diff --git a/backend/app/api/routes/printers.py b/backend/app/api/routes/printers.py
index 8e3a9f0..97282f3 100644
--- a/backend/app/api/routes/printers.py
+++ b/backend/app/api/routes/printers.py
@@ -102,6 +102,41 @@ async def list_printers(session: SessionDep) -> list[PrinterRead]:
     return result
 
 
+# ---------------------------------------------------------------------------
+# GET /api/printers/{id}
+# ---------------------------------------------------------------------------
+
+
+@router.get(
+    "/{printer_id}",
+    response_model=PrinterRead,
+    summary="Get printer detail",
+    description=(
+        "Returns full metadata for a single printer, including the ``paused`` "
+        "flag joined from ``printer_state``. Returns 404 when the printer is "
+        "not registered."
+    ),
+)
+async def get_printer(
+    printer_id: UUID,
+    session: SessionDep,
+) -> PrinterRead:
+    """Return full printer metadata for a single printer."""
+    printer = await _get_printer_or_404(session, printer_id)
+    state = await printer_state_repo.get(session, printer_id)
+    return PrinterRead(
+        id=printer.id,
+        name=printer.name,
+        model=printer.model,
+        backend=printer.backend,
+        connection=dict(printer.connection),
+        enabled=printer.enabled,
+        paused=state.paused if state is not None else False,
+        created_at=printer.created_at,
+        updated_at=printer.updated_at,
+    )
+
+
 # ---------------------------------------------------------------------------
 # GET /api/printers/{id}/status
 # ---------------------------------------------------------------------------
diff --git a/backend/app/api/routes/templates.py b/backend/app/api/routes/templates.py
index 0abf431..462a64a 100644
--- a/backend/app/api/routes/templates.py
+++ b/backend/app/api/routes/templates.py
@@ -1,11 +1,15 @@
-"""REST endpoint for the Templates aggregate (Phase 6a Task 2).
-
-Single read-only endpoint — template CRUD is out of scope for Phase 6a.
+"""REST endpoints for the Templates aggregate (Phase 6a Task 2 + Bug-3 fix).
 
 Routes
 ------
-GET /api/templates?app=<optional> — list all templates, optionally filtered
-    by integration app (snipeit, grocy, spoolman, …)
+GET  /api/templates?app=<optional>         — list all templates, optionally
+    filtered by integration app (snipeit, grocy, spoolman, …)
+POST /api/render/preview?key=<template_key> — render a sample label as PNG
+
+The preview endpoint is used by the frontend template-detail page to show a
+rendered preview image. Sample values are sourced from the template's own
+``preview_sample`` block in its definition — the route does NOT fabricate
+sample data. Templates without ``preview_sample`` return HTTP 422.
 
 References:
     docs/superpowers/specs/2026-05-16-phase6a-rest-api-design.md — Templates section
@@ -14,21 +18,203 @@
 
 from __future__ import annotations
 
-from typing import Annotated
+import asyncio
+import io
+import logging
+from typing import Annotated, Any
 
-from fastapi import APIRouter, Depends, Query
+from fastapi import APIRouter, Depends, HTTPException, Query, Request
+from fastapi.responses import Response
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.db.session import get_session
 from app.repositories import templates as templates_repo
+from app.schemas.label_data import LabelData
+from app.schemas.template import TemplateSchema
 from app.schemas.template_read import TemplateRead
+from app.services.label_renderer import LabelRenderer
+
+_log = logging.getLogger(__name__)
 
 router = APIRouter(prefix="/api/templates", tags=["templates"])
 
+# Separate router for /api/render so the preview endpoint can live here while
+# the prefix keeps it at /api/render/preview (not /api/templates/render/preview).
+render_router = APIRouter(prefix="/api/render", tags=["templates"])
+
 # Type alias for the session dependency
 SessionDep = Annotated[AsyncSession, Depends(get_session)]
 
 
+def _build_label_data(
+    template_key: str,
+    template_app: str | None,
+    preview_sample: dict[str, Any],
+) -> LabelData:
+    """Build a LabelData from a template's preview_sample dict.
+
+    The template is responsible for declaring values for every ``field``
+    and ``data_field`` its elements reference. Missing values raise
+    HTTPException 422.
+    """
+    try:
+        # source_app is filled from the template's own ``app`` field — falls
+        # back to "generic" for templates without an integration.
+        return LabelData(
+            primary_id=str(preview_sample.get("primary_id", "")),
+            title=str(preview_sample.get("title", "")),
+            qr_payload=str(preview_sample.get("qr_payload", "")),
+            source_app=template_app or "generic",
+            secondary=tuple(preview_sample.get("secondary", ()) or ()),
+        )
+    except Exception as exc:  # ValidationError or coercion error
+        raise HTTPException(
+            status_code=422,
+            detail=(f"Template {template_key!r} has an invalid preview_sample block: {exc}"),
+        ) from exc
+
+
+# LabelData fields that preview_sample values map to (via _build_label_data).
+# Elements reference these by name via `field` / `data_field` on LayoutElement.
+_LABEL_DATA_FIELDS: frozenset[str] = frozenset({"primary_id", "title", "qr_payload", "secondary"})
+
+
+def _validate_preview_sample_fields(
+    template_key: str,
+    elements: tuple[Any, ...],
+    preview_sample: dict[str, Any],
+) -> None:
+    """Raise HTTP 422 if preview_sample is missing any field required by elements.
+
+    Each LayoutElement of type ``text`` references a ``field`` on LabelData;
+    type ``qr`` references a ``data_field``. Both must be present in
+    ``preview_sample`` so the renderer does not silently produce empty output.
+    """
+    element_fields = set()
+    for el in elements:
+        if el.type == "text" and el.field:
+            element_fields.add(el.field)
+        elif el.type == "qr" and el.data_field:
+            element_fields.add(el.data_field)
+
+    # Restrict check to known LabelData fields — unknown names will resolve to
+    # empty strings via _resolve_field (getattr fallback) which is acceptable.
+    missing = (element_fields & _LABEL_DATA_FIELDS) - set(preview_sample.keys())
+    if missing:
+        raise HTTPException(
+            status_code=422,
+            detail=(
+                f"Template {template_key!r} preview_sample is missing fields "
+                f"required by its elements: {sorted(missing)}. "
+                "Add these keys to the template's 'preview_sample' block."
+            ),
+        )
+
+
+@render_router.post(
+    "/preview",
+    response_class=Response,
+    responses={
+        200: {
+            "content": {"image/png": {"schema": {"type": "string", "format": "binary"}}},
+            "description": "PNG image of the rendered sample label",
+        }
+    },
+    summary="Render a template preview as PNG",
+    description=(
+        "Renders the named template with the sample values declared in the "
+        "template's own ``preview_sample`` block and returns a PNG image. "
+        "Returns 404 if the template key is not registered. "
+        "Returns 422 if the template has no ``preview_sample`` block."
+    ),
+)
+async def render_preview(
+    request: Request,
+    session: SessionDep,
+    key: str = Query(description="Template key, e.g. 'snipeit-12mm'"),
+) -> Response:
+    """Render a sample preview PNG for the given template key.
+
+    Sample values are taken from the template's own ``preview_sample`` block
+    (in ``template.definition``). Templates that do not declare one return
+    HTTP 422 with a clear error message — the route does NOT fabricate
+    fallback sample data.
+
+    The LabelRenderer is reused from ``app.state.label_renderer`` (wired by
+    the lifespan) to avoid per-request font-loading overhead. The CPU-bound
+    render + PNG encode is offloaded to ``asyncio.to_thread`` so it does not
+    block the event loop.
+    """
+    template_row = await templates_repo.get_by_key(session, key)
+    if template_row is None:
+        raise HTTPException(status_code=404, detail=f"template {key!r} not found")
+
+    definition = dict(template_row.definition)
+
+    # The preview_sample block lives in the template definition. Without it
+    # the template cannot be previewed — we refuse to guess on its behalf.
+    preview_sample = definition.get("preview_sample")
+    if not preview_sample or not isinstance(preview_sample, dict):
+        raise HTTPException(
+            status_code=422,
+            detail=(
+                f"Template {template_row.key!r} has no preview_sample in its "
+                "definition. Add a 'preview_sample' block to the template YAML "
+                "to enable previews."
+            ),
+        )
+
+    # Reconstruct TemplateSchema from the DB row — the definition column stores
+    # the TemplateSchema field values. Supplement missing fields from the row's
+    # top-level columns (id→key, tape_mm→tape_width_mm, etc.) so that rows
+    # created before the definition was normalised can still render.
+    schema_dict = dict(definition)
+    schema_dict.setdefault("id", template_row.key)
+    schema_dict.setdefault("name", template_row.name)
+    schema_dict.setdefault("app", template_row.app)
+    schema_dict.setdefault("tape_mm", template_row.tape_width_mm)
+    schema_dict.setdefault("schema_version", template_row.schema_version)
+    schema_dict.setdefault("elements", [])
+
+    try:
+        template_schema = TemplateSchema(**schema_dict)
+    except Exception as exc:
+        # Log the sanitised key from the DB row (trusted), NOT the raw query
+        # parameter, to prevent log injection via crafted key values.
+        _log.warning("render_preview: invalid definition for key=%r: %s", template_row.key, exc)
+        raise HTTPException(status_code=422, detail=f"invalid template definition: {exc}") from exc
+
+    # Validate that preview_sample provides all fields referenced by elements.
+    _validate_preview_sample_fields(template_row.key, template_schema.elements, preview_sample)
+
+    sample_data = _build_label_data(template_row.key, template_row.app, preview_sample)
+
+    # Reuse the shared renderer from app.state (avoids per-request font-loading).
+    # Fall back to a fresh instance when running outside a full lifespan
+    # (e.g. unit tests that don't wire app.state).
+    renderer: LabelRenderer = getattr(request.app.state, "label_renderer", None) or LabelRenderer()
+
+    def _render_and_encode() -> bytes:
+        """CPU-bound render + PNG encode — runs in a thread pool."""
+        try:
+            img = renderer.render(template_schema, sample_data)
+        except ValueError as exc:
+            # Log the sanitised key from the DB row (trusted), NOT the raw query
+            # parameter, to prevent log injection via crafted key values.
+            _log.warning("render_preview: render failed for key=%r: %s", template_row.key, exc)
+            raise
+        buf = io.BytesIO()
+        img.save(buf, format="PNG")
+        return buf.getvalue()
+
+    try:
+        png_bytes = await asyncio.to_thread(_render_and_encode)
+    except ValueError as exc:
+        raise HTTPException(status_code=422, detail=str(exc)) from exc
+
+    return Response(content=png_bytes, media_type="image/png")
+
+
 @router.get(
     "",
     response_model=list[TemplateRead],
diff --git a/backend/app/main.py b/backend/app/main.py
index 007f6b6..0a6c1bd 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -325,9 +325,14 @@ async def lifespan(app: FastAPI) -> AsyncIterator[None]:
     app.state.printer_id = printer.id
     app.state.printer_host = discovery_host
     app.state.printer_snmp_community = settings.printer_snmp_community
+    # Shared LabelRenderer reused by both PrintService and the preview endpoint.
+    # Constructing it once avoids repeated font-loading overhead on every
+    # POST /api/render/preview request.
+    shared_renderer = LabelRenderer()
+    app.state.label_renderer = shared_renderer
     app.state.print_service = PrintService(
         template_loader=TemplateLoader,
-        renderer=LabelRenderer(),
+        renderer=shared_renderer,
         print_queue=queue,
         lookup_service=AppLookupService(),
         printer_id=printer.id,
@@ -589,6 +594,7 @@ async def readiness(
     app.include_router(events_routes.router)
     app.include_router(printers_routes.router)
     app.include_router(templates_routes.router)
+    app.include_router(templates_routes.render_router)
     app.include_router(jobs_routes.router)
     app.include_router(lookup_routes.router)
     app.include_router(webhooks_routes.router)
diff --git a/backend/app/schemas/printer.py b/backend/app/schemas/printer.py
index 8cf5785..01d6227 100644
--- a/backend/app/schemas/printer.py
+++ b/backend/app/schemas/printer.py
@@ -32,7 +32,7 @@ class PrinterRead(BaseModel):
     backend: str
     connection: dict[str, object]
     enabled: bool
-    paused: bool = False  # joined from printer_state
+    paused: bool  # joined from printer_state — always set explicitly by callers
     created_at: datetime
     updated_at: datetime
 
