diff --git a/app/components/llm_connections/delete_api_key_dialog_component.rb b/app/components/llm_connections/delete_api_key_dialog_component.rb
index aaf46b1574ae..4e0f49fc9805 100644
--- a/app/components/llm_connections/delete_api_key_dialog_component.rb
+++ b/app/components/llm_connections/delete_api_key_dialog_component.rb
@@ -31,8 +31,7 @@
 module LlmConnections
   # Confirms removing the stored API key.
   #
-  # No confirmation checkbox: the key itself can simply be pasted again. The
-  # dialog exists for what is *not* recoverable.
+  # No confirmation checkbox: the key itself can simply be pasted again.
   class DeleteApiKeyDialogComponent < ApplicationComponent
     include OpTurbo::Streamable
     include OpPrimer::ComponentHelpers
diff --git a/app/components/llm_connections/disconnect_dialog_component.html.erb b/app/components/llm_connections/disconnect_dialog_component.html.erb
index b7aa5a26855b..bbcda28dc1fa 100644
--- a/app/components/llm_connections/disconnect_dialog_component.html.erb
+++ b/app/components/llm_connections/disconnect_dialog_component.html.erb
@@ -20,7 +20,8 @@
           content_tag(:ul) do
             safe_join(
               [
-                content_tag(:li, t("admin.llm_connections.disconnect.keeps_settings"))
+                content_tag(:li, t("admin.llm_connections.disconnect.keeps_settings")),
+                content_tag(:li, t("admin.llm_connections.disconnect.keeps_models"))
               ].compact
             )
           end
diff --git a/app/controllers/admin/llm_connections_controller.rb b/app/controllers/admin/llm_connections_controller.rb
index 01f8a2b09fed..f98f48338ff1 100644
--- a/app/controllers/admin/llm_connections_controller.rb
+++ b/app/controllers/admin/llm_connections_controller.rb
@@ -87,8 +87,19 @@ def require_feature
       render_404 unless OpenProject::FeatureDecisions.llm_connection_active?
     end
 
+    # A connection can be perfectly usable without offering a model list, so the
+    # save succeeds either way; the administrator is told what to do next rather
+    # than being left with an empty table and no explanation.
     def redirect_after_save
-      redirect_with_notice(@connection.llm_features_enabled ? t(".success") : t(".disabled"))
+      return redirect_with_notice(t(".disabled")) unless @connection.llm_features_enabled
+
+      if @connection.reload.models.none?
+        flash[:warning] = t(".no_models")
+      else
+        flash[:notice] = t(".success")
+      end
+
+      redirect_to llm_connection_path, status: :see_other
     end
 
     def render_form_with_errors
diff --git a/app/models/llm_capability_verdict.rb b/app/models/llm_capability_verdict.rb
new file mode 100644
index 000000000000..b6fe7d1e73df
--- /dev/null
+++ b/app/models/llm_capability_verdict.rb
@@ -0,0 +1,70 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+# What we know about one capability of one model on one server.
+#
+# Three states rather than a boolean, because the honest answer is very often
+# "we cannot tell": the OpenAI model list carries no capability information at
+# all, and only some servers offer a non-standard endpoint that does.
+#
+# The rule the rest of the system depends on: only :unsupported blocks. An
+# :unknown verdict warns and lets the administrator proceed, because refusing
+# on "we could not tell" would make most self-hosted servers unusable.
+class LlmCapabilityVerdict < ApplicationRecord
+  belongs_to :llm_connection
+
+  enum :state, { supported: "supported", unsupported: "unsupported", unknown: "unknown" }, validate: true
+
+  # Where the verdict came from. Orthogonal to the state, so that an
+  # administrator's assertion can be shown as such without adding a fourth state
+  # that every caller would have to handle.
+  enum :source,
+       { metadata: "metadata", probe: "probe", admin: "admin", observed: "observed" },
+       prefix: true,
+       validate: true
+
+  validates :model_id, presence: true
+  validates :capability, presence: true, uniqueness: { scope: %i[llm_connection_id model_id] }
+
+  scope :for_model, ->(model_id) { where(model_id:) }
+  scope :for_capability, ->(capability) { where(capability: capability.to_s) }
+
+  # An administrator's assertion survives re-detection: they know something about
+  # their deployment that we could not determine.
+  scope :sticky, -> { where(source: "admin") }
+
+  def blocking?
+    unsupported?
+  end
+
+  def dimensions
+    detail["dimensions"]
+  end
+end
diff --git a/app/models/llm_connection.rb b/app/models/llm_connection.rb
index 8080d7beaa3b..9912b52d0de0 100644
--- a/app/models/llm_connection.rb
+++ b/app/models/llm_connection.rb
@@ -47,6 +47,11 @@ class LlmConnection < ApplicationRecord
 
   scope :active, -> { where(active: true) }
 
+  has_many :models, class_name: "LlmModel", dependent: :delete_all
+
+  belongs_to :default_chat_model, class_name: "LlmModel", optional: true
+  belongs_to :default_embedding_model, class_name: "LlmModel", optional: true
+  has_many :capability_verdicts, class_name: "LlmCapabilityVerdict", dependent: :delete_all
   validates :base_url, presence: true
   validate :single_active_connection, if: :active?
