diff --git a/flake.nix b/flake.nix
index 8eef657c..63818b00 100644
--- a/flake.nix
+++ b/flake.nix
@@ -149,34 +149,20 @@
 
       nixosConfigurations =
         let
-          # Values the agent modules require but that only a real
-          # deployment can know. Real containers are built from the
-          # generated meta flake, where hive-c0re renders these per
-          # agent from the host's `HIVE_FORGE_URL` (see meta.rs's
-          # `SERVICE_URL_OPTIONS`) — they never evaluate through
-          # `self.nixosConfigurations`, so nothing here can reach a
-          # running agent. These two configs exist only to typecheck
-          # the modules and to pre-build the container closure
-          # (`system.extraDependencies`, see hive-c0re/default.nix).
-          #
-          # Deliberately a `.invalid` host (RFC 2606: guaranteed not to
-          # resolve) rather than something plausible like a loopback
-          # port. If this value ever *did* escape into a runtime path,
-          # it must fail loudly at DNS instead of quietly connecting to
-          # whatever happens to be listening — which is the entire
-          # point of removing the `http://localhost:3000` default this
-          # replaces.
-          evalOnlyPlaceholders = {
-            hyperhive.forge.url = "http://forge.invalid";
-          };
+          # These two configs are what hive-c0re extends per agent
+          # (meta.rs's `mkAgent` does `<base>.extendModules { … }`, so
+          # the built base and every container stay on one version).
+          # Nothing deployment-specific may be set here: it would be
+          # inherited by every container on the hive and collide with
+          # the per-agent values hive-c0re renders. The agent modules
+          # are written so a bare evaluation needs no such values —
+          # service URLs default to `null`, meaning "not configured",
+          # and the units that would use them simply aren't generated.
           mkContainer =
             module:
             nixpkgs.lib.nixosSystem {
               system = "x86_64-linux";
-              modules = [
-                module
-                evalOnlyPlaceholders
-              ];
+              modules = [ module ];
             };
         in
         {
diff --git a/hive-c0re/src/dashboard/build_logs.rs b/hive-c0re/src/dashboard/build_logs.rs
index 990af3ef..7c741a52 100644
--- a/hive-c0re/src/dashboard/build_logs.rs
+++ b/hive-c0re/src/dashboard/build_logs.rs
@@ -207,6 +207,18 @@ struct BuildLogFrame {
 /// always carries the full accumulated log so far (cursors start at 0);
 /// subsequent frames carry only new bytes. `done: true` on the final
 /// frame signals the browser to close the `EventSource`.
+#[utoipa::path(
+    get,
+    path = "/api/build-logs/id/{id}/stream",
+    params(("id" = i64, Path, description = "build log row id")),
+    responses(
+        (status = 200, description = "server-sent event stream; each event's \
+            `data` is a JSON-serialised `BuildLogFrame` \
+            (stdout_append/stderr_append/status/done)",
+            body = String, content_type = "text/event-stream"),
+    ),
+    tag = "build_logs"
+)]
 pub(super) async fn get_build_log_stream(
     State(state): State<AppState>,
     AxumPath(id): AxumPath<i64>,
diff --git a/hive-c0re/src/dashboard/mod.rs b/hive-c0re/src/dashboard/mod.rs
index 5491e8cd..9e2a12e6 100644
--- a/hive-c0re/src/dashboard/mod.rs
+++ b/hive-c0re/src/dashboard/mod.rs
@@ -7,10 +7,8 @@ use std::sync::Arc;
 