diff --git a/backend/app/schemas/template.py b/backend/app/schemas/template.py
index ce69be6..34d280d 100644
--- a/backend/app/schemas/template.py
+++ b/backend/app/schemas/template.py
@@ -6,6 +6,11 @@
 
 Templates are frozen at construction so they can be safely seeded as
 module-level constants (see app/seed/templates.py in PR D2).
+
+Immutability note: Pydantic `frozen=True` prevents attribute re-assignment
+but does NOT deep-freeze container values. The ``preview_sample`` field
+therefore uses ``tuple[str, ...]`` for its sequence type (instead of
+``list[str]``) so the entire schema is truly immutable after construction.
 """
 
 from __future__ import annotations
@@ -61,6 +66,14 @@ class TemplateSchema(BaseModel):
     validated at load time against ``IntegrationRegistry``; the schema
     itself accepts any string so plugins can be added without a schema
     migration.
+
+    ``preview_sample`` is an optional mapping of field name → sample value
+    used by the preview-render endpoint (``POST /api/render/preview``).
+    Each template declares its own preview values so the route never has
+    to fabricate sample data per-app. Keys must match the ``field`` /
+    ``data_field`` names referenced by ``elements``; supported keys are
+    ``primary_id``, ``title``, ``qr_payload``, and optionally ``secondary``
+    (list/tuple of additional lines).
     """
 
     model_config = ConfigDict(frozen=True)
@@ -71,3 +84,7 @@ class TemplateSchema(BaseModel):
     app: str | None
     tape_mm: int
     elements: tuple[LayoutElement, ...]
+    # Values use tuple (not list) so the entire schema is deeply immutable —
+    # Pydantic frozen=True only prevents attribute re-assignment, not mutation
+    # of mutable containers stored in those attributes.
+    preview_sample: dict[str, str | int | float | bool | tuple[str, ...]] | None = None
diff --git a/backend/app/seed/templates/grocy-12mm.yaml b/backend/app/seed/templates/grocy-12mm.yaml
index 09ff3a5..ea2554c 100644
--- a/backend/app/seed/templates/grocy-12mm.yaml
+++ b/backend/app/seed/templates/grocy-12mm.yaml
@@ -9,3 +9,7 @@ elements:
   - { type: qr,   x: 8,   y: 13, size: 80, data_field: qr_payload }
   - { type: text, x: 100, y: 18, field: primary_id, font_size: 22 }
   - { type: text, x: 100, y: 60, field: title,      font_size: 14 }
+preview_sample:
+  primary_id: "Erdbeermarmelade"
+  title: "Lager > Vorrat"
+  qr_payload: "https://grocy.example.com/stock/products/47"
diff --git a/backend/app/seed/templates/grocy-18mm.yaml b/backend/app/seed/templates/grocy-18mm.yaml
index c74f05c..50115c5 100644
--- a/backend/app/seed/templates/grocy-18mm.yaml
+++ b/backend/app/seed/templates/grocy-18mm.yaml
@@ -9,3 +9,8 @@ elements:
   - { type: text, x: 170, y: 20,  field: primary_id, font_size: 32 }
   - { type: text, x: 170, y: 70,  field: title,      font_size: 20 }
   - { type: text, x: 170, y: 110, field: secondary,  font_size: 14 }
+preview_sample:
+  primary_id: "Erdbeermarmelade"
+  title: "Lager > Vorrat"
+  qr_payload: "https://grocy.example.com/stock/products/47"
+  secondary: ["MHD 2027-04-30", "3 Glaeser"]
diff --git a/backend/app/seed/templates/grocy-24mm.yaml b/backend/app/seed/templates/grocy-24mm.yaml
index 4de59fa..db996a0 100644
--- a/backend/app/seed/templates/grocy-24mm.yaml
+++ b/backend/app/seed/templates/grocy-24mm.yaml
@@ -9,3 +9,8 @@ elements:
   - { type: text, x: 260, y: 20,  field: primary_id, font_size: 48 }
   - { type: text, x: 260, y: 85,  field: title,      font_size: 28 }
   - { type: text, x: 260, y: 130, field: secondary,  font_size: 18 }
+preview_sample:
+  primary_id: "Erdbeermarmelade"
+  title: "Lager > Vorrat"
+  qr_payload: "https://grocy.example.com/stock/products/47"
+  secondary: ["MHD 2027-04-30", "3 Glaeser"]
diff --git a/backend/app/seed/templates/qr-only-12mm.yaml b/backend/app/seed/templates/qr-only-12mm.yaml
index 97b70bc..8505e35 100644
--- a/backend/app/seed/templates/qr-only-12mm.yaml
+++ b/backend/app/seed/templates/qr-only-12mm.yaml
@@ -6,3 +6,7 @@ app: null
 tape_mm: 12
 elements:
   - { type: qr, x: 260, y: 13, size: 80, data_field: qr_payload }
+preview_sample:
+  primary_id: "Sample"
+  title: "Preview"
+  qr_payload: "https://example.com/preview"
diff --git a/backend/app/seed/templates/qr-only-18mm.yaml b/backend/app/seed/templates/qr-only-18mm.yaml
index e44dcd3..393960c 100644
--- a/backend/app/seed/templates/qr-only-18mm.yaml
+++ b/backend/app/seed/templates/qr-only-18mm.yaml
@@ -6,3 +6,7 @@ app: null
 tape_mm: 18
 elements:
   - { type: qr, x: 230, y: 13, size: 140, data_field: qr_payload }
+preview_sample:
+  primary_id: "Sample"
+  title: "Preview"
+  qr_payload: "https://example.com/preview"
diff --git a/backend/app/seed/templates/qr-only-24mm.yaml b/backend/app/seed/templates/qr-only-24mm.yaml
index 8324a25..cdb739b 100644
--- a/backend/app/seed/templates/qr-only-24mm.yaml
+++ b/backend/app/seed/templates/qr-only-24mm.yaml
@@ -6,3 +6,7 @@ app: null
 tape_mm: 24
 elements:
   - { type: qr, x: 185, y: 13, size: 230, data_field: qr_payload }
+preview_sample:
+  primary_id: "Sample"
+  title: "Preview"
+  qr_payload: "https://example.com/preview"
diff --git a/backend/app/seed/templates/snipeit-12mm.yaml b/backend/app/seed/templates/snipeit-12mm.yaml
index b85c94d..b231054 100644
--- a/backend/app/seed/templates/snipeit-12mm.yaml
+++ b/backend/app/seed/templates/snipeit-12mm.yaml
@@ -9,3 +9,7 @@ elements:
   - { type: qr,   x: 8,   y: 13, size: 80, data_field: qr_payload }
   - { type: text, x: 100, y: 18, field: primary_id, font_size: 22 }
   - { type: text, x: 100, y: 60, field: title,      font_size: 14 }
+preview_sample:
+  primary_id: "ASSET-2024-001"
+  title: "Dell Latitude 7430"
+  qr_payload: "https://snipeit.example.com/hardware/123"
diff --git a/backend/app/seed/templates/snipeit-18mm.yaml b/backend/app/seed/templates/snipeit-18mm.yaml
index a041716..edba27f 100644
--- a/backend/app/seed/templates/snipeit-18mm.yaml
+++ b/backend/app/seed/templates/snipeit-18mm.yaml
@@ -9,3 +9,8 @@ elements:
   - { type: text, x: 170, y: 20,  field: primary_id, font_size: 32 }
   - { type: text, x: 170, y: 70,  field: title,      font_size: 20 }
   - { type: text, x: 170, y: 110, field: secondary,  font_size: 14 }
+preview_sample:
+  primary_id: "ASSET-2024-001"
+  title: "Dell Latitude 7430"
+  qr_payload: "https://snipeit.example.com/hardware/123"
+  secondary: ["IT Office", "Bjoern Strausmann"]
diff --git a/backend/app/seed/templates/snipeit-24mm.yaml b/backend/app/seed/templates/snipeit-24mm.yaml
index 453fabd..7a2c312 100644
--- a/backend/app/seed/templates/snipeit-24mm.yaml
+++ b/backend/app/seed/templates/snipeit-24mm.yaml
@@ -9,3 +9,8 @@ elements:
   - { type: text, x: 260, y: 20,  field: primary_id, font_size: 48 }
   - { type: text, x: 260, y: 85,  field: title,      font_size: 28 }
   - { type: text, x: 260, y: 130, field: secondary,  font_size: 18 }
+preview_sample:
+  primary_id: "ASSET-2024-001"
+  title: "Dell Latitude 7430"
+  qr_payload: "https://snipeit.example.com/hardware/123"
+  secondary: ["IT Office", "Bjoern Strausmann"]
diff --git a/backend/app/seed/templates/spoolman-12mm.yaml b/backend/app/seed/templates/spoolman-12mm.yaml
index 2e3d8f3..f8b192b 100644
--- a/backend/app/seed/templates/spoolman-12mm.yaml
+++ b/backend/app/seed/templates/spoolman-12mm.yaml
@@ -8,3 +8,7 @@ elements:
   - { type: qr,   x: 8,   y: 13, size: 80, data_field: qr_payload }
   - { type: text, x: 100, y: 18, field: primary_id, font_size: 22 }
   - { type: text, x: 100, y: 60, field: title,      font_size: 14 }
+preview_sample:
+  primary_id: "PLA-Black-1kg"
+  title: "Spool #7"
+  qr_payload: "https://spoolman.example.com/spool/7"
diff --git a/backend/app/seed/templates/spoolman-18mm.yaml b/backend/app/seed/templates/spoolman-18mm.yaml
index 1b63efa..c793702 100644
--- a/backend/app/seed/templates/spoolman-18mm.yaml
+++ b/backend/app/seed/templates/spoolman-18mm.yaml
@@ -9,3 +9,8 @@ elements:
   - { type: text, x: 170, y: 20,  field: primary_id, font_size: 32 }
   - { type: text, x: 170, y: 70,  field: title,      font_size: 20 }
   - { type: text, x: 170, y: 110, field: secondary,  font_size: 14 }
+preview_sample:
+  primary_id: "PLA-Black-1kg"
+  title: "Spool #7"
+  qr_payload: "https://spoolman.example.com/spool/7"
+  secondary: ["780g left", "Prusament"]
diff --git a/backend/app/seed/templates/spoolman-24mm.yaml b/backend/app/seed/templates/spoolman-24mm.yaml
index a571e90..1950bb4 100644
--- a/backend/app/seed/templates/spoolman-24mm.yaml
+++ b/backend/app/seed/templates/spoolman-24mm.yaml
@@ -9,3 +9,8 @@ elements:
   - { type: text, x: 260, y: 20,  field: primary_id, font_size: 48 }
   - { type: text, x: 260, y: 85,  field: title,      font_size: 28 }
   - { type: text, x: 260, y: 130, field: secondary,  font_size: 18 }
+preview_sample:
+  primary_id: "PLA-Black-1kg"
+  title: "Spool #7"
+  qr_payload: "https://spoolman.example.com/spool/7"
+  secondary: ["780g left", "Prusament"]
diff --git a/backend/tests/unit/api/test_printers_routes.py b/backend/tests/unit/api/test_printers_routes.py
index 3ff8dc1..93d0868 100644
--- a/backend/tests/unit/api/test_printers_routes.py
+++ b/backend/tests/unit/api/test_printers_routes.py
@@ -892,6 +892,53 @@ async def test_get_printer_tape_direct_unknown_tape_size_raises_404(session) ->
     assert exc_info.value.status_code == 404
 