 
@@ -76,6 +81,28 @@ def configured?
     base_url.present?
   end
 
+  # Every model that can be addressed today: discovered and still offered, plus
+  # anything an administrator entered by hand.
+  #
+  # Deliberately includes models an administrator has deactivated. This is what
+  # Llm::Runtime resolves against, and hiding a model from the pickers must not
+  # break a feature that is already bound to it.
+  def available_model_ids
+    models.active.by_identifier.pluck(:external_id)
+  end
+
+  # Identifies the deployment the models were fetched from. Recorded by
+  # LlmConnections::SyncModelsService as +connection_fingerprint+.
+  def settings_fingerprint
+    Digest::SHA256.hexdigest("#{api_format}\0#{base_url}\0#{api_key}")
+  end
+
+  # The stored models were fetched from another deployment than the one
+  # configured now, so the list may no longer describe what the server offers.
+  def models_stale?
+    connection_fingerprint.present? && connection_fingerprint != settings_fingerprint
+  end
+
   def server_flavour
     options["server_flavour"].presence&.to_sym
   end
diff --git a/app/models/llm_model.rb b/app/models/llm_model.rb
new file mode 100644
index 000000000000..dbec6362c8bb
--- /dev/null
+++ b/app/models/llm_model.rb
@@ -0,0 +1,84 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+# A model this connection can address.
+#
+# Rows come from two places: discovered from the server's model list, or entered
+# by an administrator. Both are addressed by +external_id+, which is whatever the
+# deployment calls the model -- provider-specific and not comparable across
+# vendors, which is why it is never used as a lookup key into a public catalogue.
+class LlmModel < ApplicationRecord
+  belongs_to :llm_connection
+
+  validates :external_id, presence: true, uniqueness: { scope: :llm_connection_id }
+
+  scope :active, -> { where(active: true) }
+  scope :discovered, -> { where(manual: false) }
+  scope :manual, -> { where(manual: true) }
+  scope :by_identifier, -> { order(:external_id) }
+
+  def name = display_name.presence || external_id
+
+  # Precedence: what an administrator set, then what the server reported (vLLM
+  # and SGLang publish the operator's actual --max-model-len), then what a
+  # registry believes about the model in general.
+  def context_window
+    raw_metadata["admin_context_window"] ||
+      raw_metadata["max_model_len"] ||
+      raw_metadata["context_window"]
+  end
+
+  def context_window_source
+    return :admin if raw_metadata["admin_context_window"].present?
+    return :server if raw_metadata["max_model_len"].present?
+    return :registry if raw_metadata["context_window"].present?
+
+    nil
+  end
+
+  # A model is an embedding model when its embeddings verdict says so, and a
+  # chat model otherwise. There is no third kind, and no model is both.
+  def embedding? = verdict_for(:embeddings)&.state == "supported"
+
+  def model_type = embedding? ? :embedding : :chat
+
+  def verdict_for(capability)
+    llm_connection.capability_verdicts
+                  .for_model(external_id)
+                  .for_capability(capability)
+                  .first
+  end
+
+  # Discovered models that the server stopped offering are deactivated rather
+  # than deleted, so a binding or verdict pointing at one still has something to
+  # name. Manual entries are never deactivated by a refresh: nothing confirms
+  # them, so nothing can un-confirm them either.
+  def withdrawn? = !active? && !manual?
+end
diff --git a/app/services/llm/capabilities.rb b/app/services/llm/capabilities.rb
new file mode 100644
index 000000000000..edd4a40727c8
--- /dev/null
+++ b/app/services/llm/capabilities.rb
@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+module Llm
+  # The capabilities a model may have, and how to read the published ones.
+  module Capabilities
+    ALL = %i[embeddings function_calling structured_output vision reasoning].freeze
+
+    # Capabilities a chat model can be asked about. +embeddings+ is deliberately
+    # absent: it is a different kind of model, not a feature of a chat one.
+    CHAT = (ALL - %i[embeddings]).freeze
+    EMBEDDING = %i[embeddings].freeze
+
+    module_function
+
+    # What a public registry says about this model id.
+    #
+    # Advisory only. The registry describes a model as some vendor deploys it,
+    # which is not the same as this deployment: the same weights are catalogued
+    # with contradictory capability flags and context windows an order of
+    # magnitude apart across providers. Verdicts derived from it are therefore
+    # recorded with source "metadata", and an administrator can overrule them.
+    #
+    # @return [Hash{Symbol => Symbol}, nil] capability => :supported / :unsupported,
+    #   or nil when the registry does not know the model -- the normal case for a
+    #   self-hosted server.
+    def published_for(model_id)
+      info = RubyLLM.models.find(model_id)
+
+      { states: states_from(info), context_window: info.context_window, display_name: info.name }
+    rescue RubyLLM::ModelNotFoundError
+      nil
+    rescue StandardError => e
+      # Registry lookup is an enrichment; it must never break a model sync.
