feat(event): emit typed error envelopes across the event domain (#1289)

Replace every command-facing error path in the event domain — the
consume/schema command layer, the +subscribe shortcut, EventKey
definitions, and the consume orchestration — with typed errs.*
envelopes, so consumers get stable type, subtype, param, hint, and
missing_scopes metadata for classification and recovery instead of
free-form message text.

- Input validation (--jq, --param, --output-dir, --filter, --route,
  unknown EventKey, EventKey params) reports validation /
  invalid_argument with the offending flag in param and an actionable
  hint.
- Scope preflight reports authorization / missing_scope with the
  machine-readable missing_scopes list; console-subscription and
  single-bus preconditions report failed_precondition with recovery
  hints.
- The consume API boundary passes already-typed errors through and
  classifies transport, non-JSON HTTP, and unparsable responses; the
  vc note-detail retry now matches the not-found code on typed errors
  (it silently never fired against the legacy envelope shape).
- Previously-bare failures exited 1 with a plain-text "Error:" line
  and now exit with their category code (validation 2, auth 3,
  network 4, internal 5) alongside the typed stderr envelope.
- forbidigo and errscontract guards now cover the event paths so
  regressions fail lint; AGENTS.md and the lark-event skill document
  the typed contract for agent consumers.

Validation: make unit-test (race) green; event unit and e2e suites
assert category/subtype/param/hint and cause preservation against the
real binary; errscontract and golangci lint clean.

cmd/event/bus.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/spf13/cobra"
 
+	"github.com/larksuite/cli/errs"
 	"github.com/larksuite/cli/internal/cmdutil"
 	"github.com/larksuite/cli/internal/core"
 	"github.com/larksuite/cli/internal/event"
@@ -38,7 +39,8 @@ func NewCmdBus(f *cmdutil.Factory) *cobra.Command {
 
 			logger, err := bus.SetupBusLogger(eventsDir)
 			if err != nil {
-				return err
+				return errs.NewInternalError(errs.SubtypeFileIO,
+					"set up bus logger: %s", err).WithCause(err)
 			}
 
 			tr := transport.New()
@@ -58,7 +60,14 @@ func NewCmdBus(f *cmdutil.Factory) *cobra.Command {
 				}
 			}()
 
-			return b.Run(ctx)
+			if err := b.Run(ctx); err != nil {
+				if _, ok := errs.ProblemOf(err); ok {
+					return err
+				}
+				return errs.NewInternalError(errs.SubtypeUnknown,
+					"event bus daemon exited: %s", err).WithCause(err)
+			}
+			return nil
 		},
 	}
 

cmd/event/bus_test.go

@@ -0,0 +1,45 @@
+// Copyright (c) 2026 Lark Technologies Pte. Ltd.
+// SPDX-License-Identifier: MIT
+
+package event
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/larksuite/cli/errs"
+	"github.com/larksuite/cli/internal/cmdutil"
+	"github.com/larksuite/cli/internal/core"
+)
+
+// The hidden `event _bus` daemon command must exit with a typed file_io error
+// when its log directory cannot be created (the error is only visible in the
+// forked process's captured stderr / bus.log).
+func TestBusCommandLoggerSetupFailureIsTypedFileIO(t *testing.T) {
+	dir := t.TempDir()
+	t.Setenv("LARKSUITE_CLI_CONFIG_DIR", dir)
+	// Block the events/ root with a regular file so MkdirAll fails.
+	if err := os.WriteFile(filepath.Join(dir, "events"), []byte("x"), 0600); err != nil {
+		t.Fatal(err)
+	}
+
+	f, _, _, _ := cmdutil.TestFactory(t, &core.CliConfig{
+		AppID: "cli_bus_test", AppSecret: "secret", Brand: core.BrandFeishu,
+	})
+	cmd := NewCmdBus(f)
+	cmd.SetArgs([]string{})
+
+	err := cmd.Execute()
+	if err == nil {
+		t.Fatal("expected logger setup error")
+	}
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
+	}
+	if p.Category != errs.CategoryInternal || p.Subtype != errs.SubtypeFileIO {
+		t.Errorf("problem = %s/%s, want %s/%s", p.Category, p.Subtype,
+			errs.CategoryInternal, errs.SubtypeFileIO)
+	}
+}

cmd/event/consume.go

@@ -16,6 +16,7 @@ import (
 
 	"github.com/spf13/cobra"
 
+	"github.com/larksuite/cli/errs"
 	"github.com/larksuite/cli/internal/appmeta"
 	"github.com/larksuite/cli/internal/auth"
 	"github.com/larksuite/cli/internal/cmdutil"
@@ -101,11 +102,10 @@ func runConsume(cmd *cobra.Command, f *cmdutil.Factory, eventKey string, o consu
 
 	if o.jqExpr != "" {
 		if err := output.ValidateJqExpression(o.jqExpr); err != nil {
-			return output.ErrWithHint(
-				output.ExitValidation, "validation",
-				err.Error(),
-				fmt.Sprintf("see `lark-cli event consume --help` EXAMPLES for common patterns, or `lark-cli event schema %s` for valid field paths", eventKey),
-			)
+			return errs.NewValidationError(errs.SubtypeInvalidArgument, "%s", err).
+				WithParam("--jq").
+				WithCause(err).
+				WithHint("see `lark-cli event consume --help` EXAMPLES for common patterns, or `lark-cli event schema %s` for valid field paths", eventKey)
 		}
 	}
 