 use anyhow::{Context, Result};
 use axum::{
-    Router,
     http::StatusCode,
     response::{IntoResponse, Response},
-    routing::get,
 };
 use utoipa::OpenApi;
 use utoipa_axum::{router::OpenApiRouter, routes};
@@ -120,27 +118,12 @@ pub async fn serve(
 ) -> Result<()> {
     // API-only: the gateway static-serves the dashboard dist and proxies
     // non-static requests here (see hive-gateway.nix). Unmatched paths 404.
-    // Every `#[utoipa::path]`-annotated route is registered further down
-    // via `OpenApiRouter` instead of a plain `.route(...)` call here — see
-    // the `router`/`api` split below. What's left in this plain chain is
-    // exactly the SSE/streaming endpoints utoipa can't model (see the
-    // `ApiDoc` doc comment) plus anything not yet annotated.
-    let app = Router::new()
-        .route(
-            "/api/build-logs/id/{id}/stream",
-            get(build_logs::get_build_log_stream),
-        )
-        .route(
-            "/api/dashboard/stream",
-            get(state_snapshot::dashboard_stream),
-        )
-        .route(
-            "/api/dashboard/history",
-            get(state_snapshot::dashboard_history),
-        )
-        // No static fallback — the gateway owns the dist; unmatched paths 404.
-        ;
-
+    // No static fallback needed here either. Every route (SSE streams
+    // included — `utoipa::path` can document an SSE body as an opaque
+    // `text/event-stream` string, it just can't model individual frame
+    // shapes) is registered below via `OpenApiRouter`; see the `router`/
+    // `api` split.
+    //
     // `routes!()` folds every handler it's given into ONE shared
     // `MethodRouter` for the whole macro invocation — it does NOT group
     // by path internally, so passing it handlers for more than one
@@ -219,7 +202,9 @@ pub async fn serve(
         .routes(routes!(questions::post_cancel_question))
         .routes(routes!(tombstones::post_purge_tombstone))
         .routes(routes!(meta_inputs::post_meta_update))
-        .merge(app.into())
+        .routes(routes!(build_logs::get_build_log_stream))
+        .routes(routes!(state_snapshot::dashboard_stream))
+        .routes(routes!(state_snapshot::dashboard_history))
         .split_for_parts();
     let app = router
         .merge(SwaggerUi::new("/api/docs").url("/api/openapi.json", api))
@@ -453,6 +438,9 @@ mod router_build_probe {
             .routes(routes!(questions::post_answer_question))
             .routes(routes!(questions::post_cancel_question))
             .routes(routes!(tombstones::post_purge_tombstone))
-            .routes(routes!(meta_inputs::post_meta_update));
+            .routes(routes!(meta_inputs::post_meta_update))
+            .routes(routes!(build_logs::get_build_log_stream))
+            .routes(routes!(state_snapshot::dashboard_stream))
+            .routes(routes!(state_snapshot::dashboard_history));
     }
 }
diff --git a/hive-c0re/src/dashboard/state_snapshot.rs b/hive-c0re/src/dashboard/state_snapshot.rs
index 37006cc1..f86000cb 100644
--- a/hive-c0re/src/dashboard/state_snapshot.rs
+++ b/hive-c0re/src/dashboard/state_snapshot.rs
@@ -18,6 +18,7 @@ use hive_sh4re::Approval;
 use serde::{Deserialize, Serialize};
 use tokio_stream::wrappers::BroadcastStream;
 use tokio_stream::{Stream, StreamExt};
+use utoipa::IntoParams;
 
 use crate::container_view::ContainerView;
 
@@ -655,6 +656,17 @@ fn build_approval_views(approvals: Vec<Approval>) -> Vec<ApprovalView> {
     out
 }
 
+#[utoipa::path(
+    get,
+    path = "/api/dashboard/history",
+    responses(
+        (status = 200, description = "`{ seq, events }` — up to the last 200 \
+            broker messages as `DashboardEvent::Sent`/`Delivered` JSON, plus \
+            `seq`: the dashboard channel's high-water mark at fetch time \
+            (used by clients to dedupe against buffered live SSE frames)"),
+    ),
+    tag = "state_snapshot"
+)]
 pub(super) async fn dashboard_history(State(state): State<AppState>) -> Response {
     // Backfill source for the dashboard terminal. Returns up to ~200
     // historical broker messages (no other event kinds are persisted)
@@ -731,7 +743,7 @@ pub(super) async fn dashboard_history(State(state): State<AppState>) -> Response
 /// Useful for narrow pages (e.g. `flow.js` only cares about `sent`
 /// / `delivered` / `container_state_changed` / `container_removed`)
 /// that want to drop the dispatch overhead on every unrelated mutation.
-#[derive(Deserialize, Default)]
+#[derive(Deserialize, Default, IntoParams)]
 pub(super) struct DashboardStreamQuery {
     /// Comma-separated event kinds to forward. Each token is
     /// trimmed; unknown kinds are silently ignored on lookup
@@ -739,6 +751,18 @@ pub(super) struct DashboardStreamQuery {
     kinds: Option<String>,
 }
 