+      Rails.logger.info { "LLM capability lookup for #{model_id} failed: #{e.class} #{e.message}" }
+      nil
+    end
+
+    def states_from(info)
+      embedding = info.type.to_s == "embedding"
+      published = Array(info.capabilities).map(&:to_sym)
+      relevant = embedding ? EMBEDDING : CHAT
+      # An entry that lists no capability at all says nothing about the model,
+      # which is not the same as saying it can do nothing.
+      unpublished = published.empty? ? :unknown : :unsupported
+
+      states = relevant.index_with { |capability| published.include?(capability) ? :supported : unpublished }
+      states.merge(embeddings: embedding ? :supported : :unsupported)
+    end
+
+    def label(capability)
+      I18n.t("llm.capabilities.#{capability}.label")
+    end
+  end
+end
diff --git a/app/services/llm_connections/enrich_capabilities_service.rb b/app/services/llm_connections/enrich_capabilities_service.rb
new file mode 100644
index 000000000000..e5d53976d4b0
--- /dev/null
+++ b/app/services/llm_connections/enrich_capabilities_service.rb
@@ -0,0 +1,85 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+module LlmConnections
+  # Fills in what a public registry publishes about the models a connection offers.
+  #
+  # This is the "the provider tells us" path. A hosted provider's model ids are
+  # catalogued, so capabilities arrive without asking the server anything. A
+  # self-hosted deployment naming its model "default" or "my-finetune-v3" is not
+  # catalogued, nothing is filled in, and the administrator enters capabilities
+  # by hand instead.
+  #
+  # An administrator's assertion is never overwritten: they know things about
+  # their deployment that no registry can.
+  class EnrichCapabilitiesService
+    def initialize(connection)
+      @connection = connection
+    end
+
+    def call
+      connection.models.active.find_each { |llm_model| enrich(llm_model) }
+
+      ServiceResult.success(result: connection)
+    end
+
+    private
+
+    attr_reader :connection
+
+    def enrich(llm_model)
+      published = Llm::Capabilities.published_for(llm_model.external_id)
+      return if published.nil?
+
+      apply_metadata(llm_model, published)
+      published[:states].each { |capability, state| record(llm_model.external_id, capability, state) }
+    end
+
+    def apply_metadata(llm_model, published)
+      attributes = {}
+      attributes[:display_name] = published[:display_name] if llm_model.display_name.blank?
+
+      if published[:context_window].present? && llm_model.raw_metadata["max_model_len"].blank?
+        attributes[:raw_metadata] = llm_model.raw_metadata.merge("context_window" => published[:context_window])
+      end
+
+      llm_model.update!(attributes) if attributes.any?
+    end
+
+    def record(model_id, capability, state)
+      verdict = connection.capability_verdicts.find_or_initialize_by(model_id:, capability: capability.to_s)
+      # Anything an administrator or a probe established beats a published claim:
+      # both looked at this deployment, the registry did not.
+      return if verdict.persisted? && verdict.source.in?(%w[admin probe])
+
+      verdict.update!(state: state.to_s, source: "metadata", checked_at: Time.current)
+    end
+  end
+end
diff --git a/app/services/llm_connections/sync_models_service.rb b/app/services/llm_connections/sync_models_service.rb
new file mode 100644
index 000000000000..9301d7cb4cfe
--- /dev/null
+++ b/app/services/llm_connections/sync_models_service.rb
@@ -0,0 +1,154 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+module LlmConnections
+  # Refreshes the model list from the remote server.
+  #
+  # Kept separate from the contract probe so the same path serves the "Refresh
+  # models" button, the update service and the environment seeder.
+  class SyncModelsService
+    def initialize(connection)
+      @connection = connection
+    end
+
+    def call
+      # Before the fetch, so that a deployment change invalidates the old state
+      # even when the new server refuses the model list: keeping the previous
+      # deployment's models and verdicts under new credentials would be wrong.
+      invalidate_a_different_deployment
+
+      store(adapter.models)
+
+      ServiceResult.success(result: connection)
+    rescue Llm::Client::Error => e
+      Rails.logger.info { "LLM model sync for #{connection.base_url} failed: #{e.class} #{e.message}" }
+      ServiceResult.failure(errors: e.message)
+    end
+
+    private
+
+    attr_reader :connection
+
+    def adapter
+      @adapter ||= Llm::Adapters.for(connection)
+    end
+
+    def store(cards)
+      ActiveRecord::Base.transaction do
+        connection.update!(connection_attributes)
+        upsert(cards)
+        withdraw_models_absent_from(cards)
+        discard_verdicts_for_vanished_models
+      end
+
+      EnrichCapabilitiesService.new(connection).call
+    end
+
+    def connection_attributes
+      now = Time.current
+
+      {
+        catalogue_fetched_at: now,
+        last_connected_at: now,
+        connection_fingerprint: fingerprint,
+        options: connection.options.merge("server_flavour" => adapter.server_flavour)
+      }
+    end
+
+    def fingerprint
+      @fingerprint ||= connection.settings_fingerprint
+    end
+
+    def upsert(cards)
+      now = Time.current
+
+      cards.each do |card|
+        model = connection.models.find_or_initialize_by(external_id: card.fetch(:id))
+        model.update!(display_name: card[:display_name].presence || model.display_name,
+                      raw_metadata: merged_metadata(model, card),
+                      last_seen_at: now,
+                      active: true)
+      end
+    end
+
+    # Deactivated rather than deleted, so a binding or verdict pointing at one
+    # still has something to name. Manual entries are left alone: the server was
+    # never the thing that confirmed them.
