settings: the assistant's daemon config, tools, and Ask presets

Two settings pages for desktop-assistant.

Assistant edits the daemon's config.toml: server, temperature, tool
rounds, thinking, the system prompt, and the [env] values its tools
read; a switch per tool renames tools/<name>.toml to .toml.off, which
the daemon's glob skips. The daemon reads all of it at startup only, so
the page says when a change is pending and Restart runs assistant.sh
restart, showing its status when the daemon does not come back.

The file is edited line by line, like autostart.lua, so the comments
the example ships with survive: unset keys stay commented out in place.
Every write parses the whole new file with tomllib first and replaces
the old one atomically, so no edit can leave a config the daemon will
not start with. Defaults are read from assistant.py --defaults rather
than copied into QML.

Ask presets edits the canvas's canned questions, which Prefs already
stored for exactly this page: label, question, and the kinds each is
offered for. They apply live.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

11 files changed, 1115 insertions, 2 deletions

diff --git a/desktop/Prefs.qml b/desktop/Prefs.qml
index 1cc83cd..9f89a7f 100644
--- a/desktop/Prefs.qml
+++ b/desktop/Prefs.qml
@@ -51,7 +51,7 @@ Singleton {
         root.write(Object.assign({}, root.doc, { perf: perf }));
     }
 
-    // For the settings page that will edit the presets.
+    // For the settings window's Ask presets page.
     function setPresets(list) {
         root.presets = list;
         const a = Object.assign({}, root.doc.assistant, { presets: list });
diff --git a/desktop/README.md b/desktop/README.md
index 1c7d781..a9d62df 100644
--- a/desktop/README.md
+++ b/desktop/README.md
@@ -68,6 +68,7 @@ and flashes it, so a page needs no highlight code of its own.
     modules/clipboard/   cliphist history: search, copy, delete, clear all
     modules/git/         the global git config, in the settings window
     modules/autostart/   Hyprland's autostart.lua, in the settings window
+    modules/assistant/   desktop-assistant's config, tools, and Ask presets
 
 Sound, mail, vm, network, bluetooth, kdeconnect and ai each carry their own README.
 So does appearance, for its five settings pages.
diff --git a/desktop/assistant/Presets.js b/desktop/assistant/Presets.js
index 057f993..0fd6f31 100644
--- a/desktop/assistant/Presets.js
+++ b/desktop/assistant/Presets.js
@@ -16,7 +16,7 @@
 // without one gets FALLBACK. kinds lists the staged
 // kinds a preset applies to (Files.js); ["many"] offers it whenever two or
 // more files are staged. The list in use is Prefs.presets when one is
-// saved (a settings page will edit it), these otherwise.
+// saved (the settings window's Ask presets page edits it), these otherwise.
 const DEFAULTS = [
     { label: "Summarize", icon: "\uf036", kinds: ["pdf", "text"], prompt: "Summarize this in a few short paragraphs." },
     { label: "Key points", icon: "\uf0ca", kinds: ["pdf"], prompt: "List the key points as bullets." },
diff --git a/desktop/modules/assistant/AssistantModule.qml b/desktop/modules/assistant/AssistantModule.qml
new file mode 100644
index 0000000..bd3e270
--- /dev/null
+++ b/desktop/modules/assistant/AssistantModule.qml
@@ -0,0 +1,175 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// 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.
+
+import Quickshell
+import Quickshell.Io
+import QtQuick
+import "../.."
+import "Config.js" as C
+
+// desktop-assistant's daemon settings: its config.toml, the tools it loads,
+// and a restart, since it reads both only at startup. The module holds the
+// data and the writes; AssistantPage is the view. See README.md.
+Module {
+    id: am
+    name: "assistant"
+    label: "Assistant"
+    // nf-fa-comments, present in Inconsolata Nerd Font.
+    icon: "\uf086"
+    settings: true
+    keywords: ["llm", "model", "llama", "server", "prompt", "temperature", "thinking",
+               "rounds", "tools", "environment", "daemon", "restart"]
+
+    readonly property string home: Quickshell.env("HOME")
+    readonly property string daemonDir: home + "/Programming/GIT/desktop-assistant"
+    readonly property string cfgDir: (Quickshell.env("XDG_CONFIG_HOME") || home + "/.config")
+                                     + "/desktop-assistant"
+    readonly property string cfgPath: cfgDir + "/config.toml"
+    readonly property string toolsDir: cfgDir + "/tools"
+    // The system interpreter, as for calctl: python3 on PATH is a pyenv shim.
+    readonly property string python: "/usr/bin/python3"
+
+    readonly property var keys: ["llm", "system", "tool_rounds", "temperature", "thinking"]
+    readonly property var labels: ({ llm: "Server", system: "System prompt", tool_rounds: "Tool rounds",
+                                     temperature: "Temperature", thinking: "Thinking" })
+
+    // config.toml as last read or written; "" when there is none.
+    property string text: ""
+    readonly property var values: C.scalars(am.text, am.keys)
+    readonly property var envList: C.env(am.text)
+    // The daemon's built-in values, from assistant.py --defaults.
+    property var defaults: ({})
+    // [{name, on, description}]
+    property var tools: []
+    // A write since the last restart, which the daemon has not read yet.
