@ pub struct AppState {
     pub views: ViewStore,
     pub tree: Arc<RwLock<GlobalTree>>,
     journal: JournalClient,
+    pub reddit: RedditBroker,
 }
 
 impl AppState {
@@ -112,6 +114,7 @@ impl AppState {
 
         let tree = Arc::new(RwLock::new(tree));
         let journal = JournalClient::spawn(tree.clone(), event_log.clone());
+        let reddit = RedditBroker::spawn(tree.clone(), &default_user_agent());
 
         Self {
             cfg: Arc::new(cfg),
@@ -119,6 +122,7 @@ impl AppState {
             views,
             tree,
             journal,
+            reddit,
         }
     }
 
@@ -127,8 +131,11 @@ impl AppState {
             id: id.as_str().to_string(),
         };
         self.event_log.append(&event).await.map_err(|e| e.to_string())?;
-        let mut w = self.tree.write().await;
-        w.ensure_path(id);
+        {
+            let mut w = self.tree.write().await;
+            w.ensure_path(id);
+        }
+        self.reddit.request_fetch(id.clone());
         Ok(())
     }
 
diff --git a/todo b/todo
new file mode 100644
index 0000000000000000000000000000000000000000..d196e8cb4cc80ccb95eeff01c73607d520e13212
--- /dev/null
+++ b/todo
@@ -0,0 +1,7 @@
+reddit import (only on explicit request)
+reddit rendering
+vote redering
+pair chosing
+nsfw gate
+
+logins (uuid user, two sides, oauths, and pseudonyms)


Side B — contributor: tommy-mor
Side B — 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 B — 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,
     },