+    # where.not against an empty id list matches nothing, so an empty catalogue
+    # needs its own branch to withdraw everything discovered.
+    def withdraw_models_absent_from(cards)
+      ids = cards.map { |card| card.fetch(:id) }
+      scope = connection.models.discovered
+      scope = scope.where.not(external_id: ids) if ids.any?
+
+      scope.update_all(active: false)
+    end
+
+    # A changed base URL or key means a different deployment, so what the
+    # registry and the probes established about the old one is void. What an
+    # administrator asserted is theirs and survives, as it does on a refresh.
+    def invalidate_a_different_deployment
+      return if connection.connection_fingerprint.blank?
+      return if connection.connection_fingerprint == fingerprint
+
+      forget_the_previous_deployment
+    end
+
+    # Only a successful fetch records the fingerprint (see
+    # +connection_attributes+), so a failed refresh leaves the list stale.
+    def forget_the_previous_deployment
+      ActiveRecord::Base.transaction do
+        connection.capability_verdicts.where.not(source: "admin").delete_all
+        connection.models.discovered.update_all(active: false)
+      end
+    end
+
+    # The server names the model, but only when it says so: the administrator's
+    # display name and context-window override are theirs, and a routine refresh
+    # must not silently discard them.
+    def merged_metadata(model, card)
+      raw = card.fetch(:raw, {})
+      admin_window = model.raw_metadata["admin_context_window"]
+
+      admin_window ? raw.merge("admin_context_window" => admin_window) : raw
+    end
+
+    # Same deployment, but a model is gone. Its verdict is meaningless now,
+    # except an administrator's assertion: an operator restarting a server must
+    # not silently lose one.
+    def discard_verdicts_for_vanished_models
+      known = connection.available_model_ids
+      scope = connection.capability_verdicts.where.not(source: "admin")
+      scope = scope.where.not(model_id: known) if known.any?
+
+      scope.delete_all
+    end
+  end
+end
diff --git a/app/services/llm_connections/update_service.rb b/app/services/llm_connections/update_service.rb
index a8e8e1982474..2b77bcb2f979 100644
--- a/app/services/llm_connections/update_service.rb
+++ b/app/services/llm_connections/update_service.rb
@@ -32,10 +32,25 @@ module LlmConnections
   class UpdateService < BaseServices::Update
     private
 
-    def after_perform(call)
-      Setting.llm_features_enabled = model.llm_features_enabled if call.success?
+    # The contract has already proven the server reachable when the credentials
+    # changed, so refreshing the catalogue here cannot be the thing that fails
+    # the save. A sync failure is therefore logged, not surfaced.
+    def after_perform(service_call)
+      super.tap do
+        next unless service_call.success?
 
-      call
+        Setting.llm_features_enabled = model.llm_features_enabled
+        next unless initial_fill?(service_call.result)
+
+        SyncModelsService.new(service_call.result).call
+      end
+    end
+
+    # The only automatic refresh: nothing is stored yet, so nothing an
+    # administrator curated can be lost. Every later refresh is asked for.
+    def initial_fill?(connection)
+      connection.saved_changes.keys.intersect?(LlmServerValidator::CONNECTION_ATTRIBUTES) &&
+        connection.models.none?
     end
   end
 end
diff --git a/app/workers/llm/sync_models_job.rb b/app/workers/llm/sync_models_job.rb
new file mode 100644
index 000000000000..9cb300e24624
--- /dev/null
+++ b/app/workers/llm/sync_models_job.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+module Llm
+  # Refreshes the cached model catalogue out of band.
+  #
+  # Used by the environment seeder, which must not block on -- or fail because of
+  # -- an LLM server that has not finished starting.
+  class SyncModelsJob < ApplicationJob
+    def perform
+      LlmConnection.find_each do |connection|
+        LlmConnections::SyncModelsService.new(connection).call
+      end
+    end
+  end
+end
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 0d09a862ed07..34d0c0c8bf8b 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -201,6 +201,10 @@ en:
         onthefly: "Automatic user creation"
         port: "Port"
         tls_certificate_string: "LDAP server SSL certificate"
+      llm_capability_verdict:
+        capability: "Capability"
+        model_id: "Model"
+        state: "State"
       llm_connection:
         api_format: "API format"
         api_key: "API key"
@@ -208,6 +212,10 @@ en:
         # ActiveRecord::Base.human_attribute_name strips the _id suffix, so these
         # keys deliberately do not carry it (see lib/open_project/patches/active_record_i18n.rb).
         llm_features_enabled: "Enable LLMs for this instance"
+      llm_model:
+        display_name: "Display name"
+        # human_attribute_name strips the _id suffix, so the key omits it.