 
+@pytest.mark.asyncio
+async def test_get_printer_detail_returns_full_metadata(session) -> None:
+    """GET /api/printers/{id} returns full printer metadata including paused flag.
+
+    Regression for Bug 2 — the backend had no single-printer GET endpoint.
+    The frontend detail page showed only Status + Tape + Error, no metadata.
+    """
+    printer = await _make_printer(session)
+    await _make_printer_state(session, printer.id, paused=False)
+
+    app = _build_app(session)
+    client = TestClient(app, raise_server_exceptions=True)
+    r = client.get(f"/api/printers/{printer.id}")
+
+    assert r.status_code == 200
+    body = r.json()
+    required_fields = (
+        "id",
+        "name",
+        "model",
+        "backend",
+        "connection",
+        "enabled",
+        "paused",
+        "created_at",
+        "updated_at",
+    )
+    for field in required_fields:
+        assert field in body, f"missing field: {field}"
+    assert body["connection"]["host"] == "198.51.100.10"
+    assert body["connection"]["port"] == 9100
+    assert body["paused"] is False
+
+
+@pytest.mark.asyncio
+async def test_get_printer_detail_unknown_id_returns_404(session) -> None:
+    """GET /api/printers/{id} returns 404 for an unknown UUID."""
+    from uuid import uuid4
+
+    app = _build_app(session)
+    client = TestClient(app, raise_server_exceptions=True)
+    r = client.get(f"/api/printers/{uuid4()}")
+
+    assert r.status_code == 404
+    assert "not found" in r.json()["detail"]
+
+
 @pytest.mark.asyncio
 async def test_get_printer_queue_direct_returns_active_jobs(session) -> None:
     """get_printer_queue called directly returns QUEUED and PRINTING jobs.
diff --git a/backend/tests/unit/api/test_templates_routes.py b/backend/tests/unit/api/test_templates_routes.py
index 3468f8c..f1aab62 100644
--- a/backend/tests/unit/api/test_templates_routes.py
+++ b/backend/tests/unit/api/test_templates_routes.py
@@ -12,7 +12,7 @@
 import app.models  # noqa: F401 — registers all SQLModel tables with metadata
 import pytest
 import pytest_asyncio
-from app.api.routes.templates import router
+from app.api.routes.templates import render_router, router
 from app.db.engine import _apply_pragmas
 from app.db.session import get_session
 from app.models.template import Template
@@ -58,6 +58,7 @@ def _build_app(session_override: AsyncSession) -> FastAPI:
     """Return a FastAPI app with the templates router and the DB overridden."""
     app = FastAPI()
     app.include_router(router)
+    app.include_router(render_router)
 
     async def _override_session() -> AsyncIterator[AsyncSession]:
         yield session_override
@@ -77,7 +78,11 @@ async def _make_template(
     name: str,
     app_name: str | None = None,
     source: str = "seed",
+    preview_sample: dict[str, object] | None = None,
 ) -> Template:
+    definition: dict[str, object] = {"elements": []}
+    if preview_sample is not None:
+        definition["preview_sample"] = preview_sample
     tpl = Template(
         key=key,
         name=name,
@@ -85,7 +90,7 @@ async def _make_template(
         printer_model="PT-P750W",
         tape_width_mm=12,
         source=source,
-        definition={"elements": []},
+        definition=definition,
     )
     session.add(tpl)
     await session.commit()
@@ -194,6 +199,136 @@ async def test_list_templates_direct_with_app_filter(session) -> None:
     assert result[0].app == "snipeit"
 
 
+@pytest.mark.asyncio
+async def test_template_preview_returns_png(session) -> None:
+    """POST /api/render/preview?key=<key> renders a sample label as PNG bytes.
+
+    Regression for Bug 3 — the backend had no preview endpoint.
+    The frontend template detail page fell back to preview-placeholder.svg
+    because POST /api/render/preview always returned 404.
+    """
+    await _make_template(
+        session,
+        "snipeit/asset",
+        "Asset Label",
+        app_name="snipeit",
+        preview_sample={
+            "primary_id": "ASSET-2024-001",
+            "title": "Dell Latitude 7430",
+            "qr_payload": "https://snipeit.example.com/hardware/123",
+        },
+    )
+
+    app = _build_app(session)
+    client = TestClient(app, raise_server_exceptions=True)
+    r = client.post("/api/render/preview?key=snipeit%2Fasset")
+
+    assert r.status_code == 200
+    assert r.headers["content-type"] == "image/png"
+    assert r.content[:8] == b"\x89PNG\r\n\x1a\n"  # PNG magic number
+
+
+@pytest.mark.asyncio
+async def test_template_preview_unknown_key_returns_404(session) -> None:
+    """POST /api/render/preview?key=<unknown> returns 404 for a missing template."""
+    app = _build_app(session)
+    client = TestClient(app, raise_server_exceptions=True)
+    r = client.post("/api/render/preview?key=no-such-key")
+
+    assert r.status_code == 404
+
+
+@pytest.mark.asyncio
+async def test_template_preview_uses_preview_sample_from_definition(session) -> None:
+    """The preview endpoint reads sample values from template.definition.preview_sample.
+
+    Regression for Commit 4 refactor — sample data must live in the template
+    definition, not be hardcoded per-app in the route. A template without
+    preview_sample must return 422; a template WITH preview_sample renders.
+    """
+    await _make_template(
+        session,
+        "custom/key",
+        "Custom Template",
+        app_name=None,  # no integration app — only works because preview_sample is on the template
+        preview_sample={
+            "primary_id": "CUSTOM-1",
+            "title": "User-defined preview",
+            "qr_payload": "https://example.com/custom/1",
+        },
+    )
+
+    app = _build_app(session)
+    client = TestClient(app, raise_server_exceptions=True)
+    r = client.post("/api/render/preview?key=custom%2Fkey")
+
+    assert r.status_code == 200
+    assert r.headers["content-type"] == "image/png"
+    assert r.content[:8] == b"\x89PNG\r\n\x1a\n"
+
+
+@pytest.mark.asyncio
+async def test_template_preview_renders_seed_template_via_loader_pipeline(session) -> None:
+    """End-to-end: a real seed YAML survives the TemplateLoader → seed_db pipeline
+    with its preview_sample intact, and the preview endpoint renders it.
+
+    This guards against silent loss of preview_sample if a future refactor
+    breaks the schema_dump → DB → schema_construct round-trip.
+    """
+    from pathlib import Path
+
+    from app.integrations import _discover_plugins
+    from app.integrations.registry import IntegrationRegistry
+    from app.services.template_loader import TemplateLoader
+
+    # IntegrationRegistry is a class-level singleton that other tests may have
+    # cleared. The seed-template loader validates `app` against the registry,
+    # so re-discover plugins here to make the test hermetic regardless of
+    # test ordering in the full suite.
+    if not IntegrationRegistry.names():
+        _discover_plugins()
+
+    seed_dir = Path(__file__).resolve().parents[3] / "app" / "seed" / "templates"
+    # The loader caches at the class level — clear first so the test is hermetic.
+    TemplateLoader._cache.clear()
+    TemplateLoader.load_dir(seed_dir)
+    await TemplateLoader.seed_db(session)
+
+    app = _build_app(session)
+    client = TestClient(app, raise_server_exceptions=True)
+    r = client.post("/api/render/preview?key=snipeit-12mm")
+
+    assert r.status_code == 200, r.text
+    assert r.headers["content-type"] == "image/png"
+    assert r.content[:8] == b"\x89PNG\r\n\x1a\n"
+
+
+@pytest.mark.asyncio
+async def test_template_preview_fails_when_template_lacks_preview_sample(session) -> None:
+    """Templates without preview_sample return 422 with a clear error message.
+
+    The previous implementation guessed sample data per-app — wrong responsibility
+    locality. Templates must declare their own preview values; the route no
+    longer fabricates fallbacks.
+    """
+    await _make_template(
+        session,
+        "incomplete/template",
+        "No Preview Sample",
+        app_name="snipeit",
+        preview_sample=None,  # explicit: definition has no preview_sample block
+    )
+
+    app = _build_app(session)
+    client = TestClient(app, raise_server_exceptions=True)
+    r = client.post("/api/render/preview?key=incomplete%2Ftemplate")
+
+    assert r.status_code == 422
+    detail = r.json()["detail"]
+    assert "preview_sample" in detail
+    assert "incomplete/template" in detail
+
+
 @pytest.mark.asyncio
 async def test_list_templates_direct_filter_no_match_returns_empty(session) -> None:
     """list_templates with ?app= that matches nothing returns an empty list.
diff --git a/frontend/internal/api/client.gen.go b/frontend/internal/api/client.gen.go
index 49a6146..6021d06 100644
--- a/frontend/internal/api/client.gen.go
+++ b/frontend/internal/api/client.gen.go
@@ -114,7 +114,7 @@ type PrinterRead struct {
 	Id         openapi_types.UUID     `json:"id"`
 	Model      string                 `json:"model"`
 	Name       string                 `json:"name"`
-	Paused     *bool                  `json:"paused,omitempty"`
+	Paused     bool                   `json:"paused"`
 	UpdatedAt  time.Time              `json:"updated_at"`
 }
 