+    property bool pending: false
+    property bool restarting: false
+    property string status: ""
+    property string error: ""
+
+    searchItems: am.keys.map(k => ({ text: am.labels[k], key: "key:" + k }))
+        .concat(am.envList.map(e => ({ text: e.key + " = " + e.value, key: "env:" + e.key })))
+        .concat(am.tools.map(t => ({ text: "tool: " + t.name, key: "tool:" + t.name })))
+
+    function refresh() {
+        fv.reload();
+        am.listTools();
+        if (Object.keys(am.defaults).length === 0)
+            am.run([am.python, am.daemonDir + "/assistant.py", "--defaults"], null, (code, out) => {
+                try { if (code === 0) am.defaults = JSON.parse(out); } catch (e) {}
+            });
+    }
+
+    property FileView fv: FileView {
+        path: am.cfgPath
+        watchChanges: true
+        printErrors: false
+        onFileChanged: reload()
+        onLoaded: am.text = text()
+        onLoadFailed: am.text = ""
+    }
+
+    // One Process per call, so calls never share one (a running Process
+    // ignores a second start, AGENTS.md). input, when not null, is written
+    // to stdin and stdin closed. cb(code, stdout, stderr) runs once the exit
+    // and both streams are in, which arrive in no fixed order.
+    function run(cmd, input, cb) {
+        op.createObject(am, { command: cmd, input: input, cb: cb, stdinEnabled: input !== null }).running = true;
+    }
+    property Component op: Component {
+        Process {
+            id: proc
+            property var input: null
+            property var cb: null
+            property int left: 3
+            property int code: -1
+            property string out: ""
+            property string err: ""
+            function step() {
+                if (--left > 0) return;
+                try { if (proc.cb) proc.cb(proc.code, proc.out, proc.err); }
+                finally { proc.destroy(); }
+            }
+            onStarted: if (proc.input !== null) { proc.write(proc.input); proc.stdinEnabled = false; }
+            onExited: code => { proc.code = code; proc.step(); }
+            stdout: StdioCollector { onStreamFinished: { proc.out = text; proc.step(); } }
+            stderr: StdioCollector { onStreamFinished: { proc.err = text; proc.step(); } }
+        }
+    }
+
+    // Validates the whole file with tomllib before it replaces the old one,
+    // atomically, so a bad edit can never leave a config the daemon refuses
+    // to start with.
+    readonly property string writer: "import os, sys, tomllib\n"
+        + "t = sys.stdin.read()\n"
+        + "try:\n    tomllib.loads(t)\n"
+        + "except tomllib.TOMLDecodeError as e:\n    sys.exit(f'not valid TOML: {e}')\n"
+        + "p = sys.argv[1]\nos.makedirs(os.path.dirname(p), exist_ok=True)\n"
+        + "with open(p + '.tmp', 'w') as f:\n    f.write(t)\n"
+        + "os.replace(p + '.tmp', p)\n"
+
+    function save(t) {
+        am.run([am.python, "-c", am.writer, am.cfgPath], t, (code, out, err) => {
+            if (code === 0) { am.text = t; am.pending = true; am.error = ""; }
+            else am.error = err.trim() || "config.toml could not be written";
+        });
+    }
+    // toml is the value written as TOML, or null to fall back to the default.
+    function setKey(key, toml) { am.save(C.setScalar(am.text, key, toml)); }
+    function setEnv(key, value) { am.save(C.setEnv(am.text, key, value)); }
+    function quote(s) { return C.quote(s); }
+
+    // Every tools/*.toml is loaded; *.toml.off is the same file switched off.
+    readonly property string lister: "import glob, json, os, sys, tomllib\n"
+        + "out = []\n"
+        + "for p in glob.glob(sys.argv[1] + '/*.toml') + glob.glob(sys.argv[1] + '/*.toml.off'):\n"
+        + "    on = p.endswith('.toml')\n"
+        + "    name = os.path.basename(p).removesuffix('.off').removesuffix('.toml')\n"
+        + "    try:\n        d = tomllib.load(open(p, 'rb')).get('description', '')\n"
+        + "    except Exception as e:\n        d = f'unreadable: {e}'\n"
+        + "    out.append({'name': name, 'on': on, 'description': d})\n"
+        + "print(json.dumps(sorted(out, key=lambda t: t['name'])))\n"
+
+    function listTools() {
+        am.run([am.python, "-c", am.lister, am.toolsDir], null, (code, out) => {
+            try { if (code === 0) am.tools = JSON.parse(out); } catch (e) {}
+        });
+    }
+
+    function toggleTool(t) {
+        const on = am.toolsDir + "/" + t.name + ".toml";
+        const off = on + ".off";
+        // -n: never overwrite a file that already holds the other name.
+        am.run(["mv", "-n", t.on ? on : off, t.on ? off : on], null, (code, out, err) => {
+            if (code === 0) { am.pending = true; am.error = ""; }
+            else am.error = err.trim() || "could not switch " + t.name;
+            am.listTools();
+        });
+    }
+
+    function restart() {
+        am.restarting = true;
+        am.run([am.daemonDir + "/assistant.sh", "restart"], null, (code, out) => {
+            am.restarting = false;
+            // assistant.sh ends on its status: the process, the socket, and
+            // the log's tail, which is where a refused config says why.
+            am.status = code === 0 ? "Restarted." : out.trim();
+            if (code === 0) am.pending = false;
+        });
+    }
+
+    page: Component {
+        Page {
+            title: "Assistant"
+            AssistantPage { width: parent.width; asst: am }
+        }
+    }
+}
diff --git a/desktop/modules/assistant/AssistantPage.qml b/desktop/modules/assistant/AssistantPage.qml
new file mode 100644
index 0000000..e5d76c8
--- /dev/null
+++ b/desktop/modules/assistant/AssistantPage.qml
@@ -0,0 +1,420 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// 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.
+
+import QtQuick
+import QtQuick.Controls
+import "../.."
