feat(hyperguild): tier subcommand

Adds the tier subcommand to the hyperguild CLI. Reuses
internal/tier.Detect verbatim, sources probe URLs from
ANTHROPIC_PROBE_URL (default https://api.anthropic.com) and
LITELLM_BASE_URL (no default — empty triggers airplane).

Human-readable output by default; --json emits the same Info struct
as the supervisor's tier MCP returns. Tests cover all three tier
states via httptest fakes.

cmd/hyperguild/main.go

@@ -25,7 +25,7 @@ func notYet(ctx context.Context, args []string, stdin io.Reader, stdout, stderr
 
 func subcommands() map[string]subcommand {
 	return map[string]subcommand{
-		"tier":  notYet,
+		"tier":  runTier,
 		"brain": notYet,
 		"mode":  notYet,
 	}

cmd/hyperguild/main_test.go

@@ -35,8 +35,8 @@ func TestDispatch_UnknownSubcommand_ReturnsTwo(t *testing.T) {
 
 func TestDispatch_KnownSubcommand_RoutesAndReturnsExitCode(t *testing.T) {
 	var out, errBuf bytes.Buffer
-	code := dispatch(context.Background(), []string{"tier"}, strings.NewReader(""), &out, &errBuf)
-	// At Task 1 time, tier returns the not-implemented error → exit 1.
+	code := dispatch(context.Background(), []string{"brain"}, strings.NewReader(""), &out, &errBuf)
+	// At this point, brain still returns the not-implemented error → exit 1.
 	assert.Equal(t, 1, code)
 	assert.Contains(t, errBuf.String(), "not implemented")
 }

cmd/hyperguild/tier.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/mathiasbq/supervisor/internal/tier"
+)
+
+const defaultAnthropicProbe = "https://api.anthropic.com"
+
+func runTier(ctx context.Context, args []string, _ io.Reader, stdout, stderr io.Writer) error {
+	fs := flag.NewFlagSet("tier", flag.ContinueOnError)
+	fs.SetOutput(stderr)
+	asJSON := fs.Bool("json", false, "output JSON instead of human-readable")
+	if err := fs.Parse(args); err != nil {
+		return fmt.Errorf("parse flags: %w", err)
+	}
+
+	anthropicURL := os.Getenv("ANTHROPIC_PROBE_URL")
+	if anthropicURL == "" {
+		anthropicURL = defaultAnthropicProbe
+	}
+	liteLLMURL := os.Getenv("LITELLM_BASE_URL") // empty → tier falls through to airplane
+
+	info := tier.Detect(ctx, anthropicURL, liteLLMURL)
+
+	if *asJSON {
+		enc := json.NewEncoder(stdout)
+		enc.SetIndent("", "  ")
+		if err := enc.Encode(info); err != nil {
+			return fmt.Errorf("encode json: %w", err)
+		}
+		return nil
+	}
+	fmt.Fprintf(stdout, "tier %d (%s) managed_agents=%t\n", int(info.Tier), info.Label, info.ManagedAgents) //nolint:errcheck
+	return nil
+}

cmd/hyperguild/tier_test.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func okServer(t *testing.T) *httptest.Server {
+	t.Helper()
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+}
+
+func TestRunTier_Full_Human(t *testing.T) {
+	anthropic := okServer(t)
+	defer anthropic.Close()
+	litellm := okServer(t)
+	defer litellm.Close()
+
+	t.Setenv("ANTHROPIC_PROBE_URL", anthropic.URL)
+	t.Setenv("LITELLM_BASE_URL", litellm.URL)
+
+	var out, errBuf bytes.Buffer
+	err := runTier(context.Background(), []string{}, strings.NewReader(""), &out, &errBuf)
+	require.NoError(t, err)
+	assert.Contains(t, out.String(), "tier 1")
+	assert.Contains(t, out.String(), "full-online")
+	assert.Contains(t, out.String(), "managed_agents=true")
+}
+
+func TestRunTier_LANOnly_JSON(t *testing.T) {
+	litellm := okServer(t)
+	defer litellm.Close()
+
+	t.Setenv("ANTHROPIC_PROBE_URL", "http://127.0.0.1:1") // unreachable
+	t.Setenv("LITELLM_BASE_URL", litellm.URL)
+
+	var out, errBuf bytes.Buffer
+	err := runTier(context.Background(), []string{"--json"}, strings.NewReader(""), &out, &errBuf)
+	require.NoError(t, err)
+
+	var got struct {
+		Tier          int    `json:"tier"`
+		Label         string `json:"label"`
+		ManagedAgents bool   `json:"managed_agents"`
+	}
+	require.NoError(t, json.Unmarshal(out.Bytes(), &got))
+	assert.Equal(t, 2, got.Tier)
+	assert.Equal(t, "lan-only", got.Label)
+	assert.False(t, got.ManagedAgents)
+}
+
+func TestRunTier_Airplane_NoLiteLLMBaseURL(t *testing.T) {
+	t.Setenv("ANTHROPIC_PROBE_URL", "http://127.0.0.1:1")
+	t.Setenv("LITELLM_BASE_URL", "")
+
+	var out, errBuf bytes.Buffer
+	err := runTier(context.Background(), []string{}, strings.NewReader(""), &out, &errBuf)
+	require.NoError(t, err)
+	assert.Contains(t, out.String(), "tier 3")
+	assert.Contains(t, out.String(), "airplane")
+}
+
+func TestRunTier_UnknownFlag_ReturnsError(t *testing.T) {
+	var out, errBuf bytes.Buffer
+	err := runTier(context.Background(), []string{"--bogus"}, strings.NewReader(""), &out, &errBuf)
+	assert.Error(t, err)
+}