@@ -221,6 +221,12 @@ type ListJobsApiJobsGetParams struct {
 // LookupApiLookupAppEntityIdGetParamsApp defines parameters for LookupApiLookupAppEntityIdGet.
 type LookupApiLookupAppEntityIdGetParamsApp string
 
+// RenderPreviewApiRenderPreviewPostParams defines parameters for RenderPreviewApiRenderPreviewPost.
+type RenderPreviewApiRenderPreviewPostParams struct {
+	// Key Template key, e.g. 'snipeit-12mm'
+	Key string `form:"key" json:"key"`
+}
+
 // ListTemplatesApiTemplatesGetParams defines parameters for ListTemplatesApiTemplatesGet.
 type ListTemplatesApiTemplatesGetParams struct {
 	// App Filter by integration app (snipeit / grocy / spoolman / …)
@@ -389,6 +395,9 @@ type ClientInterface interface {
 	// ListPrintersApiPrintersGet request
 	ListPrintersApiPrintersGet(ctx context.Context, reqEditors ...RequestEditorFn) (*http.Response, error)
 
+	// GetPrinterApiPrintersPrinterIdGet request
+	GetPrinterApiPrintersPrinterIdGet(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*http.Response, error)
+
 	// PausePrinterApiPrintersPrinterIdPausePost request
 	PausePrinterApiPrintersPrinterIdPausePost(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*http.Response, error)
 
@@ -407,6 +416,9 @@ type ClientInterface interface {
 	// GetPrinterTapeApiPrintersPrinterIdTapeGet request
 	GetPrinterTapeApiPrintersPrinterIdTapeGet(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*http.Response, error)
 
+	// RenderPreviewApiRenderPreviewPost request
+	RenderPreviewApiRenderPreviewPost(ctx context.Context, params *RenderPreviewApiRenderPreviewPostParams, reqEditors ...RequestEditorFn) (*http.Response, error)
+
 	// ListTemplatesApiTemplatesGet request
 	ListTemplatesApiTemplatesGet(ctx context.Context, params *ListTemplatesApiTemplatesGetParams, reqEditors ...RequestEditorFn) (*http.Response, error)
 }
@@ -519,6 +531,18 @@ func (c *Client) ListPrintersApiPrintersGet(ctx context.Context, reqEditors ...R
 	return c.Client.Do(req)
 }
 
+func (c *Client) GetPrinterApiPrintersPrinterIdGet(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*http.Response, error) {
+	req, err := NewGetPrinterApiPrintersPrinterIdGetRequest(c.Server, printerId)
+	if err != nil {
+		return nil, err
+	}
+	req = req.WithContext(ctx)
+	if err := c.applyEditors(ctx, req, reqEditors); err != nil {
+		return nil, err
+	}
+	return c.Client.Do(req)
+}
+
 func (c *Client) PausePrinterApiPrintersPrinterIdPausePost(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*http.Response, error) {
 	req, err := NewPausePrinterApiPrintersPrinterIdPausePostRequest(c.Server, printerId)
 	if err != nil {
@@ -591,6 +615,18 @@ func (c *Client) GetPrinterTapeApiPrintersPrinterIdTapeGet(ctx context.Context,
 	return c.Client.Do(req)
 }
 
+func (c *Client) RenderPreviewApiRenderPreviewPost(ctx context.Context, params *RenderPreviewApiRenderPreviewPostParams, reqEditors ...RequestEditorFn) (*http.Response, error) {
+	req, err := NewRenderPreviewApiRenderPreviewPostRequest(c.Server, params)
+	if err != nil {
+		return nil, err
+	}
+	req = req.WithContext(ctx)
+	if err := c.applyEditors(ctx, req, reqEditors); err != nil {
+		return nil, err
+	}
+	return c.Client.Do(req)
+}
+
 func (c *Client) ListTemplatesApiTemplatesGet(ctx context.Context, params *ListTemplatesApiTemplatesGetParams, reqEditors ...RequestEditorFn) (*http.Response, error) {
 	req, err := NewListTemplatesApiTemplatesGetRequest(c.Server, params)
 	if err != nil {
@@ -981,6 +1017,40 @@ func NewListPrintersApiPrintersGetRequest(server string) (*http.Request, error)
 	return req, nil
 }
 
+// NewGetPrinterApiPrintersPrinterIdGetRequest generates requests for GetPrinterApiPrintersPrinterIdGet
+func NewGetPrinterApiPrintersPrinterIdGetRequest(server string, printerId openapi_types.UUID) (*http.Request, error) {
+	var err error
+
+	var pathParam0 string
+
+	pathParam0, err = runtime.StyleParamWithOptions("simple", false, "printer_id", printerId, runtime.StyleParamOptions{ParamLocation: runtime.ParamLocationPath, Type: "string", Format: "uuid"})
+	if err != nil {
+		return nil, err
+	}
+
+	serverURL, err := url.Parse(server)
+	if err != nil {
+		return nil, err
+	}
+
+	operationPath := fmt.Sprintf("/api/printers/%s", pathParam0)
+	if operationPath[0] == '/' {
+		operationPath = "." + operationPath
+	}
+
+	queryURL, err := serverURL.Parse(operationPath)
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequest(http.MethodGet, queryURL.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	return req, nil
+}
+
 // NewPausePrinterApiPrintersPrinterIdPausePostRequest generates requests for PausePrinterApiPrintersPrinterIdPausePost
 func NewPausePrinterApiPrintersPrinterIdPausePostRequest(server string, printerId openapi_types.UUID) (*http.Request, error) {
 	var err error
@@ -1185,6 +1255,56 @@ func NewGetPrinterTapeApiPrintersPrinterIdTapeGetRequest(server string, printerI
 	return req, nil
 }
 
+// NewRenderPreviewApiRenderPreviewPostRequest generates requests for RenderPreviewApiRenderPreviewPost
+func NewRenderPreviewApiRenderPreviewPostRequest(server string, params *RenderPreviewApiRenderPreviewPostParams) (*http.Request, error) {
+	var err error
+
+	serverURL, err := url.Parse(server)
+	if err != nil {
+		return nil, err
+	}
+
+	operationPath := fmt.Sprintf("/api/render/preview")
+	if operationPath[0] == '/' {
+		operationPath = "." + operationPath
+	}
+
+	queryURL, err := serverURL.Parse(operationPath)
+	if err != nil {
+		return nil, err
+	}
+
+	if params != nil {
+		// queryValues collects non-styled parameters (passthrough, JSON)
+		// that are safe to round-trip through url.Values.Encode().
+		queryValues := queryURL.Query()
+		// rawQueryFragments collects pre-encoded query fragments from
+		// styled parameters, preserving literal commas as delimiters
+		// per the OpenAPI spec (e.g. "color=blue,black,brown").
+		var rawQueryFragments []string
+
+		if queryFrag, err := runtime.StyleParamWithOptions("form", true, "key", params.Key, runtime.StyleParamOptions{ParamLocation: runtime.ParamLocationQuery, Type: "string", Format: ""}); err != nil {
+			return nil, err
+		} else {
+			for _, qp := range strings.Split(queryFrag, "&") {
+				rawQueryFragments = append(rawQueryFragments, qp)
+			}
+		}
+
+		if encoded := queryValues.Encode(); encoded != "" {
+			rawQueryFragments = append(rawQueryFragments, encoded)
+		}
+		queryURL.RawQuery = strings.Join(rawQueryFragments, "&")
+	}
+
+	req, err := http.NewRequest(http.MethodPost, queryURL.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	return req, nil
+}
+
 // NewListTemplatesApiTemplatesGetRequest generates requests for ListTemplatesApiTemplatesGet
 func NewListTemplatesApiTemplatesGetRequest(server string, params *ListTemplatesApiTemplatesGetParams) (*http.Request, error) {
 	var err error
@@ -1309,6 +1429,9 @@ type ClientWithResponsesInterface interface {
 	// ListPrintersApiPrintersGetWithResponse request
 	ListPrintersApiPrintersGetWithResponse(ctx context.Context, reqEditors ...RequestEditorFn) (*ListPrintersApiPrintersGetResponse, error)
 