+#[utoipa::path(
+    get,
+    path = "/api/dashboard/stream",
+    params(DashboardStreamQuery),
+    responses(
+        (status = 200, description = "server-sent event stream; each event's \
+            `data` is a JSON-serialised `DashboardEvent` (seq-tagged; pair \
+            with `/api/dashboard/history` to backfill + dedupe on connect)",
+            body = String, content_type = "text/event-stream"),
+    ),
+    tag = "state_snapshot"
+)]
 pub(super) async fn dashboard_stream(
     State(state): State<AppState>,
     axum::extract::Query(q): axum::extract::Query<DashboardStreamQuery>,
diff --git a/hive-c0re/src/meta.rs b/hive-c0re/src/meta.rs
index 080982b9..37ba30da 100644
--- a/hive-c0re/src/meta.rs
+++ b/hive-c0re/src/meta.rs
@@ -85,6 +85,11 @@ async fn stage_generated_meta_files(dir: &std::path::Path) -> Result<()> {
 /// no-op.
 pub async fn sync_agents(hive: &HiveEnv, agents: &[AgentSpec]) -> Result<()> {
     let _guard = META_LOCK.lock().await;
+    // Before anything is written: a hive without a forge URL would deploy a
+    // whole fleet of agents that silently never log in, because the agent
+    // option treats "unset" as "no forge configured" rather than erroring.
+    // This is the layer that knows a forge is mandatory, so it says so here.
+    require_service_urls(&forwarded_env_vars())?;
     let dir = crate::paths::meta_root();
     std::fs::create_dir_all(&dir).with_context(|| format!("create {}", dir.display()))?;
 
@@ -715,8 +720,12 @@ const SERVICE_URL_OPTIONS: &[(&str, &str)] = &[
 /// other under the default parallel test runner. A pure function over the
 /// already-collected pairs has no such hazard.
 ///
-/// A var that isn't present emits nothing rather than a guess — see the call
-/// site for why that silence is the point.
+/// A var that isn't present emits nothing rather than a guess. For an optional
+/// service that is the whole point — the agent option defaults to `null`,
+/// meaning "not configured", and the units that would use it aren't generated.
+/// For a service the hive cannot run without, silence would instead produce a
+/// fleet of agents quietly missing an integration, so those are checked by
+/// [`require_service_urls`] before this is called.
 fn push_service_url_options(out: &mut String, vars: &[(&'static str, String)]) {
     use std::fmt::Write as _;
     for (var, val) in vars {
@@ -728,6 +737,48 @@ fn push_service_url_options(out: &mut String, vars: &[(&'static str, String)]) {
     }
 }
 