+        external: "Model name"
       mcp_configuration:
         description: Description
         enabled: Enabled
@@ -1708,6 +1716,7 @@ en:
       disconnect:
         description: "OpenProject will stop using the LLM server. AI features will be unavailable until you connect again."
         heading: "Disconnect from the LLM server?"
+        keeps_models: "The model list, including any models you added manually, is kept."
         keeps_settings: "The endpoint and API format are kept. Only the stored API key is removed."
         menu_label: "Disconnect"
         success: "OpenProject has disconnected from the LLM server."
@@ -1728,6 +1737,7 @@ en:
         description: "Connect OpenProject to an LLM server so that AI features can use it."
       update:
         disabled: "Saved. LLM features are switched off for this instance."
+        no_models: "Saved, but no models are stored yet. Either the server offers no model list, or the endpoint is missing its API version segment (for example /v1)."
         success: "Successfully connected to the LLM server."
     mcp_configurations:
       index:
diff --git a/db/migrate/20260811140000_create_llm_capability_verdicts.rb b/db/migrate/20260811140000_create_llm_capability_verdicts.rb
new file mode 100644
index 000000000000..1e94a71fa5e0
--- /dev/null
+++ b/db/migrate/20260811140000_create_llm_capability_verdicts.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+class CreateLlmCapabilityVerdicts < ActiveRecord::Migration[8.1]
+  def change
+    create_table :llm_capability_verdicts do |t|
+      t.references :llm_connection, null: false, foreign_key: true
+      # A plain string, not a foreign key: the catalogue is a cache of a remote
+      # list, and a model may vanish from it without invalidating what we learned.
+      t.string :model_id, null: false
+      t.string :capability, null: false
+      t.string :state, null: false
+      t.string :source, null: false
+      t.jsonb :detail, null: false, default: {}
+      t.datetime :checked_at, null: false
+
+      t.timestamps null: false
+    end
+
+    add_index :llm_capability_verdicts,
+              %i[llm_connection_id model_id capability],
+              unique: true,
+              name: "index_llm_capability_verdicts_on_connection_model_capability"
+  end
+end
diff --git a/db/migrate/20260812090000_create_llm_models.rb b/db/migrate/20260812090000_create_llm_models.rb
new file mode 100644
index 000000000000..2552d109b7f7
--- /dev/null
+++ b/db/migrate/20260812090000_create_llm_models.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+class CreateLlmModels < ActiveRecord::Migration[8.1]
+  def change
+    create_table :llm_models do |t|
+      t.references :llm_connection, null: false, foreign_key: true
+      # Whatever this deployment calls the model. Provider-specific: Scaleway
+      # serves "qwen3.6-35b-a3b" for weights another catalogue lists as
+      # "Qwen/Qwen3.6-35B-A3B".
+      t.string :external_id, null: false
+      t.string :display_name
+      t.boolean :active, null: false, default: true
+      # Entered by an administrator rather than discovered. Survives a refresh
+      # that cannot see it, which is what makes a server offering
+      # /v1/chat/completions but no /v1/models usable.
+      t.boolean :manual, null: false, default: false
+      t.datetime :last_seen_at
+      t.jsonb :raw_metadata, null: false, default: {}
+
+      t.timestamps null: false
+    end
+
+    add_index :llm_models, %i[llm_connection_id external_id], unique: true
+
+    # The catalogue is superseded by the table above, and a model the server
+    # stops reporting keeps its row here, so a default can be a reference rather
+    # than an identifier that nothing resolves. Clearing it on delete is what the
+    # administrator is warned about before removing a model.
+    change_table :llm_connections, bulk: true do |t|
+      t.remove :catalogue, type: :jsonb, null: false, default: {}
+      t.remove :default_chat_model_id, type: :string
+      t.remove :default_embedding_model_id, type: :string
+      t.references :default_chat_model, null: true,
+                                        foreign_key: { to_table: :llm_models, on_delete: :nullify }
+      t.references :default_embedding_model, null: true,
+                                             foreign_key: { to_table: :llm_models, on_delete: :nullify }
+    end
+  end
+end
diff --git a/spec/factories/llm_connection_factory.rb b/spec/factories/llm_connection_factory.rb
index 4dd95263d50d..c18f1b837c1e 100644
--- a/spec/factories/llm_connection_factory.rb
+++ b/spec/factories/llm_connection_factory.rb
@@ -33,5 +33,16 @@
     sequence(:identifier) { |n| n == 1 ? LlmConnection::DEFAULT_IDENTIFIER : "connection-#{n}" }
     base_url { "https://example.com/v1" }
     api_key { "sk-test-key" }
+    trait :with_models do
+      catalogue_fetched_at { Time.current }
+      last_connected_at { Time.current }
+
+      after(:create) do |connection|
+        create(:llm_model, llm_connection: connection, external_id: "qwen3.6-27b",
+                           raw_metadata: { "owned_by" => "vllm", "max_model_len" => 262_144 })
+        create(:llm_model, llm_connection: connection, external_id: "bge-m3",
+                           raw_metadata: { "owned_by" => "vllm", "max_model_len" => 8_192 })
+      end
+    end
   end
 end
diff --git a/spec/factories/llm_model_factory.rb b/spec/factories/llm_model_factory.rb
new file mode 100644
index 000000000000..59527ef65278
--- /dev/null
+++ b/spec/factories/llm_model_factory.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+FactoryBot.define do
+  factory :llm_model do
+    llm_connection
+    sequence(:external_id) { |n| "model-#{n}" }
+    active { true }
+    manual { false }
+    last_seen_at { Time.current }
+
+    trait :manual do
+      manual { true }
+      last_seen_at { nil }
+    end
+
+    trait :withdrawn do
+      active { false }
+    end
+
+    # Still offered by the server; hidden by an administrator.