+	// GetPrinterApiPrintersPrinterIdGetWithResponse request
+	GetPrinterApiPrintersPrinterIdGetWithResponse(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*GetPrinterApiPrintersPrinterIdGetResponse, error)
+
 	// PausePrinterApiPrintersPrinterIdPausePostWithResponse request
 	PausePrinterApiPrintersPrinterIdPausePostWithResponse(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*PausePrinterApiPrintersPrinterIdPausePostResponse, error)
 
@@ -1327,6 +1450,9 @@ type ClientWithResponsesInterface interface {
 	// GetPrinterTapeApiPrintersPrinterIdTapeGetWithResponse request
 	GetPrinterTapeApiPrintersPrinterIdTapeGetWithResponse(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*GetPrinterTapeApiPrintersPrinterIdTapeGetResponse, error)
 
+	// RenderPreviewApiRenderPreviewPostWithResponse request
+	RenderPreviewApiRenderPreviewPostWithResponse(ctx context.Context, params *RenderPreviewApiRenderPreviewPostParams, reqEditors ...RequestEditorFn) (*RenderPreviewApiRenderPreviewPostResponse, error)
+
 	// ListTemplatesApiTemplatesGetWithResponse request
 	ListTemplatesApiTemplatesGetWithResponse(ctx context.Context, params *ListTemplatesApiTemplatesGetParams, reqEditors ...RequestEditorFn) (*ListTemplatesApiTemplatesGetResponse, error)
 }
@@ -1608,6 +1734,37 @@ func (r ListPrintersApiPrintersGetResponse) ContentType() string {
 	return ""
 }
 
+type GetPrinterApiPrintersPrinterIdGetResponse struct {
+	Body         []byte
+	HTTPResponse *http.Response
+	JSON200      *PrinterRead
+	JSON422      *HTTPValidationError
+}
+
+// Status returns HTTPResponse.Status
+func (r GetPrinterApiPrintersPrinterIdGetResponse) Status() string {
+	if r.HTTPResponse != nil {
+		return r.HTTPResponse.Status
+	}
+	return http.StatusText(0)
+}
+
+// StatusCode returns HTTPResponse.StatusCode
+func (r GetPrinterApiPrintersPrinterIdGetResponse) StatusCode() int {
+	if r.HTTPResponse != nil {
+		return r.HTTPResponse.StatusCode
+	}
+	return 0
+}
+
+// ContentType is a convenience method to retrieve the Content-Type value from the HTTP response headers
+func (r GetPrinterApiPrintersPrinterIdGetResponse) ContentType() string {
+	if r.HTTPResponse != nil {
+		return r.HTTPResponse.Header.Get("Content-Type")
+	}
+	return ""
+}
+
 type PausePrinterApiPrintersPrinterIdPausePostResponse struct {
 	Body         []byte
 	HTTPResponse *http.Response
@@ -1791,6 +1948,36 @@ func (r GetPrinterTapeApiPrintersPrinterIdTapeGetResponse) ContentType() string
 	return ""
 }
 
+type RenderPreviewApiRenderPreviewPostResponse struct {
+	Body         []byte
+	HTTPResponse *http.Response
+	JSON422      *HTTPValidationError
+}
+
+// Status returns HTTPResponse.Status
+func (r RenderPreviewApiRenderPreviewPostResponse) Status() string {
+	if r.HTTPResponse != nil {
+		return r.HTTPResponse.Status
+	}
+	return http.StatusText(0)
+}
+
+// StatusCode returns HTTPResponse.StatusCode
+func (r RenderPreviewApiRenderPreviewPostResponse) StatusCode() int {
+	if r.HTTPResponse != nil {
+		return r.HTTPResponse.StatusCode
+	}
+	return 0
+}
+
+// ContentType is a convenience method to retrieve the Content-Type value from the HTTP response headers
+func (r RenderPreviewApiRenderPreviewPostResponse) ContentType() string {
+	if r.HTTPResponse != nil {
+		return r.HTTPResponse.Header.Get("Content-Type")
+	}
+	return ""
+}
+
 type ListTemplatesApiTemplatesGetResponse struct {
 	Body         []byte
 	HTTPResponse *http.Response
@@ -1903,6 +2090,15 @@ func (c *ClientWithResponses) ListPrintersApiPrintersGetWithResponse(ctx context
 	return ParseListPrintersApiPrintersGetResponse(rsp)
 }
 
+// GetPrinterApiPrintersPrinterIdGetWithResponse request returning *GetPrinterApiPrintersPrinterIdGetResponse
+func (c *ClientWithResponses) GetPrinterApiPrintersPrinterIdGetWithResponse(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*GetPrinterApiPrintersPrinterIdGetResponse, error) {
+	rsp, err := c.GetPrinterApiPrintersPrinterIdGet(ctx, printerId, reqEditors...)
+	if err != nil {
+		return nil, err
+	}
+	return ParseGetPrinterApiPrintersPrinterIdGetResponse(rsp)
+}
+
 // PausePrinterApiPrintersPrinterIdPausePostWithResponse request returning *PausePrinterApiPrintersPrinterIdPausePostResponse
 func (c *ClientWithResponses) PausePrinterApiPrintersPrinterIdPausePostWithResponse(ctx context.Context, printerId openapi_types.UUID, reqEditors ...RequestEditorFn) (*PausePrinterApiPrintersPrinterIdPausePostResponse, error) {
 	rsp, err := c.PausePrinterApiPrintersPrinterIdPausePost(ctx, printerId, reqEditors...)
@@ -1957,6 +2153,15 @@ func (c *ClientWithResponses) GetPrinterTapeApiPrintersPrinterIdTapeGetWithRespo
 	return ParseGetPrinterTapeApiPrintersPrinterIdTapeGetResponse(rsp)
 }
 
+// RenderPreviewApiRenderPreviewPostWithResponse request returning *RenderPreviewApiRenderPreviewPostResponse
+func (c *ClientWithResponses) RenderPreviewApiRenderPreviewPostWithResponse(ctx context.Context, params *RenderPreviewApiRenderPreviewPostParams, reqEditors ...RequestEditorFn) (*RenderPreviewApiRenderPreviewPostResponse, error) {
+	rsp, err := c.RenderPreviewApiRenderPreviewPost(ctx, params, reqEditors...)
+	if err != nil {
+		return nil, err
+	}
+	return ParseRenderPreviewApiRenderPreviewPostResponse(rsp)
+}
+
 // ListTemplatesApiTemplatesGetWithResponse request returning *ListTemplatesApiTemplatesGetResponse
 func (c *ClientWithResponses) ListTemplatesApiTemplatesGetWithResponse(ctx context.Context, params *ListTemplatesApiTemplatesGetParams, reqEditors ...RequestEditorFn) (*ListTemplatesApiTemplatesGetResponse, error) {
 	rsp, err := c.ListTemplatesApiTemplatesGet(ctx, params, reqEditors...)
@@ -2249,6 +2454,39 @@ func ParseListPrintersApiPrintersGetResponse(rsp *http.Response) (*ListPrintersA
 	return response, nil
 }
 
+// ParseGetPrinterApiPrintersPrinterIdGetResponse parses an HTTP response from a GetPrinterApiPrintersPrinterIdGetWithResponse call
+func ParseGetPrinterApiPrintersPrinterIdGetResponse(rsp *http.Response) (*GetPrinterApiPrintersPrinterIdGetResponse, error) {
+	bodyBytes, err := io.ReadAll(rsp.Body)
+	defer func() { _ = rsp.Body.Close() }()
+	if err != nil {
+		return nil, err
+	}
+
+	response := &GetPrinterApiPrintersPrinterIdGetResponse{
+		Body:         bodyBytes,
+		HTTPResponse: rsp,
+	}
+
+	switch {
+	case strings.Contains(rsp.Header.Get("Content-Type"), "json") && rsp.StatusCode == 200:
+		var dest PrinterRead
+		if err := json.Unmarshal(bodyBytes, &dest); err != nil {
+			return nil, err
+		}
+		response.JSON200 = &dest
+
+	case strings.Contains(rsp.Header.Get("Content-Type"), "json") && rsp.StatusCode == 422:
+		var dest HTTPValidationError
+		if err := json.Unmarshal(bodyBytes, &dest); err != nil {
+			return nil, err
+		}
+		response.JSON422 = &dest
+
+	}
+
+	return response, nil
+}
+
 // ParsePausePrinterApiPrintersPrinterIdPausePostResponse parses an HTTP response from a PausePrinterApiPrintersPrinterIdPausePostWithResponse call
 func ParsePausePrinterApiPrintersPrinterIdPausePostResponse(rsp *http.Response) (*PausePrinterApiPrintersPrinterIdPausePostResponse, error) {
 	bodyBytes, err := io.ReadAll(rsp.Body)
@@ -2426,6 +2664,32 @@ func ParseGetPrinterTapeApiPrintersPrinterIdTapeGetResponse(rsp *http.Response)
 	return response, nil
 }
 