+
+// The view over AssistantModule: the model settings, the tools' environment,
+// the tools themselves, and the restart that applies them. A field saves on
+// Enter; emptied, it falls back to the daemon's default, which it shows as
+// its placeholder.
+Column {
+    id: page
+    spacing: 8
+
+    // The module. Not named `am`, its id (it would bind to itself).
+    required property QtObject asst
+
+    readonly property var v: asst.values
+    readonly property var d: asst.defaults
+
+    // What the daemon would run with: the file's value, else the default.
+    function shown(key) {
+        const x = page.v[key] !== undefined ? page.v[key] : page.d[key];
+        return x === undefined || x === null ? "" : String(x);
+    }
+
+    component Small: Text {
+        color: Theme.subtext
+        font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 4 }
+    }
+
+    component Heading: Text {
+        topPadding: 14
+        font { family: Theme.fontFamily; pixelSize: Theme.fontSize; bold: true }
+        color: Theme.text
+    }
+
+    // A one-line input that saves on Enter and undoes on Escape; edited
+    // reports every keystroke, for the add row.
+    component Field: Rectangle {
+        id: field
+        property string value: ""
+        property string placeholder: ""
+        signal commit(string text)
+        signal edited(string text)
+        // Commit on Enter even when unchanged: the add row's fields track
+        // their value as they are typed, so they never differ from it.
+        property bool live: false
+        height: 34
+        radius: 8
+        color: Theme.surface
+        TextInput {
+            id: ti
+            anchors { fill: parent; leftMargin: 10; rightMargin: 10 }
+            verticalAlignment: TextInput.AlignVCenter
+            clip: true
+            selectByMouse: true
+            color: Theme.text
+            font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 2 }
+            text: field.value
+            onTextEdited: field.edited(text)
+            onAccepted: if (field.live || text !== field.value) field.commit(text)
+            Keys.onEscapePressed: event => {
+                if (text !== field.value) text = field.value;
+                else event.accepted = false;
+            }
+            Text {
+                anchors.verticalCenter: parent.verticalCenter
+                width: parent.width
+                elide: Text.ElideRight
+                visible: parent.text === ""
+                text: field.placeholder
+                color: Theme.overlay
+                font: parent.font
+            }
+        }
+    }
+
+    // A labelled row: label on the left, the control filling the rest.
+    component Labelled: Item {
+        property alias label: lbl.text
+        default property alias control: slot.data
+        width: page.width
+        height: 34
+        Text {
+            id: lbl
+            anchors { left: parent.left; verticalCenter: parent.verticalCenter }
+            width: 120
+            color: Theme.subtext
+            font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 3 }
+        }
+        Item {
+            id: slot
+            anchors { left: lbl.right; leftMargin: 8; right: parent.right; top: parent.top; bottom: parent.bottom }
+        }
+    }
+
+    // --- restart ---
+
+    Rectangle {
+        width: page.width
+        height: bar.implicitHeight + 20
+        radius: 10
+        color: page.asst.pending ? Qt.alpha(Theme.accent, 0.16) : Qt.alpha(Theme.surface, 0.35)
+        border.width: 1
+        border.color: page.asst.pending ? Qt.alpha(Theme.accent, 0.5) : Qt.alpha(Theme.text, 0.08)
+
+        Column {
+            id: bar
+            anchors { left: parent.left; right: parent.right; verticalCenter: parent.verticalCenter; margins: 12 }
+            spacing: 6
+
+            Item {
+                width: parent.width
+                height: 30
+                Text {
+                    anchors { left: parent.left; right: restartBtn.left; rightMargin: 8; verticalCenter: parent.verticalCenter }
+                    wrapMode: Text.Wrap
+                    text: page.asst.pending ? "Saved. The assistant reads these at startup: restart it to apply."
+                                            : "The assistant reads these at startup."
+                    color: Theme.text
+                    font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 3 }
+                }
+                Button {
+                    id: restartBtn
+                    anchors { right: parent.right; verticalCenter: parent.verticalCenter }
+                    text: page.asst.restarting ? "Restarting…" : "Restart assistant"
+                    enabled: !page.asst.restarting
+                    onClicked: page.asst.restart()
+                }
+            }
+
+            Small {
+                width: parent.width
+                visible: page.asst.status !== ""
+                wrapMode: Text.Wrap
+                text: page.asst.status
+                color: page.asst.status === "Restarted." ? Theme.green : Theme.red
+            }
+        }
+    }
+
+    Text {
+        width: page.width
+        visible: page.asst.error !== ""
+        wrapMode: Text.Wrap
+        text: page.asst.error
+        color: Theme.red
+        font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 4 }
+    }
+
+    // --- model ---
+
+    Heading { text: "Model" }
+
+    Labelled {
+        objectName: "key:llm"
+        label: "Server"
+        Field {
+            anchors.fill: parent
+            value: page.v.llm ?? ""
+            placeholder: page.d.llm ?? ""
+            onCommit: t => page.asst.setKey("llm", t.trim() ? page.asst.quote(t.trim()) : null)
+        }
+    }
+
+    Labelled {
+        objectName: "key:temperature"
+        label: "Temperature"
+        Field {
+            id: temp
+            anchors { left: parent.left; top: parent.top; bottom: parent.bottom }
+            width: 120
+            value: page.v.temperature !== undefined ? String(page.v.temperature) : ""
+            placeholder: "the model's preset"
+            onCommit: t => {
+                const x = Number(t.trim());
+                if (t.trim() === "") page.asst.setKey("temperature", null);
+                else if (!isNaN(x) && x >= 0 && x <= 2) page.asst.setKey("temperature", String(x));
+                else page.asst.error = "Temperature is a number from 0 to 2.";
+            }
+        }
+        Small {
+            anchors { left: temp.right; leftMargin: 10; verticalCenter: parent.verticalCenter }
+            text: "0 to 2; empty uses the llama-server preset's"
+        }