+    trait :deactivated do
+      deactivated_at { Time.current }
+    end
+  end
+end
diff --git a/spec/models/llm_connection_spec.rb b/spec/models/llm_connection_spec.rb
index eec473a46473..26a4b4251922 100644
--- a/spec/models/llm_connection_spec.rb
+++ b/spec/models/llm_connection_spec.rb
@@ -93,4 +93,41 @@
       expect(described_class.active_connection).to eq(connection)
     end
   end
+
+  describe "#settings_fingerprint" do
+    subject(:connection) { build(:llm_connection, base_url: "https://example.com/v1", api_key: "sk-test") }
+
+    it "changes with the API format" do
+      expect { connection.api_format = "anthropic" }.to change(connection, :settings_fingerprint)
+    end
+
+    it "changes with the host URL" do
+      expect { connection.base_url = "https://elsewhere.example/v1" }.to change(connection, :settings_fingerprint)
+    end
+
+    it "changes with the API key" do
+      expect { connection.api_key = "sk-rotated" }.to change(connection, :settings_fingerprint)
+    end
+  end
+
+  describe "#models_stale?" do
+    subject(:connection) { create(:llm_connection, base_url: "https://example.com/v1", api_key: "sk-test") }
+
+    it "is false while no model list has been fetched" do
+      expect(connection).not_to be_models_stale
+    end
+
+    it "is false while the settings still match the fetched list" do
+      connection.update!(connection_fingerprint: connection.settings_fingerprint)
+
+      expect(connection).not_to be_models_stale
+    end
+
+    it "is true once a connection setting changed" do
+      connection.update!(connection_fingerprint: connection.settings_fingerprint)
+      connection.update!(api_key: "sk-rotated")
+
+      expect(connection).to be_models_stale
+    end
+  end
 end
diff --git a/spec/models/llm_model_spec.rb b/spec/models/llm_model_spec.rb
new file mode 100644
index 000000000000..b9143bef6ace
--- /dev/null
+++ b/spec/models/llm_model_spec.rb
@@ -0,0 +1,58 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+require "spec_helper"
+
+RSpec.describe LlmModel do
+  let(:connection) { create(:llm_connection) }
+  let(:llm_model) { create(:llm_model, llm_connection: connection, external_id: "bge-m3") }
+
+  describe "#model_type" do
+    it "is chat while nothing says the model embeds" do
+      expect(llm_model).not_to be_embedding
+      expect(llm_model.model_type).to eq(:chat)
+    end
+
+    it "is embedding once the embeddings verdict says so" do
+      connection.capability_verdicts.create!(model_id: llm_model.external_id, capability: "embeddings",
+                                             state: "supported", source: "admin", checked_at: Time.current)
+
+      expect(llm_model).to be_embedding
+      expect(llm_model.model_type).to eq(:embedding)
+    end
+
+    it "is chat when the embeddings verdict is unknown" do
+      connection.capability_verdicts.create!(model_id: llm_model.external_id, capability: "embeddings",
+                                             state: "unknown", source: "metadata", checked_at: Time.current)
+
+      expect(llm_model.model_type).to eq(:chat)
+    end
+  end
+end
diff --git a/spec/requests/admin/llm_connections_spec.rb b/spec/requests/admin/llm_connections_spec.rb
index 2263f4ffa131..0a02eec4d73a 100644
--- a/spec/requests/admin/llm_connections_spec.rb
+++ b/spec/requests/admin/llm_connections_spec.rb
@@ -117,12 +117,55 @@
         expect(connection.api_key).to eq("sk-test")
       end
 
+      it "fills the catalogue once when none is stored" do
+        patch llm_connection_path, params: { llm_connection: { base_url:, api_key: "sk-test" } }
+
+        expect(LlmConnection.first.available_model_ids).to contain_exactly("qwen3.6-27b", "bge-m3")
+      end
+
       it "confirms the connection once LLMs are switched on" do
         patch llm_connection_path,
               params: { llm_connection: { llm_features_enabled: "1", base_url:, api_key: "sk-test" } }
 
         expect(flash[:notice]).to eq(I18n.t("admin.llm_connections.update.success"))
       end
+
+      context "when models are already stored" do
+        let!(:connection) { create(:llm_connection, :with_models, base_url:, api_key: "sk-test") }
+
+        before do
+          connection.update!(connection_fingerprint: connection.settings_fingerprint)
+          connection.capability_verdicts.create!(model_id: "qwen3.6-27b", capability: "embeddings",
+                                                 state: "supported", source: "admin", checked_at: Time.current)
+        end
+
+        it "leaves the stored catalogue alone when the host URL changes" do
+          elsewhere = "https://elsewhere.example/v1"
+          mock_llm_models_response(elsewhere, models: [{ id: "llama4-8b", object: "model", owned_by: "vllm" }])
+
+          patch llm_connection_path, params: { llm_connection: { base_url: elsewhere } }
+
+          connection.reload
+          expect(connection.available_model_ids).to contain_exactly("qwen3.6-27b", "bge-m3")
+          expect(connection.capability_verdicts.pluck(:source)).to eq(["admin"])
+          expect(connection).to be_models_stale
+        end
+      end
+    end
+
+    # The case that matters for OpenProject's own gateway: chat completions are
+    # routed, the model list is not.