+// ParseRenderPreviewApiRenderPreviewPostResponse parses an HTTP response from a RenderPreviewApiRenderPreviewPostWithResponse call
+func ParseRenderPreviewApiRenderPreviewPostResponse(rsp *http.Response) (*RenderPreviewApiRenderPreviewPostResponse, error) {
+	bodyBytes, err := io.ReadAll(rsp.Body)
+	defer func() { _ = rsp.Body.Close() }()
+	if err != nil {
+		return nil, err
+	}
+
+	response := &RenderPreviewApiRenderPreviewPostResponse{
+		Body:         bodyBytes,
+		HTTPResponse: rsp,
+	}
+
+	switch {
+	case strings.Contains(rsp.Header.Get("Content-Type"), "json") && rsp.StatusCode == 422:
+		var dest HTTPValidationError
+		if err := json.Unmarshal(bodyBytes, &dest); err != nil {
+			return nil, err
+		}
+		response.JSON422 = &dest
+
+	}
+
+	return response, nil
+}
+
 // ParseListTemplatesApiTemplatesGetResponse parses an HTTP response from a ListTemplatesApiTemplatesGetWithResponse call
 func ParseListTemplatesApiTemplatesGetResponse(rsp *http.Response) (*ListTemplatesApiTemplatesGetResponse, error) {
 	bodyBytes, err := io.ReadAll(rsp.Body)
diff --git a/frontend/internal/api/client.go b/frontend/internal/api/client.go
index 5ac2bd0..b64c690 100644
--- a/frontend/internal/api/client.go
+++ b/frontend/internal/api/client.go
@@ -76,6 +76,27 @@ func (c *HubClient) ListPrinters(ctx context.Context) ([]PrinterRead, error) {
 	return *resp.JSON200, nil
 }
 
+// GetPrinterDetail returns full printer metadata from GET /api/printers/{id}.
+func (c *HubClient) GetPrinterDetail(ctx context.Context, id string) (*PrinterRead, error) {
+	start := time.Now()
+	uid, err := parseUUID(id)
+	if err != nil {
+		return nil, ErrNotFound
+	}
+	resp, err := c.gen.GetPrinterApiPrintersPrinterIdGetWithResponse(ctx, uid)
+	logCall("GetPrinterDetail", start, err)
+	if err != nil {
+		return nil, err
+	}
+	if resp.StatusCode() == http.StatusNotFound {
+		return nil, ErrNotFound
+	}
+	if resp.JSON200 == nil {
+		return nil, fmt.Errorf("GetPrinterDetail: status %d", resp.StatusCode())
+	}
+	return resp.JSON200, nil
+}
+
 // GetPrinterStatus returns a fresh printer status probe from GET /api/printers/{id}/status.
 func (c *HubClient) GetPrinterStatus(ctx context.Context, id string) (*PrinterStatus, error) {
 	start := time.Now()
diff --git a/frontend/internal/api/client_test.go b/frontend/internal/api/client_test.go
index 4287459..efa8739 100644
--- a/frontend/internal/api/client_test.go
+++ b/frontend/internal/api/client_test.go
@@ -11,6 +11,47 @@ import (
 	"github.com/strausmann/label-printer-hub/frontend/internal/api"
 )
 
+// TestPrinterReadPausedFalseDecodesAsBoolFalse verifies that a JSON response
+// with "paused": false decodes to PrinterRead.Paused == false (not a non-nil
+// pointer to false, which would be truthy in Go template {{if .Paused}}).
+//
+// This is the regression test for Bug 1: oapi-codegen generated Paused *bool
+// (omitempty) from the OpenAPI schema that listed paused as optional-with-default.
+// A non-nil *bool(&false) evaluates as truthy in html/template {{if .Paused}},
+// causing every printer to show the "Paused" badge.
+// After the fix: paused is required in the schema → Paused bool → false is falsy.
+func TestPrinterReadPausedFalseDecodesAsBoolFalse(t *testing.T) {
+	t.Parallel()
+	now := time.Now().Format(time.RFC3339)
+	backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/api/printers" {
+			w.Header().Set("Content-Type", "application/json")
+			json.NewEncoder(w).Encode([]map[string]any{
+				{"id": "aaaaaaaa-0000-0000-0000-000000000001", "name": "PT-P750W",
+					"model": "pt_series", "backend": "tcp",
+					"connection": map[string]any{"host": "198.51.100.10", "port": 9100},
+					"enabled":    true, "paused": false, "created_at": now, "updated_at": now},
+			})
+		} else {
+			http.NotFound(w, r)
+		}
+	}))
+	defer backend.Close()
+
+	printers, err := api.NewHubClient(backend.URL).ListPrinters(context.Background())
+	if err != nil {
+		t.Fatalf("ListPrinters: %v", err)
+	}
+	if len(printers) != 1 {
+		t.Fatalf("expected 1 printer, got %d", len(printers))
+	}
+	// Paused must be a plain bool false — NOT a non-nil *bool(&false).
+	// A *bool is truthy in html/template {{if .Paused}} even when it points to false.
+	if printers[0].Paused != false {
+		t.Errorf("Paused = %v, want false (plain bool, not pointer-to-false)", printers[0].Paused)
+	}
+}
+
 func TestListPrintersHitsCorrectPath(t *testing.T) {
 	t.Parallel()
 	called := false
diff --git a/frontend/internal/api/openapi.snapshot.json b/frontend/internal/api/openapi.snapshot.json
index 797dc52..8ad96ce 100644
--- a/frontend/internal/api/openapi.snapshot.json
+++ b/frontend/internal/api/openapi.snapshot.json
@@ -1,7 +1,7 @@
 {
   "openapi": "3.0.3",
   "info": {
-    "title": "Label Printer Hub — backend",
+    "title": "Label Printer Hub \u2014 backend",
     "version": "0.0.0-dev"
   },
   "paths": {
@@ -176,7 +176,7 @@
           "printers"
         ],
         "summary": "Pause job dispatch for a printer",
-        "description": "Sets ``printer_state.paused = true`` for this printer.  New jobs can still be queued but the worker will not dispatch them until the printer is resumed.  Idempotent — pausing an already-paused printer returns 204 without error.",
+        "description": "Sets ``printer_state.paused = true`` for this printer.  New jobs can still be queued but the worker will not dispatch them until the printer is resumed.  Idempotent \u2014 pausing an already-paused printer returns 204 without error.",
         "operationId": "pause_printer_api_printers__printer_id__pause_post",
         "parameters": [
           {
@@ -213,7 +213,7 @@
           "printers"
         ],
         "summary": "Resume job dispatch for a printer",
-        "description": "Sets ``printer_state.paused = false``.  Idempotent — resuming an already-active printer returns 204 without error.",
+        "description": "Sets ``printer_state.paused = false``.  Idempotent \u2014 resuming an already-active printer returns 204 without error.",
         "operationId": "resume_printer_api_printers__printer_id__resume_post",
         "parameters": [
           {
@@ -250,7 +250,7 @@
           "printers"
         ],
         "summary": "Cancel all queued jobs for a printer",
-        "description": "Bulk-cancels every job in ``queued`` state for this printer.  Jobs in ``printing`` state are intentionally **not** cancelled — a mid-print abort is unsafe over TCP/9100 because the raster data is already on the wire.  Returns 204 even when there are no queued jobs.",
+        "description": "Bulk-cancels every job in ``queued`` state for this printer.  Jobs in ``printing`` state are intentionally **not** cancelled \u2014 a mid-print abort is unsafe over TCP/9100 because the raster data is already on the wire.  Returns 204 even when there are no queued jobs.",
         "operationId": "clear_printer_queue_api_printers__printer_id__queue_clear_post",
         "parameters": [
           {
@@ -295,12 +295,12 @@
             "in": "query",
             "required": false,
             "schema": {
-              "description": "Filter by integration app (snipeit / grocy / spoolman / …)",
+              "description": "Filter by integration app (snipeit / grocy / spoolman / \u2026)",
               "title": "App",
               "type": "string",
               "nullable": true
             },
-            "description": "Filter by integration app (snipeit / grocy / spoolman / …)"
+            "description": "Filter by integration app (snipeit / grocy / spoolman / \u2026)"
           }
         ],
         "responses": {
@@ -345,12 +345,12 @@
             "in": "query",
             "required": false,
             "schema": {
-              "description": "Filter by job state (queued / printing / done / failed / …)",
+              "description": "Filter by job state (queued / printing / done / failed / \u2026)",
               "title": "State",
               "type": "string",
               "nullable": true
             },
-            "description": "Filter by job state (queued / printing / done / failed / …)"
+            "description": "Filter by job state (queued / printing / done / failed / \u2026)"
           },
           {
             "name": "printer_id",
@@ -471,7 +471,7 @@
           "jobs"
         ],
         "summary": "Cancel a queued job",
-        "description": "Cancels a job that is in ``queued`` state.  Returns 409 ProblemDetail when the job is in ``printing`` (or any other non-QUEUED) state — mid-print abort is unsafe over TCP/9100 because the raster data is already on the wire.",
+        "description": "Cancels a job that is in ``queued`` state.  Returns 409 ProblemDetail when the job is in ``printing`` (or any other non-QUEUED) state \u2014 mid-print abort is unsafe over TCP/9100 because the raster data is already on the wire.",
         "operationId": "cancel_job_api_jobs__job_id__cancel_post",
         "parameters": [
           {
@@ -515,7 +515,7 @@
           "jobs"
         ],
         "summary": "Pause a job (not yet implemented)",
-        "description": "Placeholder — returns 501 ProblemDetail.  Mid-job pause will be implemented when the queue worker gains control-plane support for pausing an in-progress raster stream.  This endpoint exists so the Phase 7 UI can wire to a stable URL.",
+        "description": "Placeholder \u2014 returns 501 ProblemDetail.  Mid-job pause will be implemented when the queue worker gains control-plane support for pausing an in-progress raster stream.  This endpoint exists so the Phase 7 UI can wire to a stable URL.",
         "operationId": "pause_job_api_jobs__job_id__pause_post",
         "parameters": [
           {
@@ -559,7 +559,7 @@
           "jobs"
         ],
         "summary": "Resume a paused job (not yet implemented)",
-        "description": "Placeholder — returns 501 ProblemDetail.  Resume will be implemented alongside pause in a later phase.  This endpoint exists so the Phase 7 UI can wire to a stable URL.",
+        "description": "Placeholder \u2014 returns 501 ProblemDetail.  Resume will be implemented alongside pause in a later phase.  This endpoint exists so the Phase 7 UI can wire to a stable URL.",
         "operationId": "resume_job_api_jobs__job_id__resume_post",
         "parameters": [
           {
@@ -647,7 +647,7 @@
           "lookup"
         ],
         "summary": "Resolve an integration entity",
-        "description": "Looks up an entity from the given integration app by its identifier.  ``app`` must be one of ``snipeit``, ``grocy``, or ``spoolman`` — an unsupported value returns 422.  Returns 404 ProblemDetail when the entity does not exist in the integration's backend.  The ``url`` field is the deep-link to the entity in the integration's own web UI, suitable for embedding in a QR code or label.",
+        "description": "Looks up an entity from the given integration app by its identifier.  ``app`` must be one of ``snipeit``, ``grocy``, or ``spoolman`` \u2014 an unsupported value returns 422.  Returns 404 ProblemDetail when the entity does not exist in the integration's backend.  The ``url`` field is the deep-link to the entity in the integration's own web UI, suitable for embedding in a QR code or label.",
         "operationId": "lookup_api_lookup__app___entity_id__get",
         "parameters": [
           {
@@ -705,7 +705,7 @@
           "events"
         ],
         "summary": "Server-Sent Events stream for a printer",
-        "description": "Returns a ``text/event-stream`` response. Publishes ``job.state_changed``, ``printer.status``, and ``printer.tape_changed`` events as they occur. A keepalive comment is sent every 30 s when no events flow. Closes automatically after 5 minutes of inactivity. On reconnect the stream starts fresh — ``Last-Event-ID`` is observed but replay is deferred to Phase 7. Returns 404 if ``printer_id`` does not exist in the database. Returns 429 if the per-printer subscriber limit is reached.",
+        "description": "Returns a ``text/event-stream`` response. Publishes ``job.state_changed``, ``printer.status``, and ``printer.tape_changed`` events as they occur. A keepalive comment is sent every 30 s when no events flow. Closes automatically after 5 minutes of inactivity. On reconnect the stream starts fresh \u2014 ``Last-Event-ID`` is observed but replay is deferred to Phase 7. Returns 404 if ``printer_id`` does not exist in the database. Returns 429 if the per-printer subscriber limit is reached.",
         "operationId": "sse_events_api_events_get",
         "parameters": [
           {
@@ -735,6 +735,99 @@
           }
         }
       }
+    },
+    "/api/printers/{printer_id}": {
+      "get": {
+        "tags": [
+          "printers"
+        ],
+        "summary": "Get printer detail",
+        "description": "Returns full metadata for a single printer, including the ``paused`` flag joined from ``printer_state``. Returns 404 when the printer is not registered.",
+        "operationId": "get_printer_api_printers__printer_id__get",
+        "parameters": [
+          {
+            "name": "printer_id",
+            "in": "path",
+            "required": true,
+            "schema": {
+              "type": "string",
+              "format": "uuid",
+              "title": "Printer Id"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Successful Response",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/PrinterRead"
+                }
+              }
+            }
+          },
+          "422": {
+            "description": "Validation Error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/HTTPValidationError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/api/render/preview": {
+      "post": {
+        "tags": [
+          "templates"
+        ],
+        "summary": "Render a template preview as PNG",
+        "description": "Renders the named template with the sample values declared in the template's own ``preview_sample`` block and returns a PNG image. Returns 404 if the template key is not registered. Returns 422 if the template has no ``preview_sample`` block.",
+        "operationId": "render_preview_api_render_preview_post",
+        "parameters": [
+          {
+            "name": "key",
+            "in": "query",
+            "required": true,
+            "schema": {
+              "description": "Template key, e.g. 'snipeit-12mm'",
+              "title": "Key",
+              "type": "string"
+            },
+            "description": "Template key, e.g. 'snipeit-12mm'"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "PNG image of the rendered sample label",
+            "content": {
+              "image/png": {
+                "schema": {
+                  "type": "string",
+                  "format": "binary"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "Template not found"
+          },
+          "422": {
+            "description": "Validation Error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/HTTPValidationError"
+                }
+              }
+            }
+          }
+        }
+      }
     }
   },
   "components": {
@@ -859,7 +952,7 @@
             "additionalProperties": true,
             "type": "object",
             "title": "Extra",
-            "description": "Integration-specific extras not covered by the core fields. Contents vary by app — see each integration's plugin docs."
+            "description": "Integration-specific extras not covered by the core fields. Contents vary by app \u2014 see each integration's plugin docs."
           }
         },
         "type": "object",
@@ -902,8 +995,7 @@
           },
           "paused": {
             "type": "boolean",
-            "title": "Paused",
-            "default": false
+            "title": "Paused"
           },
           "created_at": {
             "type": "string",
@@ -925,10 +1017,11 @@
           "connection",
           "enabled",
           "created_at",
-          "updated_at"
+          "updated_at",
+          "paused"
         ],
         "title": "PrinterRead",
-        "description": "Full representation of a Printer row, augmented with the paused flag.\n\n``paused`` is joined from the ``printer_state`` table; it defaults to\n``False`` for printers whose state row was not yet created (safe — the\nDB lifespan helper creates state rows at startup, so this only matters\nin tests or during the very first boot)."
+        "description": "Full representation of a Printer row, augmented with the paused flag.\n\n``paused`` is joined from the ``printer_state`` table; it defaults to\n``False`` for printers whose state row was not yet created (safe \u2014 the\nDB lifespan helper creates state rows at startup, so this only matters\nin tests or during the very first boot)."
       },
       "PrinterStatus": {
         "properties": {
diff --git a/frontend/internal/handlers/base.go b/frontend/internal/handlers/base.go
index 5d2cfa3..28e8ba6 100644
--- a/frontend/internal/handlers/base.go
+++ b/frontend/internal/handlers/base.go
@@ -183,7 +183,7 @@ var stubPageContent = map[string]string{
 	"dashboard": `{{define "content"}}<div id="printer-grid"></div>{{end}}
 {{define "dashboard-content"}}<div id="printer-grid">{{range .Printers}}<span>{{.Name}}</span>{{end}}</div>{{end}}`,
 	"printer": `{{define "content"}}<div id="printer-detail">printer</div>{{end}}
-{{define "printer-content"}}<div id="printer-detail">printer</div>{{end}}`,
+{{define "printer-content"}}{{if .Printer}}<div id="printer-detail" data-model="{{.Printer.Model}}" data-enabled="{{.Printer.Enabled}}">{{if and (index .Printer.Connection "host") (index .Printer.Connection "port")}}<span class="host-port">{{index .Printer.Connection "host"}}:{{index .Printer.Connection "port"}}</span>{{else if index .Printer.Connection "interface"}}<span class="usb-badge">{{index .Printer.Connection "interface"}}</span>{{end}}</div>{{else}}<div id="printer-detail">printer</div>{{end}}{{end}}`,
 	"jobs": `{{define "content"}}<div id="jobs-table-container"></div>{{end}}
 {{define "jobs-content"}}<div id="jobs-table-container">{{range .Jobs}}<span class="badge-{{.State}}">{{.State}}</span>{{end}}</div>{{end}}`,
 	"job": `{{define "content"}}<div id="job-detail">job</div>{{end}}
diff --git a/frontend/internal/handlers/dashboard_test.go b/frontend/internal/handlers/dashboard_test.go
index 6aab855..8d234a6 100644
--- a/frontend/internal/handlers/dashboard_test.go
+++ b/frontend/internal/handlers/dashboard_test.go
@@ -74,6 +74,57 @@ func TestDashboardOKFullPage(t *testing.T) {
 	}
 }
 
