Extend coach proposal with allowed window classes

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

internal/ai/coach.go

@@ -33,12 +33,13 @@ func buildPrompt(intent string) string {
 	return `You are a focus coach. The user gives a rough intent for a work session. Turn it into ONE concrete, actionable commitment.
 
 Respond with ONLY a JSON object, no prose and no code fences, exactly this shape:
-{"next_action": "<one concrete action to start now>", "success_condition": "<observable, verifiable done state>", "timebox_minutes": <integer, typically 15-50>}
+{"next_action": "<one concrete action to start now>", "success_condition": "<observable, verifiable done state>", "timebox_minutes": <integer, typically 15-50>, "allowed_window_classes": ["<app/window class that is on-task, e.g. code, firefox>"]}
 
 Rules:
 - next_action: a single concrete imperative action, doable now.
 - success_condition: observable and verifiable; how you'd know it is done.
 - timebox_minutes: a realistic integer number of minutes for the action.
+- allowed_window_classes: a short list of window/application class names that count as on-task for this action (lowercase, e.g. "code", "firefox"). May be empty.
 
 User intent: ` + intent
 }

internal/ai/proposal.go

@@ -16,6 +16,7 @@ type Proposal struct {
 	NextAction           string
 	SuccessCondition     string
 	TimeboxSecs          int64
+	AllowedWindowClasses []string
 }
 
 var (
@@ -64,6 +65,7 @@ type rawProposal struct {
 	NextAction           string   `json:"next_action"`
 	SuccessCondition     string   `json:"success_condition"`
 	TimeboxMinutes       int64    `json:"timebox_minutes"`
+	AllowedWindowClasses []string `json:"allowed_window_classes"`
 }
 
 // parseProposal extracts and validates a Proposal from raw CLI output.
@@ -91,5 +93,16 @@ func parseProposal(s string) (Proposal, error) {
 	if na == "" || sc == "" || raw.TimeboxMinutes <= 0 {
 		return Proposal{}, ErrInvalidProposal
 	}
-	return Proposal{NextAction: na, SuccessCondition: sc, TimeboxSecs: raw.TimeboxMinutes * 60}, nil
+	classes := make([]string, 0, len(raw.AllowedWindowClasses))
+	for _, cls := range raw.AllowedWindowClasses {
+		if t := strings.TrimSpace(cls); t != "" {
+			classes = append(classes, t)
+		}
+	}
+	return Proposal{
+		NextAction:           na,
+		SuccessCondition:     sc,
+		TimeboxSecs:          raw.TimeboxMinutes * 60,
+		AllowedWindowClasses: classes,
+	}, nil
 }

internal/ai/proposal_test.go

@@ -69,3 +69,23 @@ func TestParseProposal(t *testing.T) {
 		}
 	}
 }
+
+func TestParseProposalReadsAllowedClasses(t *testing.T) {
+	p, err := parseProposal(`{"next_action":"a","success_condition":"b","timebox_minutes":20,"allowed_window_classes":["code"," firefox ",""]}`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	if len(p.AllowedWindowClasses) != 2 || p.AllowedWindowClasses[0] != "code" || p.AllowedWindowClasses[1] != "firefox" {
+		t.Fatalf("classes wrong (blanks should drop, trim applied): %#v", p.AllowedWindowClasses)
+	}
+}
+
+func TestParseProposalAllowedClassesOptional(t *testing.T) {
+	p, err := parseProposal(`{"next_action":"a","success_condition":"b","timebox_minutes":20}`)
+	if err != nil {
+		t.Fatalf("parse: %v", err)
+	}
+	if len(p.AllowedWindowClasses) != 0 {
+		t.Fatalf("absent field should yield empty slice, got %#v", p.AllowedWindowClasses)
+	}
+}