+    context "with a server that exposes no model list" do
+      let!(:models_request) { mock_llm_models_response(base_url, response_code: 404) }
+
+      it "still saves the connection and says models must be added by hand" do
+        patch llm_connection_path,
+              params: { llm_connection: { llm_features_enabled: "1", base_url:, api_key: "sk-test" } }
+
+        expect(response).to have_http_status(:see_other)
+        expect(LlmConnection.first.base_url).to eq(base_url)
+        expect(flash[:warning]).to be_present
+      end
     end
 
     context "when the administrator switches LLMs off" do
@@ -226,9 +269,25 @@
     end
   end
 
+  describe "GET /admin/llm_connection/delete_api_key_dialog" do
+    let!(:connection) { create(:llm_connection, base_url: "https://example.com/v1", api_key: "sk-test") }
+
+    before { login_as admin }
+
+    it "offers the confirmation" do
+      # Requested by the async-dialog Stimulus controller, which asks for a
+      # turbo stream rather than HTML.
+      get delete_api_key_dialog_llm_connection_path,
+          headers: { "Accept" => "text/vnd.turbo-stream.html" }
+
+      expect(response).to have_http_status(:ok)
+      expect(response.body).to include("Remove the stored API key?")
+    end
+  end
+
   describe "disconnecting" do
     let!(:connection) do
-      create(:llm_connection,
+      create(:llm_connection, :with_models,
              base_url: "https://example.com/v1", api_key: "sk-test")
     end
 
@@ -253,6 +312,7 @@
       expect(connection.api_key).to be_blank
       expect(Setting.llm_features_enabled?).to be(false)
       expect(connection.base_url).to eq("https://example.com/v1")
+      expect(connection.models.count).to eq(2)
     end
 
     it "is refused to a non-admin" do
diff --git a/spec/services/llm/capabilities_spec.rb b/spec/services/llm/capabilities_spec.rb
new file mode 100644
index 000000000000..73c3b075655a
--- /dev/null
+++ b/spec/services/llm/capabilities_spec.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+require "spec_helper"
+
+RSpec.describe Llm::Capabilities do
+  describe ".states_from" do
+    subject(:states) { described_class.states_from(info) }
+
+    context "with an embedding entry" do
+      let(:info) { instance_double(RubyLLM::Model::Info, type: "embedding", capabilities: []) }
+
+      it "reports embeddings only" do
+        expect(states).to eq(embeddings: :supported)
+      end
+    end
+
+    context "with a chat entry listing its capabilities" do
+      let(:info) { instance_double(RubyLLM::Model::Info, type: "chat", capabilities: %w[function_calling vision]) }
+
+      it "reports the listed ones as supported and the rest as unsupported" do
+        expect(states).to eq(embeddings: :unsupported,
+                             function_calling: :supported,
+                             structured_output: :unsupported,
+                             vision: :supported,
+                             reasoning: :unsupported)
+      end
+    end
+
+    context "with a chat entry listing no capability at all" do
+      let(:info) { instance_double(RubyLLM::Model::Info, type: "chat", capabilities: []) }
+
+      it "leaves the chat capabilities unknown rather than denying them" do
+        expect(states).to eq(embeddings: :unsupported,
+                             function_calling: :unknown,
+                             structured_output: :unknown,
+                             vision: :unknown,
+                             reasoning: :unknown)
+      end
+    end
+  end
+end
diff --git a/spec/services/llm_connections/sync_models_service_spec.rb b/spec/services/llm_connections/sync_models_service_spec.rb
new file mode 100644
index 000000000000..f39d3ca53116
--- /dev/null
+++ b/spec/services/llm_connections/sync_models_service_spec.rb
@@ -0,0 +1,129 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+require "spec_helper"
+
+RSpec.describe LlmConnections::SyncModelsService, :llm_server_helpers, :webmock do
+  subject(:service) { described_class.new(connection) }
+
+  let(:base_url) { "https://example.com/v1" }
+  let(:connection) { create(:llm_connection, :with_models, base_url:, api_key: "sk-test") }
+
+  before { mock_llm_models_response(base_url) }
+
+  describe "switching to a different deployment" do
+    before do
+      connection.capability_verdicts.create!(model_id: "qwen3.6-27b", capability: "embeddings",
+                                             state: "supported", source: "admin", checked_at: Time.current)
+      connection.capability_verdicts.create!(model_id: "qwen3.6-27b", capability: "vision",
+                                             state: "unsupported", source: "metadata", checked_at: Time.current)