+    }
+
+    Labelled {
+        objectName: "key:tool_rounds"
+        label: "Tool rounds"
+        Field {
+            id: rounds
+            anchors { left: parent.left; top: parent.top; bottom: parent.bottom }
+            width: 120
+            value: page.v.tool_rounds !== undefined ? String(page.v.tool_rounds) : ""
+            placeholder: page.d.tool_rounds !== undefined ? String(page.d.tool_rounds) : ""
+            onCommit: t => {
+                const n = Number(t.trim());
+                if (t.trim() === "") page.asst.setKey("tool_rounds", null);
+                else if (Number.isInteger(n) && n >= 0 && n <= 20) page.asst.setKey("tool_rounds", String(n));
+                else page.asst.error = "Tool rounds is a whole number from 0 to 20.";
+            }
+        }
+        Small {
+            anchors { left: rounds.right; leftMargin: 10; verticalCenter: parent.verticalCenter }
+            text: "tool round trips per question"
+        }
+    }
+
+    Labelled {
+        objectName: "key:thinking"
+        label: "Thinking"
+        Switch {
+            id: think
+            anchors.verticalCenter: parent.verticalCenter
+            checked: page.shown("thinking") !== "false"
+            onToggled: page.asst.setKey("thinking", checked ? "true" : "false")
+        }
+        Small {
+            anchors { left: think.right; leftMargin: 10; verticalCenter: parent.verticalCenter }
+            text: "off skips the model's reasoning: a faster first word"
+        }
+    }
+
+    // The prompt is long and multi-line, so it gets its own box and an
+    // explicit Save rather than Enter.
+    Column {
+        objectName: "key:system"
+        width: page.width
+        spacing: 6
+
+        Text {
+            text: "System prompt"
+            color: Theme.subtext
+            font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 3 }
+        }
+
+        Rectangle {
+            width: parent.width
+            height: 130
+            radius: 8
+            color: Theme.surface
+
+            ScrollView {
+                anchors { fill: parent; margins: 8 }
+                TextArea {
+                    id: prompt
+                    wrapMode: TextEdit.Wrap
+                    selectByMouse: true
+                    color: Theme.text
+                    font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 3 }
+                    background: null
+                    padding: 0
+                    text: page.shown("system")
+                }
+            }
+        }
+
+        Row {
+            spacing: 8
+            Button {
+                text: "Save prompt"
+                enabled: prompt.text.trim() !== "" && prompt.text !== page.shown("system")
+                onClicked: page.asst.setKey("system", prompt.text === page.d.system ? null
+                                                      : page.asst.quote(prompt.text))
+            }
+            Button {
+                text: "Use the default"
+                enabled: page.v.system !== undefined
+                onClicked: page.asst.setKey("system", null)
+            }
+            Small {
+                anchors.verticalCenter: parent.verticalCenter
+                text: page.v.system !== undefined ? "custom" : "default"
+            }
+        }
+    }
+
+    // --- env ---
+
+    Heading { text: "Tool environment" }
+    Small {
+        width: page.width
+        wrapMode: Text.Wrap
+        text: "Added to every tool's environment: instance URLs, key file paths."
+    }
+
+    property string confirming: ""
+
+    Repeater {
+        model: page.asst.envList
+
+        delegate: Item {
+            id: envRow
+            required property var modelData
+            objectName: "env:" + modelData.key
+            width: page.width
+            height: 34
+
+            Text {
+                id: envKey
+                anchors { left: parent.left; verticalCenter: parent.verticalCenter }
+                width: 120
+                elide: Text.ElideRight
+                text: envRow.modelData.key
+                color: Theme.subtext
+                font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 3 }
+            }
+            Field {
+                anchors { left: envKey.right; leftMargin: 8; right: envDel.left; rightMargin: 8; top: parent.top; bottom: parent.bottom }
+                value: envRow.modelData.value
+                onCommit: t => page.asst.setEnv(envRow.modelData.key, t)
+            }
+            Button {
+                id: envDel
+                anchors { right: parent.right; verticalCenter: parent.verticalCenter }
+                danger: true
+                text: page.confirming === envRow.modelData.key ? "Confirm" : "Remove"
+                onClicked: {
+                    if (page.confirming === envRow.modelData.key) {
+                        page.confirming = "";
+                        page.asst.setEnv(envRow.modelData.key, null);
+                    } else page.confirming = envRow.modelData.key;
+                }
+            }
+        }
+    }
+
+    // The add row: a key, a value, Add.
+    property string newKey: ""
+    property string newValue: ""
+    readonly property bool keyOk: /^[A-Za-z_][A-Za-z0-9_]*$/.test(page.newKey)
+                                  && !page.asst.envList.some(e => e.key === page.newKey)
+    function addEnv() {
+        if (!page.keyOk) return;
+        page.asst.setEnv(page.newKey, page.newValue);
+        page.newKey = "";
+        page.newValue = "";
+    }
+
+    Item {
+        width: page.width
+        height: 34
+        Field {
+            id: keyField
+            anchors { left: parent.left; top: parent.top; bottom: parent.bottom }
+            width: 120
+            value: page.newKey
+            placeholder: "NEW_KEY"
+            onEdited: t => page.newKey = t
+        }
+        Field {
+            anchors { left: keyField.right; leftMargin: 8; right: addBtn.left; rightMargin: 8; top: parent.top; bottom: parent.bottom }
+            value: page.newValue
+            placeholder: "value"
+            live: true
+            onEdited: t => page.newValue = t
+            onCommit: page.addEnv()
+        }
+        Button {
+            id: addBtn
+            anchors { right: parent.right; verticalCenter: parent.verticalCenter }
+            text: "Add"
+            enabled: page.keyOk
+            onClicked: page.addEnv()
+        }
+    }
+
+    // --- tools ---
+
+    Heading { text: "Tools" }
+    Small {
+        width: page.width
+        wrapMode: Text.Wrap
+        text: "What the model may call. Off renames the file to .toml.off, which the daemon skips."