+/// Service URLs a running hive must always supply, checked before rendering.
+///
+/// The forge is not optional on a real hive: `hive-c0re.nix` sets
+/// `HIVE_FORGE_URL` unconditionally, so its absence means this daemon was
+/// started outside the NixOS module. The agent option is nullable — `null`
+/// legitimately means "no forge" when the modules are evaluated on their own —
+/// which is exactly why the hive has to assert its own requirement here rather
+/// than leaning on the module to reject the empty case.
+const REQUIRED_SERVICE_URL_VARS: &[&str] = &["HIVE_FORGE_URL"];
+
+/// Fails unless every [`REQUIRED_SERVICE_URL_VARS`] entry is present in
+/// `vars`.
+///
+/// Pure over the already-collected pairs so it can be tested without touching
+/// process env (the same reason [`push_service_url_options`] is split out).
+///
+/// Checked by `sync_agents` — the point at which the hive commits a rendered
+/// flake to disk — rather than inside the renderer. Rendering is a pure string
+/// operation that many tests exercise directly; making *it* env-dependent
+/// would mean every one of those tests either sets a process-wide var (the
+/// parallel-test race this module already avoids) or fails for reasons that
+/// have nothing to do with what it asserts.
+///
+/// # Errors
+///
+/// When a required var is missing. `hive-c0re.nix` sets it unconditionally, so
+/// this means the daemon is running outside the NixOS module; refusing to
+/// write the flake beats writing one whose agents would silently all lack a
+/// forge.
+fn require_service_urls(vars: &[(&'static str, String)]) -> Result<()> {
+    for required in REQUIRED_SERVICE_URL_VARS {
+        if !vars.iter().any(|(name, _)| name == required) {
+            anyhow::bail!(
+                "{required} is unset — hive-c0re.nix sets it unconditionally, so this process \
+                 was started outside the NixOS module. Refusing to write a meta flake whose \
+                 agents would every one of them have no forge configured."
+            );
+        }
+    }
+    Ok(())
+}
+
 fn forwarded_env_vars() -> Vec<(&'static str, String)> {
     FORWARDED_VARS
         .iter()
@@ -1177,10 +1228,16 @@ where
     // ever correct when the callee shares the caller's netns, and the forge
     // and homeserver are moving to swarm level, possibly on other hosts.
     //
-    // Absent vars emit nothing rather than a guess. Once the defaults are
-    // gone that surfaces as an eval failure, which is the point: better a
-    // build that stops than an agent quietly talking to a port on the wrong
-    // machine.
+    // Absent vars emit nothing rather than a guess, and the agent option
+    // treats "unset" as "this service is not configured" rather than
+    // substituting a loopback address — an absent integration instead of a
+    // misdirected one.
+    //
+    // That is the right default for an optional service and the wrong one for
+    // the forge, which a running hive always has — so `sync_agents` rejects a
+    // missing `HIVE_FORGE_URL` before it writes anything (`require_service_urls`).
+    // The check lives there rather than here because rendering is a pure string
+    // operation the tests exercise directly.
     push_service_url_options(&mut out, &forwarded_env_vars());
     // GitHub integration is on by default in every agent
     // (`hyperhive.github.enable`); the host turns it off hive-wide via
@@ -1900,12 +1957,36 @@ mod tests {
         );
     }
 
+    #[test]
+    fn require_service_urls_accepts_a_rendered_forge_url() {
+        require_service_urls(&[
+            ("HIVE_FORGE_URL", "http://forge.example.test".to_string()),
+            ("HYPERHIVE_HIVE_NAME", "pr1ma".to_string()),
+        ])
+        .expect("a forwarded forge URL satisfies the requirement");
+    }
+
+    #[test]
+    fn require_service_urls_refuses_to_write_without_a_forge() {
+        // The agent option is nullable, so nothing downstream would complain:
+        // every agent would simply come up with no forge login and no way to
+        // tell that was unintended. The hive asserts its own requirement
+        // because it is the only layer that knows a forge is mandatory.
+        let err = require_service_urls(&[("HYPERHIVE_HIVE_NAME", "pr1ma".to_string())])
+            .expect_err("a missing forge URL must stop the write");
+        assert!(
+            err.to_string().contains("HIVE_FORGE_URL is unset"),
+            "the error must name the missing variable: {err}"
+        );
+    }
+
     #[test]
     fn service_url_options_emit_nothing_when_absent() {
-        // No guess when the host doesn't say. Once the nix-side defaults are
-        // removed this is what turns a missing value into a build failure
-        // rather than an agent quietly talking to a port on the wrong machine,
-        // so the absence has to be as deliberate as the presence.
+        // No guess when the host doesn't say — the agent option stays `null`
+        // ("not configured") and the units that would use it aren't generated,
+        // so absence is an absent integration rather than a misdirected one.
+        // Required services don't reach here: `require_service_urls` rejects
+        // them first.
         let mut out = String::new();
         push_service_url_options(&mut out, &[("HYPERHIVE_HIVE_NAME", "pr1ma".to_string())]);
         assert!(
diff --git a/nix/agent-modules/forge.nix b/nix/agent-modules/forge.nix
index 0e4eb8e9..a26cf295 100644
--- a/nix/agent-modules/forge.nix
+++ b/nix/agent-modules/forge.nix
@@ -20,7 +20,8 @@ let
 in
 {
   options.hyperhive.forge.url = lib.mkOption {
-    type = lib.types.str;
+    type = lib.types.nullOr lib.types.str;
+    default = null;
     example = "http://forge.internal:3000";
     description = ''
       Base URL of the hyperhive-managed Forgejo. Used at container
@@ -31,28 +32,38 @@ in
       forge-token file is missing (i.e. hive-forge isn't running on
       the host).
 