+      connection.update_columns(base_url: "https://elsewhere.example/v1",
+                                connection_fingerprint: "the-previous-deployment")
+    end
+
+    it "invalidates the old models and verdicts even when the new server offers no list" do
+      mock_llm_models_response("https://elsewhere.example/v1", response_code: 404)
+
+      result = service.call
+
+      expect(result).to be_failure
+      expect(connection.capability_verdicts.pluck(:capability, :source)).to eq([%w[embeddings admin]])
+      expect(connection.models.active).to be_empty
+    end
+
+    it "keeps warning about a stale list when the new server refuses it" do
+      mock_llm_models_response("https://elsewhere.example/v1", response_code: 404)
+
+      expect(service.call).to be_failure
+      expect(connection.reload).to be_models_stale
+    end
+
+    it "keeps administrator assertions and re-activates what the new server reports" do
+      mock_llm_models_response("https://elsewhere.example/v1")
+
+      described_class.new(connection).call
+
+      expect(connection.capability_verdicts.where(source: "admin").pluck(:capability)).to eq(["embeddings"])
+      expect(connection.models.active.pluck(:external_id)).to contain_exactly("qwen3.6-27b", "bge-m3")
+    end
+  end
+
+  describe "refreshing the same deployment" do
+    before { service.call }
+
+    it "keeps an administrator's context window override across refreshes" do
+      llm_model = connection.models.find_by(external_id: "qwen3.6-27b")
+      llm_model.update!(raw_metadata: llm_model.raw_metadata.merge("admin_context_window" => 4096))
+
+      described_class.new(connection).call
+
+      expect(llm_model.reload.context_window).to eq(4096)
+    end
+
+    it "keeps an administrator's display name when the server reports none" do
+      llm_model = connection.models.find_by(external_id: "qwen3.6-27b")
+      llm_model.update!(display_name: "The house model")
+
+      described_class.new(connection).call
+
+      expect(llm_model.reload.display_name).to eq("The house model")
+    end
+
+    # Only the registry-backed adapters report a name; a server speaking the
+    # OpenAI API lists ids and nothing else.
+    it "adopts the display name the adapter reports" do
+      llm_model = connection.models.find_by(external_id: "qwen3.6-27b")
+      llm_model.update!(display_name: "The house model")
+      allow(Llm::Adapters).to receive(:for).and_return(
+        instance_double(Llm::Adapters::RegistryBacked,
+                        models: [{ id: "qwen3.6-27b", display_name: "Qwen 3.6 27B", raw: {} }],
+                        server_flavour: "anthropic")
+      )
+
+      described_class.new(connection).call
+
+      expect(llm_model.reload.display_name).to eq("Qwen 3.6 27B")
+    end
+
+    it "drops every non-admin verdict when the catalogue comes back empty" do
+      connection.capability_verdicts.create!(model_id: "qwen3.6-27b", capability: "embeddings",
+                                             state: "supported", source: "probe", checked_at: Time.current)
+      connection.capability_verdicts.create!(model_id: "bge-m3", capability: "embeddings",
+                                             state: "supported", source: "admin", checked_at: Time.current)
+      mock_llm_models_response(base_url, body: { object: "list", data: [] }.to_json)
+
+      # A fresh instance, as every caller builds one: the adapter memoises the
+      # fetched list within a run.
+      described_class.new(connection).call
+
+      expect(connection.capability_verdicts.pluck(:source)).to eq(["admin"])
+    end
+  end
+end
diff --git a/spec/workers/llm/sync_models_job_spec.rb b/spec/workers/llm/sync_models_job_spec.rb
new file mode 100644
index 000000000000..90ed7c2ab257
--- /dev/null
+++ b/spec/workers/llm/sync_models_job_spec.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+#-- copyright
+# OpenProject is an open source project management software.
+# Copyright (C) the OpenProject GmbH
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# See COPYRIGHT and LICENSE files for more details.
+#++
+
+require "spec_helper"
+
+RSpec.describe Llm::SyncModelsJob, :llm_server_helpers, :webmock do
+  let(:base_url) { "https://example.com/v1" }
+
+  it "refreshes the model list of every stored connection" do
+    connection = create(:llm_connection, base_url:)
+    request = mock_llm_models_response(base_url)
+
+    described_class.perform_now
+
+    expect(request).to have_been_made.once
+    expect(connection.reload.available_model_ids).to contain_exactly("qwen3.6-27b", "bge-m3")
+  end
+
+  it "does nothing while no connection is stored" do
+    expect { described_class.perform_now }.not_to raise_error
+  end
+end