+    }
+
+    Repeater {
+        model: page.asst.tools
+
+        delegate: Item {
+            id: toolRow
+            required property var modelData
+            objectName: "tool:" + modelData.name
+            width: page.width
+            height: Math.max(40, toolText.implicitHeight + 10)
+
+            Switch {
+                id: toolSw
+                anchors { left: parent.left; verticalCenter: parent.verticalCenter }
+                checked: toolRow.modelData.on
+                onToggled: page.asst.toggleTool(toolRow.modelData)
+            }
+            Column {
+                id: toolText
+                anchors { left: toolSw.right; leftMargin: 10; right: parent.right; verticalCenter: parent.verticalCenter }
+                Text {
+                    text: toolRow.modelData.name
+                    color: toolRow.modelData.on ? Theme.text : Theme.subtext
+                    font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 2; bold: true }
+                }
+                Small {
+                    width: parent.width
+                    wrapMode: Text.Wrap
+                    text: toolRow.modelData.description
+                }
+            }
+        }
+    }
+}
diff --git a/desktop/modules/assistant/Config.js b/desktop/modules/assistant/Config.js
new file mode 100644
index 0000000..c30ea8b
--- /dev/null
+++ b/desktop/modules/assistant/Config.js
@@ -0,0 +1,142 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// 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.
+
+.pragma library
+
+// Pure helpers for desktop-assistant's config.toml, tested by
+// test_config.js under node.
+//
+// The file is edited line by line so its comments survive: the example it
+// is copied from documents every key in place. Only the shapes this page
+// writes are understood: top-level `key = value` before the first table,
+// and `KEY = "value"` lines in [env]. A top-level key that is unset sits
+// commented out (`# key = value`), which is how the example ships, so
+// setting one activates its line and unsetting comments it back out.
+// ponytail: no multi-line strings or arrays; the page never writes one,
+// and Save validates the whole file with tomllib before writing.
+
+const KEY = /^(\s*)(#\s*)?([A-Za-z_][A-Za-z0-9_]*)\s*=\s*(.*)$/;
+const HEADER = /^\s*\[/;
+
+function quote(s) {
+    return '"' + String(s).replace(/[\\"]/g, c => "\\" + c)
+        .replace(/\n/g, "\\n").replace(/\t/g, "\\t").replace(/\r/g, "\\r") + '"';
+}
+
+// The value at the start of rest and where it ends, so what follows (an
+// inline comment) can be kept.
+function value(rest) {
+    if (rest.startsWith('"')) {
+        let out = "";
+        for (let i = 1; i < rest.length; i++) {
+            const c = rest[i];
+            if (c === '"') return { v: out, end: i + 1 };
+            if (c === "\\" && i + 1 < rest.length) {
+                const n = rest[++i];
+                out += n === "n" ? "\n" : n === "t" ? "\t" : n === "r" ? "\r" : n;
+            } else out += c;
+        }
+        return { v: out, end: rest.length };
+    }
+    const m = /^[^\s#]*/.exec(rest)[0];
+    const v = m === "true" ? true : m === "false" ? false
+            : m !== "" && !isNaN(Number(m)) ? Number(m) : m;
+    return { v: v, end: m.length };
+}
+
+function firstHeader(lines) {
+    const i = lines.findIndex(l => HEADER.test(l) && !/^\s*#/.test(l));
+    return i < 0 ? lines.length : i;
+}
+
+// {key: value} for the active top-level keys among keys.
+function scalars(text, keys) {
+    const lines = text.split("\n");
+    const out = {};
+    for (let i = 0; i < firstHeader(lines); i++) {
+        const m = KEY.exec(lines[i]);
+        if (m && !m[2] && keys.includes(m[3])) out[m[3]] = value(m[4]).v;
+    }
+    return out;
+}
+
+// toml is the value already written as TOML (quote() for a string), or null
+// to unset.
+function setScalar(text, key, toml) {
+    const lines = text.split("\n");
+    const end = firstHeader(lines);
+    let commented = -1;
+    for (let i = 0; i < end; i++) {
+        const m = KEY.exec(lines[i]);
+        if (!m || m[3] !== key) continue;
+        if (!m[2]) {
+            const tail = m[4].slice(value(m[4]).end);
+            lines[i] = toml === null ? m[1] + "# " + key + " = " + m[4]
+                                     : m[1] + key + " = " + toml + tail;
+            return lines.join("\n");
+        }
+        if (commented < 0) commented = i;
+    }
+    if (toml === null) return text;
+    if (commented >= 0) {
+        const m = KEY.exec(lines[commented]);
+        lines[commented] = m[1] + key + " = " + toml + m[4].slice(value(m[4]).end);
+    } else {
+        // Before the blank line that separates the first table, if any.
+        const at = end > 0 && lines[end - 1].trim() === "" ? end - 1 : end;
+        lines.splice(at, 0, key + " = " + toml);
+    }
+    return lines.join("\n");
+}
+
+function envRange(lines) {
+    const h = lines.findIndex(l => /^\s*\[env\]\s*(#.*)?$/.test(l));
+    if (h < 0) return null;
+    let e = lines.findIndex((l, i) => i > h && HEADER.test(l));
+    return { h: h, end: e < 0 ? lines.length : e };
+}
+
+// [{key, value}] for the active lines of [env], in file order.