+func TestDashboardRendersOnlineBadgeWhenPausedFalse(t *testing.T) {
+	// Regression for Bug 1 — dashboard showed "Paused" badge for every printer
+	// because oapi-codegen generated Paused *bool (omitempty) from the OpenAPI
+	// spec that listed paused as optional-with-default. A non-nil pointer to
+	// false evaluates as truthy in {{if .Paused}}, so every printer showed the
+	// Paused badge regardless of the actual paused value.
+	// After the fix: paused is required in the schema → oapi-codegen emits
+	// Paused bool → {{if .Paused}} is false for false, and the badge is correct.
+	//
+	// Strengthened assertions (Round 2): verify that:
+	//   - both printer names appear (data round-trips)
+	//   - no Go pointer nil-value artefact appears in the output
+	//   - the printer-grid wrapper is present (structural sanity)
+	t.Parallel()
+	backend := printersBackend(t)
+	defer backend.Close()
+	ph := handlers.NewPageHandlerFromURL(t, backend.URL)
+
+	req := httptest.NewRequest(http.MethodGet, "/", nil)
+	req.Header.Set("HX-Request", "true")
+	w := httptest.NewRecorder()
+	ph.Dashboard(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("status %d", w.Code)
+	}
+	body := w.Body.String()
+
+	// The stub dashboard-content template renders <span>Name</span> for each printer.
+	// The real badge logic lives in the real template; here we verify the data
+	// round-trips correctly: Paused must be a plain bool so the handler's data
+	// struct can be inspected via the stub template that accesses .Printers.
+	// The mock backend sends paused=false for PT-P750W and paused=true for QL-800.
+	if !strings.Contains(body, "PT-P750W") {
+		t.Errorf("body missing PT-P750W (paused=false printer), got: %s", body)
+	}
+	if !strings.Contains(body, "QL-800") {
+		t.Errorf("body missing QL-800 (paused=true printer), got: %s", body)
+	}
+
+	// The printer grid wrapper must be present — confirms the fragment was rendered.
+	if !strings.Contains(body, "printer-grid") {
+		t.Errorf("body missing printer-grid wrapper: %s", body)
+	}
+
+	// Guard against *bool pointer nil-value rendering — a regression indicator.
+	if strings.Contains(body, "<nil>") {
+		t.Errorf("body contains <nil>: Paused is likely a *bool not dereferenced: %s", body)
+	}
+}
+
 func TestDashboard503WhenBackendDown(t *testing.T) {
 	t.Parallel()
 	backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
diff --git a/frontend/internal/handlers/printer.go b/frontend/internal/handlers/printer.go
index 0f3dbfd..46dcd1b 100644
--- a/frontend/internal/handlers/printer.go
+++ b/frontend/internal/handlers/printer.go
@@ -13,6 +13,7 @@ import (
 type PrinterDetailData struct {
 	TemplateData
 	PrinterID string
+	Printer   *api.PrinterRead   // metadata from GET /api/printers/{id}
 	Status    *api.PrinterStatus
 	Tape      map[string]any
 	Queue     []map[string]any
@@ -24,20 +25,30 @@ func (h *PageHandler) PrinterDetail(w http.ResponseWriter, r *http.Request) {
 	h.PrinterDetailWithID(w, r, chi.URLParam(r, "id"))
 }
 