-      **Required, deliberately undefaulted.** hive-c0re renders it into
-      every agent's config from the host's `HIVE_FORGE_URL`, which
-      `hive-c0re.nix` sets unconditionally --- the forge is mandatory.
-      A loopback default would be a guess: the forge may run on a
-      different host from the agents, and inside an agent's network
-      namespace `localhost` reaches the agent, not the forge. An
-      unevaluatable config is better than one that builds and then
-      talks to the wrong machine.
+      **`null` means "no forge", not "guess one".** There is deliberately
+      no loopback default: the forge may run on a different host from
+      the agents, and inside an agent's network namespace `localhost`
+      reaches the agent rather than the forge, so a default would be a
+      value that builds fine and then talks to the wrong machine.
+      When this is `null` the tea-login and avatar-sync units are not
+      generated at all --- an absent integration, never a misdirected
+      one.
+
+      On a real hive it is always set: hive-c0re renders it into every
+      agent's config from the host's `HIVE_FORGE_URL` (which
+      `hive-c0re.nix` sets unconditionally) and refuses to render a meta
+      flake without it, so `null` only survives where the modules are
+      evaluated outside a hive --- exactly the case that has no forge.
     '';
   };
 
   config = {
     assertions = [
-      # The empty string is the one value the type permits that cannot
-      # be a URL, and it is what a caller supplies when they have
-      # nothing --- exactly the case the removed loopback default used
-      # to paper over. Reject it here so the failure names the option.
+      # Only a *set* value is constrained. `null` is the legitimate
+      # "no forge here" state (see the option doc) and is handled by
+      # not generating the units below, so it must not trip this.
+      # The empty string, by contrast, is the one non-null value the
+      # type permits that cannot be a URL --- it is what a caller
+      # supplies when they have nothing, which is precisely what `null`
+      # is for, so reject it and name the option.
       {
         assertion =
-          lib.hasPrefix "http://" config.hyperhive.forge.url
+          config.hyperhive.forge.url == null
+          || lib.hasPrefix "http://" config.hyperhive.forge.url
           || lib.hasPrefix "https://" config.hyperhive.forge.url;
-        message = "hyperhive.forge.url must be an http:// or https:// URL (got: \"${config.hyperhive.forge.url}\")";
+        message = "hyperhive.forge.url must be an http:// or https:// URL, or null for no forge (got: \"${toString config.hyperhive.forge.url}\")";
       }
     ];
 
