diff --git a/hive-c0re/src/dashboard.rs b/hive-c0re/src/dashboard.rs
index 187c93a4..c6814952 100644
--- a/hive-c0re/src/dashboard.rs
+++ b/hive-c0re/src/dashboard.rs
@@ -33,6 +33,7 @@ mod approvals;
 mod build_logs;
 mod journal;
 mod lifecycle_ops;
+mod matrix_accounts;
 pub(crate) mod permissions;
 mod questions;
 mod reminders;
@@ -100,6 +101,10 @@ pub async fn serve(port: u16, coord: Arc<Coordinator>) -> Result<()> {
         .route("/api/journal-host", get(journal::get_journal_host))
         .route("/api/approval-diff/{id}", get(approvals::get_approval_diff))
         .route("/api/state-file", get(state_files::get_state_file))
+        .route(
+            "/api/matrix-accounts",
+            get(matrix_accounts::get_matrix_accounts),
+        )
         .route("/api/reminders", get(reminders::api_reminders))
         .route("/api/operator-inbox", get(api_operator_inbox))
         .route("/api/stats-hive", get(api_stats_hive))
diff --git a/hive-c0re/src/dashboard/matrix_accounts.rs b/hive-c0re/src/dashboard/matrix_accounts.rs
new file mode 100644
index 00000000..8d2d01bd
--- /dev/null
+++ b/hive-c0re/src/dashboard/matrix_accounts.rs
@@ -0,0 +1,128 @@
+//! Matrix-account listing for the dashboard (#1698 backend, BE-1).
+//!
+//! `GET /api/matrix-accounts?agent=<name>` returns the matrix accounts an
+//! agent currently has a token provisioned for. v1 derives the list cheaply
+//! from the agent's state dir — every `matrix-token*` file is a provisioned
+//! account (`matrix-token` = the hive-internal `main` account;
+//! `matrix-token-<name>` = an extra account, matching the daemon's
+//! path-watcher glob). It does not read the nix config, so it lists what is
+//! *provisioned*, not the full configured set: a config-declared account
+//! without a token yet appears once it is provisioned via the login form.
+//! Homeserver + live up/down status arrive in v2 from the daemon's account
+//! registry; here `homeserver` is always `null`.
+
+use axum::extract::Query;
+use axum::response::{IntoResponse, Response};
+use serde::{Deserialize, Serialize};
+
+use super::error_response;
+use crate::coordinator::Coordinator;
+
+#[derive(Deserialize)]
+pub(super) struct MatrixAccountsQuery {
+    agent: String,
+}
+
+#[derive(Serialize)]
+struct MatrixAccount {
+    name: String,
+    /// Always `None` in v1 (derived from the token filename, which carries no
+    /// homeserver); populated in v2 from the daemon's account registry.
+    homeserver: Option<String>,
+    token_present: bool,
+}
+
+#[derive(Serialize)]
+struct MatrixAccountsResponse {
+    accounts: Vec<MatrixAccount>,
+}
+
+/// Map a state-dir filename to the matrix account name it provisions, or
+/// `None` if it is not a token file. `matrix-token` → the hive-internal
+/// `main` account; `matrix-token-<name>` → the extra account `<name>`.
+fn account_name_from_filename(fname: &str) -> Option<String> {
+    if fname == "matrix-token" {
+        return Some("main".to_owned());
+    }
+    let suffix = fname.strip_prefix("matrix-token-")?;
+    if suffix.is_empty() {
+        return None;
+    }
+    Some(suffix.to_owned())
+}
+
+pub(super) async fn get_matrix_accounts(Query(q): Query<MatrixAccountsQuery>) -> Response {
+    let agent = q.agent.trim();
+    // Agent names are simple identifiers; reject anything else so a crafted
+    // `agent` can't escape the per-agent state root via path components.
+    if agent.is_empty()
+        || !agent
+            .chars()
+            .all(|c| c.is_ascii_alphanumeric() || c == '-' || c == '_')
+    {
+        return error_response(&format!("matrix-accounts: invalid agent name {agent:?}"));
+    }
+
+    let dir = Coordinator::agent_notes_dir(agent);
+    let mut accounts = Vec::new();
+    match std::fs::read_dir(&dir) {
+        Ok(entries) => {
+            for entry in entries.flatten() {
+                if !entry.file_type().is_ok_and(|ft| ft.is_file()) {
+                    continue;
+                }
+                let fname = entry.file_name();
+                let Some(fname) = fname.to_str() else {
+                    continue;
+                };
+                if let Some(name) = account_name_from_filename(fname) {
+                    accounts.push(MatrixAccount {
+                        name,
+                        homeserver: None,
+                        token_present: true,
+                    });
+                }
+            }
+        }
+        // No state dir / no tokens yet is a normal empty result, not an error.
+        Err(e) if e.kind() == std::io::ErrorKind::NotFound => {}
+        Err(e) => {
+            return error_response(&format!("matrix-accounts: read {}: {e}", dir.display()));
+        }
+    }
+    accounts.sort_by(|a, b| a.name.cmp(&b.name));
+    axum::Json(MatrixAccountsResponse { accounts }).into_response()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::account_name_from_filename;
+
+    #[test]
+    fn main_account_from_bare_token() {
+        assert_eq!(
+            account_name_from_filename("matrix-token").as_deref(),
+            Some("main")
+        );
+    }
+
+    #[test]
+    fn extra_account_from_suffixed_token() {
+        assert_eq!(
+            account_name_from_filename("matrix-token-catgirl").as_deref(),
+            Some("catgirl")
+        );
+    }
+
+    #[test]
+    fn empty_suffix_is_not_an_account() {
+        assert_eq!(account_name_from_filename("matrix-token-"), None);
+    }
+
+    #[test]
+    fn non_token_files_ignored() {
+        assert_eq!(account_name_from_filename("matrix-sdk-state"), None);
+        assert_eq!(account_name_from_filename("notes.md"), None);
+        assert_eq!(account_name_from_filename("matrix-avatar-icon-hash"), None);
+    }
+}