+function env(text) {
+    const lines = text.split("\n");
+    const r = envRange(lines);
+    if (!r) return [];
+    const out = [];
+    for (let i = r.h + 1; i < r.end; i++) {
+        const m = KEY.exec(lines[i]);
+        if (m && !m[2]) out.push({ key: m[3], value: String(value(m[4]).v) });
+    }
+    return out;
+}
+
+// value is a plain string, quoted here; null removes the key.
+function setEnv(text, key, val) {
+    const lines = text.split("\n");
+    const r = envRange(lines);
+    if (!r) {
+        if (val === null) return text;
+        return text.replace(/\n*$/, "") + "\n\n[env]\n" + key + " = " + quote(val) + "\n";
+    }
+    let last = r.h;
+    for (let i = r.h + 1; i < r.end; i++) {
+        const m = KEY.exec(lines[i]);
+        if (!m || m[2]) continue;
+        if (m[3] === key) {
+            if (val === null) lines.splice(i, 1);
+            else lines[i] = m[1] + key + " = " + quote(val) + m[4].slice(value(m[4]).end);
+            return lines.join("\n");
+        }
+        last = i;
+    }
+    if (val === null) return text;
+    lines.splice(last + 1, 0, key + " = " + quote(val));
+    return lines.join("\n");
+}
diff --git a/desktop/modules/assistant/PresetsModule.qml b/desktop/modules/assistant/PresetsModule.qml
new file mode 100644
index 0000000..9490bf7
--- /dev/null
+++ b/desktop/modules/assistant/PresetsModule.qml
@@ -0,0 +1,34 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// 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.
+
+import QtQuick
+import "../.."
+import "../../assistant/Presets.js" as Presets
+
+// The assistant canvas's Ask row: the canned questions offered for the
+// staged files. They live in Prefs and the canvas reads them live, so
+// unlike the daemon's settings these need no restart.
+Module {
+    name: "presets"
+    label: "Ask presets"
+    // nf-fa-lightbulb_o, present in Inconsolata Nerd Font.
+    icon: ""
+    settings: true
+    keywords: ["assistant", "canvas", "ask", "question", "prompt", "summarize", "files"]
+    searchItems: Presets.list(Prefs.presets).map((p, i) => ({ text: p.label + ": " + p.prompt, key: "preset:" + i }))
+
+    page: Component {
+        Page {
+            title: "Ask presets"
+            PresetsPage { width: parent.width }
+        }
+    }
+}
diff --git a/desktop/modules/assistant/PresetsPage.qml b/desktop/modules/assistant/PresetsPage.qml
new file mode 100644
index 0000000..ec103cf
--- /dev/null
+++ b/desktop/modules/assistant/PresetsPage.qml
@@ -0,0 +1,215 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// 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.
+
+import QtQuick
+import "../.."
+import "../../assistant/Presets.js" as Presets
+
+// One card per preset: its label and question, saved on Enter, and the file
+// kinds it is offered for. Every change saves the whole list to Prefs; Reset
+// drops the saved list, which brings the built-in one back.
+Column {
+    id: page
+    spacing: 10
+
+    readonly property var list: Presets.list(Prefs.presets)
+    // The kinds a preset can name: the four the canvas chats about, and
+    // "many", offered whenever two or more files are staged.
+    readonly property var kinds: ["pdf", "text", "code", "image", "many"]
+    property string error: ""
+    property int confirming: -1
+
+    // Saves a copy of the list with entry i replaced by fn(entry), or
+    // removed when fn returns null.
+    function edit(i, fn) {
+        const out = [];
+        page.list.forEach((p, j) => {
+            const c = { label: p.label, icon: p.icon, kinds: p.kinds.slice(), prompt: p.prompt };
+            if (j !== i) { out.push(c); return; }
+            const r = fn(c);
+            if (r) out.push(r);
+        });
+        page.error = "";
+        page.confirming = -1;
+        Prefs.setPresets(out);
+    }
+
+    function add() {
+        Prefs.setPresets(page.list.concat([{ label: "New preset", icon: Presets.FALLBACK,
+                                             kinds: ["text"], prompt: "Summarize this." }]));
+    }
+
+    component Small: Text {
+        color: Theme.subtext
+        font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 4 }
+    }
+
+    component Field: Rectangle {
+        id: field
+        property string value: ""
+        property string placeholder: ""
+        signal commit(string text)
+        height: 32
+        radius: 8
+        color: Qt.alpha(Theme.base, 0.6)
+        TextInput {
+            anchors { fill: parent; leftMargin: 10; rightMargin: 10 }
+            verticalAlignment: TextInput.AlignVCenter
+            clip: true
+            selectByMouse: true
+            color: Theme.text
+            font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 3 }
+            text: field.value
+            onAccepted: if (text !== field.value) field.commit(text)
+            Keys.onEscapePressed: event => {
+                if (text !== field.value) text = field.value;
+                else event.accepted = false;
+            }
+            Text {
+                anchors.verticalCenter: parent.verticalCenter
+                visible: parent.text === ""
+                text: field.placeholder
+                color: Theme.overlay
+                font: parent.font
+            }
+        }
+    }
+
+    Small {
+        width: page.width
+        wrapMode: Text.Wrap
+        text: "Offered on the assistant canvas for the staged files: a preset shows when every staged file is "
+            + "one of its kinds, or, with \"many\", when two or more are staged. Enter saves a field; "
+            + "changes apply at once."