@@ -105,7 +116,9 @@ in
     # One-shot: tea config.yml from the seeded forge token. Shape
     # contract (always exit 0, no set -e, skip-silently, re-runnable):
     # docs/conventions.md::Best-effort oneshot services.
-    systemd.services.tea-login = {
+    # Not generated at all when no forge is configured: an absent
+    # integration rather than one pointed at a guessed address.
+    systemd.services.tea-login = lib.mkIf (config.hyperhive.forge.url != null) {
       description = "configure tea CLI from hive-forge token (best-effort)";
       wantedBy = [ "multi-user.target" ];
       after = [ "local-fs.target" ];
@@ -188,49 +201,51 @@ in
     # avatar sync), so the unit only exists when an icon is configured
     # and needs no librsvg at runtime — Forgejo's Go image library
     # can't decode SVG, hence PNG.
-    systemd.services.forge-avatar-sync = lib.mkIf (config.hyperhive.icon != null) {
-      description = "sync agent icon to Forgejo user avatar (best-effort)";
-      wantedBy = [ "multi-user.target" ];
-      after = [ "tea-login.service" ];
-      serviceConfig = {
-        Type = "oneshot";
-        RemainAfterExit = false;
-        # Pin the journal identity (else it's the `script` store-path wrapper).
-        SyslogIdentifier = "forge-avatar-sync";
-      };
-      path = [
-        pkgs.curl
-        pkgs.coreutils
-        pkgs.jq
-      ];
-      script = ''
-        FORGE_URL=${lib.escapeShellArg config.hyperhive.forge.url}
-        # $HYPERHIVE_STATE_DIR is set system-wide by the meta flake
-        # (systemd.globalEnvironment) to `/agents/<name>/state`.
-        TOKEN_FILE="$HYPERHIVE_STATE_DIR/forge-token"
-        if [ ! -f "$TOKEN_FILE" ]; then
-          echo "forge-avatar-sync: no forge-token found; skipping"
-          exit 0
-        fi
-        TOKEN=$(cat "$TOKEN_FILE")
-        IMAGE=$(base64 -w 0 < ${iconPng})
-        # Forgejo POST /user/avatar expects {"image":"<base64>"} — just the
-        # raw base64 string, NOT a data URI (data:image/png;base64,...).
-        # Use jq to build the payload so the large base64 value is safely quoted.
-        PAYLOAD=$(jq -n --arg img "$IMAGE" '{image:$img}')
-        RESP=$(curl -sf --max-time 10 \
-          -X POST "$FORGE_URL/api/v1/user/avatar" \
-          -H "Authorization: token $TOKEN" \
-          -H "Content-Type: application/json" \
-          -d "$PAYLOAD" \
-          -w "\n%{http_code}" 2>/dev/null || true)
-        CODE=$(printf '%s' "$RESP" | tail -1)
-        if [ "$CODE" = "204" ] || [ "$CODE" = "200" ]; then
-          echo "forge-avatar-sync: avatar uploaded (HTTP $CODE)"
-        else
-          echo "forge-avatar-sync: upload returned HTTP $CODE — skipping (non-fatal)"
-        fi
-      '';
-    };
+    systemd.services.forge-avatar-sync =
+      lib.mkIf (config.hyperhive.icon != null && config.hyperhive.forge.url != null)
+        {
+          description = "sync agent icon to Forgejo user avatar (best-effort)";
+          wantedBy = [ "multi-user.target" ];
+          after = [ "tea-login.service" ];
+          serviceConfig = {
+            Type = "oneshot";
+            RemainAfterExit = false;
+            # Pin the journal identity (else it's the `script` store-path wrapper).
+            SyslogIdentifier = "forge-avatar-sync";
+          };
+          path = [
+            pkgs.curl
+            pkgs.coreutils
+            pkgs.jq
+          ];
+          script = ''
+            FORGE_URL=${lib.escapeShellArg config.hyperhive.forge.url}
+            # $HYPERHIVE_STATE_DIR is set system-wide by the meta flake
+            # (systemd.globalEnvironment) to `/agents/<name>/state`.
+            TOKEN_FILE="$HYPERHIVE_STATE_DIR/forge-token"
+            if [ ! -f "$TOKEN_FILE" ]; then
+              echo "forge-avatar-sync: no forge-token found; skipping"
+              exit 0
+            fi
+            TOKEN=$(cat "$TOKEN_FILE")
+            IMAGE=$(base64 -w 0 < ${iconPng})
+            # Forgejo POST /user/avatar expects {"image":"<base64>"} — just the
+            # raw base64 string, NOT a data URI (data:image/png;base64,...).
+            # Use jq to build the payload so the large base64 value is safely quoted.
+            PAYLOAD=$(jq -n --arg img "$IMAGE" '{image:$img}')
+            RESP=$(curl -sf --max-time 10 \
+              -X POST "$FORGE_URL/api/v1/user/avatar" \
+              -H "Authorization: token $TOKEN" \
+              -H "Content-Type: application/json" \
+              -d "$PAYLOAD" \
+              -w "\n%{http_code}" 2>/dev/null || true)
+            CODE=$(printf '%s' "$RESP" | tail -1)
+            if [ "$CODE" = "204" ] || [ "$CODE" = "200" ]; then
+              echo "forge-avatar-sync: avatar uploaded (HTTP $CODE)"
+            else
+              echo "forge-avatar-sync: upload returned HTTP $CODE — skipping (non-fatal)"
+            fi
+          '';
+        };
   };
 }