-// PrinterDetailWithID fetches printer status, tape, and queue in parallel using
-// errgroup and renders the printer detail template.
+// PrinterDetailWithID fetches printer detail, status, tape, and queue in parallel
+// using errgroup and renders the printer detail template.
 // Exported so integration tests can call it directly with a known ID.
 func (h *PageHandler) PrinterDetailWithID(w http.ResponseWriter, r *http.Request, id string) {
 	var (
-		status *api.PrinterStatus
-		tape   map[string]any
-		queue  []map[string]any
+		printer *api.PrinterRead
+		status  *api.PrinterStatus
+		tape    map[string]any
+		queue   []map[string]any
 	)
 
 	g, ctx := errgroup.WithContext(r.Context())
 
+	g.Go(func() (err error) {
+		printer, err = h.client.GetPrinterDetail(ctx, id)
+		return
+	})
 	g.Go(func() (err error) {
 		status, err = h.client.GetPrinterStatus(ctx, id)
+		// Status may be a 404 on unknown printer; also non-fatal when just unavailable.
+		if errors.Is(err, api.ErrNotFound) {
+			status = nil
+			err = nil
+		}
 		return
 	})
 	g.Go(func() (err error) {
@@ -51,6 +62,11 @@ func (h *PageHandler) PrinterDetailWithID(w http.ResponseWriter, r *http.Request
 	})
 	g.Go(func() (err error) {
 		queue, err = h.client.GetPrinterQueue(ctx, id)
+		// Queue absent is non-fatal.
+		if errors.Is(err, api.ErrNotFound) {
+			queue = nil
+			err = nil
+		}
 		return
 	})
 
@@ -63,9 +79,16 @@ func (h *PageHandler) PrinterDetailWithID(w http.ResponseWriter, r *http.Request
 		return
 	}
 
+	// If the printer detail itself was not found, return 404.
+	if printer == nil {
+		h.renderError(w, r, http.StatusNotFound, "Not Found", "printer not found: "+id)
+		return
+	}
+
 	h.renderPage(w, r, "printer", PrinterDetailData{
 		TemplateData: TemplateData{Version: h.version, ActiveNav: "dashboard"},
 		PrinterID:    id,
+		Printer:      printer,
 		Status:       status,
 		Tape:         tape,
 		Queue:        queue,
diff --git a/frontend/internal/handlers/printer_test.go b/frontend/internal/handlers/printer_test.go
index 87aa2e7..2a2630c 100644
--- a/frontend/internal/handlers/printer_test.go
+++ b/frontend/internal/handlers/printer_test.go
@@ -19,6 +19,12 @@ func printerDetailBackend(t *testing.T, id string) *httptest.Server {
 	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("Content-Type", "application/json")
 		switch r.URL.Path {
+		case "/api/printers/" + id:
+			json.NewEncoder(w).Encode(map[string]any{
+				"id": id, "name": "PT-P750W", "model": "pt_series", "backend": "tcp",
+				"connection": map[string]any{"host": "198.51.100.10", "port": 9100},
+				"enabled":    true, "paused": false, "created_at": now, "updated_at": now,
+			})
 		case "/api/printers/" + id + "/status":
 			json.NewEncoder(w).Encode(map[string]any{"printer_id": id, "online": true, "tape_loaded": "12mm black/clear", "error_state": nil, "captured_at": now})
 		case "/api/printers/" + id + "/tape":
@@ -31,6 +37,50 @@ func printerDetailBackend(t *testing.T, id string) *httptest.Server {
 	}))
 }
 
+func TestPrinterDetailShowsMetadata(t *testing.T) {
+	// Regression for Bug 2 — the printer detail page had no metadata block.
+	// Verify the handler populates Printer in PrinterDetailData so the template
+	// can render model/host/enabled/paused/created/updated fields.
+	//
+	// Strengthened assertions (Round 2): verify specific metadata fields are
+	// surfaced in the rendered output, not just the container div.
+	t.Parallel()
+	backend := printerDetailBackend(t, testPrinterID)
+	defer backend.Close()
+	ph := handlers.NewPageHandlerFromURL(t, backend.URL)
+
+	req := httptest.NewRequest(http.MethodGet, "/printers/"+testPrinterID, nil)
+	req.Header.Set("HX-Request", "true")
+	w := httptest.NewRecorder()
+	ph.PrinterDetailWithID(w, req, testPrinterID)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("status %d, body: %s", w.Code, w.Body.String())
+	}
+	body := w.Body.String()
+
+	// Container div must be present.
+	if !strings.Contains(body, "printer-detail") {
+		t.Errorf("body missing 'printer-detail', got: %s", body)
+	}
+
+	// The stub template now renders data-model so we can verify the model field
+	// round-trips correctly from the backend JSON to the template.
+	if !strings.Contains(body, "pt_series") {
+		t.Errorf("body missing model 'pt_series', got: %s", body)
+	}
+
+	// Host:port must be rendered for a TCP-connected printer.
+	if !strings.Contains(body, "198.51.100.10:9100") {
+		t.Errorf("body missing host:port '198.51.100.10:9100', got: %s", body)
+	}
+
+	// The enabled flag must be surfaced as data-enabled attribute.
+	if !strings.Contains(body, "data-enabled=\"true\"") {
+		t.Errorf("body missing data-enabled=true, got: %s", body)
+	}
+}
+
 func TestPrinterDetailOK(t *testing.T) {
 	t.Parallel()
 	backend := printerDetailBackend(t, testPrinterID)
@@ -78,3 +128,59 @@ func TestPrinterDetailNotFound(t *testing.T) {
 		t.Errorf("status %d, want 404", w.Code)
 	}
 }
+
+// usbPrinterBackend serves printer metadata for a USB-connected printer
+// (connection map has only "interface", no "host"/"port").
+func usbPrinterBackend(t *testing.T, id string) *httptest.Server {
+	t.Helper()
+	now := time.Now().Format(time.RFC3339)
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		switch r.URL.Path {
+		case "/api/printers/" + id:
+			json.NewEncoder(w).Encode(map[string]any{
+				"id": id, "name": "QL-820NWB", "model": "ql_series", "backend": "usb",
+				"connection": map[string]any{"interface": "usb"},
+				"enabled":    true, "paused": false, "created_at": now, "updated_at": now,
+			})
+		case "/api/printers/" + id + "/status":
+			json.NewEncoder(w).Encode(map[string]any{"printer_id": id, "online": false, "tape_loaded": nil, "error_state": nil, "captured_at": now})
+		case "/api/printers/" + id + "/tape":
+			json.NewEncoder(w).Encode(map[string]any{"width_mm": 62})
+		case "/api/printers/" + id + "/queue":
+			json.NewEncoder(w).Encode([]any{})
+		default:
+			http.NotFound(w, r)
+		}
+	}))
+}
+
+// TestPrinterDetailUSBConnection verifies that the printer detail page renders
+// correctly for USB-connected printers (connection has "interface" but no
+// "host"/"port"). The template must not crash and must surface the interface
+// value instead of an empty host:port pair.
+func TestPrinterDetailUSBConnection(t *testing.T) {
+	t.Parallel()
+	const usbID = "dddddddd-0000-0000-0000-000000000004"
+	backend := usbPrinterBackend(t, usbID)
+	defer backend.Close()
+	ph := handlers.NewPageHandlerFromURL(t, backend.URL)
+
+	req := httptest.NewRequest(http.MethodGet, "/printers/"+usbID, nil)
+	req.Header.Set("HX-Request", "true")
+	w := httptest.NewRecorder()
+	ph.PrinterDetailWithID(w, req, usbID)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("USB printer status %d, body: %s", w.Code, w.Body.String())
+	}
+	body := w.Body.String()
+	// The stub template renders the interface value inside a usb-badge span.
+	if !strings.Contains(body, "usb-badge") {
+		t.Errorf("USB printer body missing usb-badge span, got: %s", body)
+	}
+	// Must NOT render an empty host:port pair (bug guard).
+	if strings.Contains(body, "host-port") {
+		t.Errorf("USB printer body must not contain host-port span, got: %s", body)
+	}
+}
diff --git a/frontend/web/templates/printer.html b/frontend/web/templates/printer.html
index 05968df..807e730 100644
--- a/frontend/web/templates/printer.html
+++ b/frontend/web/templates/printer.html
@@ -6,6 +6,26 @@
 <div id="printer-detail" hx-ext="sse" sse-connect="/api/events?printer_id={{.PrinterID}}">
   <div class="space-y-6">
 
+    {{if .Printer}}
+    <div class="rounded-lg border border-surface-border bg-surface-raised p-4">
+      <h2 class="font-medium text-content mb-2">Metadata</h2>
+      <dl class="grid grid-cols-2 gap-x-4 gap-y-1 text-sm">
+        <dt class="text-content-secondary">Name</dt>           <dd>{{.Printer.Name}}</dd>
+        <dt class="text-content-secondary">Model</dt>          <dd>{{.Printer.Model}}</dd>
+        <dt class="text-content-secondary">Backend</dt>        <dd>{{.Printer.Backend}}</dd>
+        {{if and (index .Printer.Connection "host") (index .Printer.Connection "port")}}
+        <dt class="text-content-secondary">Host</dt>           <dd>{{index .Printer.Connection "host"}}:{{index .Printer.Connection "port"}}</dd>
+        {{else if index .Printer.Connection "interface"}}
+        <dt class="text-content-secondary">Interface</dt>      <dd>{{index .Printer.Connection "interface"}}</dd>
+        {{end}}
+        <dt class="text-content-secondary">Enabled</dt>        <dd>{{if .Printer.Enabled}}yes{{else}}no{{end}}</dd>
+        <dt class="text-content-secondary">Paused</dt>         <dd>{{if .Printer.Paused}}yes{{else}}no{{end}}</dd>
+        <dt class="text-content-secondary">Created</dt>        <dd>{{.Printer.CreatedAt}}</dd>
+        <dt class="text-content-secondary">Updated</dt>        <dd>{{.Printer.UpdatedAt}}</dd>
+      </dl>
+    </div>
+    {{end}}
+
     <div id="printer-status-panel"
          sse-swap="printer.status"
          hx-swap="innerHTML"