+    }
+
+    Text {
+        width: page.width
+        visible: page.error !== ""
+        wrapMode: Text.Wrap
+        text: page.error
+        color: Theme.red
+        font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 4 }
+    }
+
+    Repeater {
+        model: page.list
+
+        delegate: Rectangle {
+            id: card
+            required property var modelData
+            required property int index
+            objectName: "preset:" + index
+            width: page.width
+            height: body.implicitHeight + 20
+            radius: 10
+            color: Qt.alpha(Theme.surface, 0.45)
+
+            Column {
+                id: body
+                anchors { left: parent.left; right: parent.right; top: parent.top; margins: 10 }
+                spacing: 8
+
+                Item {
+                    width: parent.width
+                    height: 32
+                    Text {
+                        id: glyph
+                        anchors { left: parent.left; verticalCenter: parent.verticalCenter }
+                        width: 24
+                        text: card.modelData.icon ?? Presets.FALLBACK
+                        font { family: Theme.iconFamily; pixelSize: Theme.fontSize }
+                        color: Theme.text
+                    }
+                    Field {
+                        anchors { left: glyph.right; leftMargin: 6; right: del.left; rightMargin: 8; top: parent.top; bottom: parent.bottom }
+                        value: card.modelData.label
+                        placeholder: "label"
+                        onCommit: t => {
+                            if (t.trim() === "") { page.error = "A preset needs a label."; return; }
+                            page.edit(card.index, c => Object.assign(c, { label: t.trim() }));
+                        }
+                    }
+                    Button {
+                        id: del
+                        anchors { right: parent.right; verticalCenter: parent.verticalCenter }
+                        danger: true
+                        text: page.confirming === card.index ? "Confirm" : "Remove"
+                        onClicked: {
+                            if (page.confirming === card.index) page.edit(card.index, c => null);
+                            else page.confirming = card.index;
+                        }
+                    }
+                }
+
+                Field {
+                    width: parent.width
+                    value: card.modelData.prompt
+                    placeholder: "the question asked"
+                    onCommit: t => {
+                        if (t.trim() === "") { page.error = "A preset needs a question."; return; }
+                        page.edit(card.index, c => Object.assign(c, { prompt: t.trim() }));
+                    }
+                }
+
+                // A kind toggles on click; the last one cannot be cleared,
+                // since a preset with no kinds would never be offered.
+                Flow {
+                    width: parent.width
+                    spacing: 6
+                    Repeater {
+                        model: page.kinds
+                        Rectangle {
+                            id: chip
+                            required property string modelData
+                            readonly property bool on: card.modelData.kinds.includes(modelData)
+                            implicitWidth: chipText.implicitWidth + 20
+                            implicitHeight: 26
+                            radius: 13
+                            color: on ? Qt.alpha(Theme.accent, 0.85)
+                                 : chipArea.containsMouse ? Qt.alpha(Theme.accent, 0.22) : Qt.alpha(Theme.base, 0.6)
+                            Text {
+                                id: chipText
+                                anchors.centerIn: parent
+                                text: chip.modelData
+                                color: chip.on ? Theme.base : Theme.text
+                                font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 4 }
+                            }
+                            MouseArea {
+                                id: chipArea
+                                anchors.fill: parent
+                                hoverEnabled: true
+                                cursorShape: Qt.PointingHandCursor
+                                onClicked: {
+                                    const ks = card.modelData.kinds;
+                                    if (chip.on && ks.length === 1) { page.error = "A preset needs at least one kind."; return; }
+                                    page.edit(card.index, c => Object.assign(c, {
+                                        kinds: chip.on ? ks.filter(k => k !== chip.modelData) : ks.concat([chip.modelData]) }));
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    Row {
+        spacing: 8
+        Button { text: "Add preset"; onClicked: page.add() }
+        Button {
+            text: "Reset to defaults"
+            danger: true
+            enabled: Prefs.presets !== null
+            onClicked: Prefs.resetPresets()
+        }
+    }
+}
diff --git a/desktop/modules/assistant/README.md b/desktop/modules/assistant/README.md
new file mode 100644
index 0000000..347f9ea
--- /dev/null
+++ b/desktop/modules/assistant/README.md
@@ -0,0 +1,34 @@
+# assistant
+
+Two settings pages for desktop-assistant, the daemon behind the assistant
+canvas (`../../assistant/`).
+
+**Assistant** edits the daemon's `~/.config/desktop-assistant/config.toml`
+and switches its tools. The model fields (server, temperature, tool rounds,
+thinking) save on Enter, and an emptied field falls back to the daemon's
+default, shown as its placeholder; the defaults come from `assistant.py
+--defaults`, so they are never copied here. The system prompt has its own
+box, Save and "Use the default". The tool environment (`[env]`) is one row
+per key, with an add row below. A tool's switch renames `tools/<name>.toml`
+to `<name>.toml.off`, which the daemon's `*.toml` glob skips.
+
+The daemon reads all of this only at startup, so after a change the page
+says so and offers Restart, which runs `assistant.sh restart`; a daemon that
+does not come back shows the script's status, whose log tail says why.
+
+The file is edited line by line (`Config.js`) so the comments the example
+ships with survive: an unset key sits commented out, setting it activates
+its line, and unsetting comments it back out. Every write first parses the
+whole new file with `tomllib`, then replaces the old one atomically, so an
+edit can never leave a config the daemon refuses to start with.
+
+**Ask presets** edits the canvas's canned questions for staged files:
+label, question, and the file kinds each is offered for. They live in
+`Prefs` and the canvas reads them live, so changes apply at once; "Reset to
+defaults" drops the saved list and brings back the built-in one in
+`../../assistant/Presets.js`. A new preset gets the fallback icon.
+
+Search finds the model fields, every `[env]` key, every tool and every
+preset by name.
+
+Check: `node desktop/modules/assistant/test_config.js`.
diff --git a/desktop/modules/assistant/test_config.js b/desktop/modules/assistant/test_config.js
new file mode 100644
index 0000000..cc610a8
--- /dev/null
+++ b/desktop/modules/assistant/test_config.js
@@ -0,0 +1,89 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// 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.
+
+// Run: node desktop/modules/assistant/test_config.js
+// Config.js is a QML library, so its .pragma line is stripped before node
+// evaluates it.
+
+const fs = require("fs");
+const assert = require("assert");
+
+const src = fs.readFileSync(__dirname + "/Config.js", "utf8")
+    .replace(/^\.pragma library$/m, "");
+const C = new Function(src + "\nreturn { scalars, setScalar, env, setEnv, quote };")();
+
+const KEYS = ["llm", "system", "tool_rounds", "temperature", "thinking"];
+const file = [
+    "# desktop-assistant configuration.",
+    "# Style name = weight; prose with an equals sign",
+    "",
+    '# llm = "http://localhost:8181/v1"    # llama-server, OpenAI API',
+    '# system = "You are a voice assistant. ..."',
+    "temperature = 0.6                    # per request; unset = the preset's",
+    "",
+    "# [whisper]",
+    "# port = 8182",
+    "",
+    "[env]",
+    'SEARXNG_URL = "http://search.example.org"   # a # inside a comment',
+    'MD_EDITOR = "typora"',
+    '# WEATHER_ENV = "/home/you/x"',
+    "",
+].join("\n");
+
+// Only active keys have values; prose and commented keys do not.
+assert.deepStrictEqual(C.scalars(file, KEYS), { temperature: 0.6 });
+assert.deepStrictEqual(C.env(file), [
+    { key: "SEARXNG_URL", value: "http://search.example.org" },
+    { key: "MD_EDITOR", value: "typora" },
+]);
+
+// Setting an active key keeps its inline comment.
+let t = C.setScalar(file, "temperature", "0.2");
+assert.strictEqual(t.split("\n")[5], "temperature = 0.2                    # per request; unset = the preset's");
+// Unsetting comments it out in place, and it reads as unset.
+t = C.setScalar(file, "temperature", null);
+assert.strictEqual(t.split("\n")[5], "# temperature = 0.6                    # per request; unset = the preset's");
+assert.deepStrictEqual(C.scalars(t, KEYS), {});
+// Setting a commented key activates its line rather than adding one.
+t = C.setScalar(file, "llm", C.quote("http://box:8080/v1"));
+assert.strictEqual(t.split("\n")[3], 'llm = "http://box:8080/v1"    # llama-server, OpenAI API');
+assert.strictEqual(t.split("\n").length, file.split("\n").length);
+// A key nowhere in the file lands before the first table, not inside it.
+t = C.setScalar(file, "thinking", "false");
+const lines = t.split("\n");
+assert.ok(lines.indexOf("thinking = false") < lines.indexOf("[env]"));
+assert.strictEqual(C.scalars(t, KEYS).thinking, false);
+// The prose line with "=" is never treated as a key.
+assert.strictEqual(C.setScalar(file, "name", null), file);
+
+// Strings round-trip with quotes, backslashes and newlines.
+const tricky = 'Say "hi"\\now\nline two\ttab';
+t = C.setScalar(file, "system", C.quote(tricky));
+assert.strictEqual(C.scalars(t, KEYS).system, tricky);
+assert.strictEqual(t.split("\n").length, file.split("\n").length);
+
+// env: replace, remove, add after the last active entry.
+t = C.setEnv(file, "MD_EDITOR", "xdg-open");
+assert.deepStrictEqual(C.env(t)[1], { key: "MD_EDITOR", value: "xdg-open" });
+t = C.setEnv(file, "SEARXNG_URL", null);
+assert.deepStrictEqual(C.env(t).map(e => e.key), ["MD_EDITOR"]);
+t = C.setEnv(file, "CALENDAR_DIR", "/home/you/cal");
+assert.deepStrictEqual(C.env(t).map(e => e.key), ["SEARXNG_URL", "MD_EDITOR", "CALENDAR_DIR"]);
+assert.strictEqual(t.split("\n")[13], 'CALENDAR_DIR = "/home/you/cal"');
+// No [env] table yet: one is appended.
+t = C.setEnv("temperature = 0.6\n", "X", "1");
+assert.deepStrictEqual(C.env(t), [{ key: "X", value: "1" }]);
+assert.ok(/\n\[env\]\nX = "1"\n$/.test(t), JSON.stringify(t));
+// An env key in another table is not the env one.
+assert.deepStrictEqual(C.env('[voice]\nlang = "it"\n'), []);
+
+console.log("test_config: ok");
diff --git a/desktop/shell.qml b/desktop/shell.qml
index 3cbfe51..ec58936 100644
--- a/desktop/shell.qml
+++ b/desktop/shell.qml
@@ -19,6 +19,7 @@ import Quickshell.Wayland
 import QtQuick
 import "modules/ai"
 import "modules/appearance"
+import "modules/assistant"
 import "modules/autostart"
 import "modules/bluetooth"
 import "modules/clipboard"
@@ -80,6 +81,8 @@ ShellRoot {
             SunsetModule {},
             IdleModule {},
             AutostartModule {},
+            AssistantModule {},
+            PresetsModule {},
             GitModule {},
         ]
     }