@@ -261,12 +261,12 @@ func preflightScopes(ctx context.Context, pf *preflightCtx) error {
 	if len(missing) == 0 {
 		return nil
 	}
-	return output.ErrWithHint(
-		output.ExitAuth, "auth",
-		fmt.Sprintf("missing required scopes for EventKey %s (as %s): %s",
-			pf.eventKey, pf.identity, strings.Join(missing, ", ")),
-		scopeRemediationHint(pf.identity, missing, pf.appID, pf.brand),
-	)
+	return errs.NewPermissionError(errs.SubtypeMissingScope,
+		"missing required scopes for EventKey %s (as %s): %s",
+		pf.eventKey, pf.identity, strings.Join(missing, ", ")).
+		WithIdentity(string(pf.identity)).
+		WithMissingScopes(missing...).
+		WithHint("%s", scopeRemediationHint(pf.identity, missing, pf.appID, pf.brand))
 }
 
 // scopeRemediationHint returns an identity-appropriate fix for missing scopes.
@@ -301,23 +301,27 @@ func preflightEventTypes(pf *preflightCtx) error {
 	if len(missing) == 0 {
 		return nil
 	}
-	return output.ErrWithHint(
-		output.ExitValidation, "validation",
-		fmt.Sprintf("EventKey %s requires event types not subscribed in console: %s",
-			pf.keyDef.Key, strings.Join(missing, ", ")),
-		fmt.Sprintf("subscribe these events and publish a new app version at: %s",
-			consoleEventSubscriptionURL(pf.brand, pf.appID)),
-	)
+	return errs.NewValidationError(errs.SubtypeFailedPrecondition,
+		"EventKey %s requires event types not subscribed in console: %s",
+		pf.keyDef.Key, strings.Join(missing, ", ")).
+		WithHint("subscribe these events and publish a new app version at: %s",
+			consoleEventSubscriptionURL(pf.brand, pf.appID))
 }
 
 // sanitizeOutputDir rejects absolute/parent-escaping paths and ~ (SafeOutputPath treats it as a literal dir name).
 func sanitizeOutputDir(dir string) (string, error) {
 	if strings.HasPrefix(dir, "~") {
-		return "", output.ErrValidation("%s; use a relative path like ./output instead", errOutputDirTilde)
+		return "", errs.NewValidationError(errs.SubtypeInvalidArgument,
+			"%s; use a relative path like ./output instead", errOutputDirTilde).
+			WithParam("--output-dir").
+			WithCause(errOutputDirTilde)
 	}
 	safe, err := validate.SafeOutputPath(dir)
 	if err != nil {
-		return "", output.ErrValidation("%s %q: %s", errOutputDirUnsafe, dir, err)
+		return "", errs.NewValidationError(errs.SubtypeInvalidArgument,
+			"%s %q: %s", errOutputDirUnsafe, dir, err).
+			WithParam("--output-dir").
+			WithCause(errOutputDirUnsafe)
 	}
 	return safe, nil
 }
@@ -329,18 +333,21 @@ func resolveTenantToken(ctx context.Context, f *cmdutil.Factory, appID string) (
 	}
 	result, err := f.Credential.ResolveToken(ctx, credential.NewTokenSpec(core.AsBot, appID))
 	if err != nil {
-		return "", output.ErrAuth("resolve tenant access token: %s", err)
+		if _, ok := errs.ProblemOf(err); ok {
+			return "", err
+		}
+		return "", errs.NewAuthenticationError(errs.SubtypeTokenMissing,
+			"resolve tenant access token: %s", err).WithCause(err)
 	}
 	if result == nil || result.Token == "" {
-		return "", output.ErrWithHint(
-			output.ExitAuth, "auth",
-			fmt.Sprintf("no tenant access token available for app %s", appID),
-			"Check that app_secret is configured (lark-cli config show) and try 'lark-cli auth login'.",
-		)
+		return "", errs.NewAuthenticationError(errs.SubtypeTokenMissing,
+			"no tenant access token available for app %s", appID).
+			WithHint("Check that app_secret is configured (lark-cli config show) and try 'lark-cli auth login'.")
 	}
 	return result.Token, nil
 }
 
+// Sentinels for errors.Is checks; call sites wrap them as typed ValidationError causes.
 var (
 	errInvalidParamFormat = errors.New("invalid --param format")
 	errOutputDirTilde     = errors.New("--output-dir does not support ~ expansion")
@@ -352,7 +359,10 @@ func parseParams(raw []string) (map[string]string, error) {
 	for _, kv := range raw {
 		k, v, ok := strings.Cut(kv, "=")
 		if !ok || k == "" {
-			return nil, output.ErrValidation("%s %q: expected key=value", errInvalidParamFormat, kv)
+			return nil, errs.NewValidationError(errs.SubtypeInvalidArgument,
+				"%s %q: expected key=value", errInvalidParamFormat, kv).
+				WithParam("--param").
+				WithCause(errInvalidParamFormat)
 		}
 		m[k] = v
 	}

cmd/event/consume_test.go

@@ -4,9 +4,14 @@
 package event
 
 import (
+	"context"
 	"errors"
 	"strings"
 	"testing"
+
+	"github.com/larksuite/cli/errs"
+	"github.com/larksuite/cli/internal/cmdutil"
+	"github.com/larksuite/cli/internal/credential"
 )
 
 func TestParseParams(t *testing.T) {
@@ -73,6 +78,7 @@ func TestParseParams(t *testing.T) {
 				if tc.wantEcho != "" && !strings.Contains(err.Error(), tc.wantEcho) {
 					t.Errorf("err %q should echo %q so user sees the bad input", err.Error(), tc.wantEcho)
 				}
+				assertInvalidArgumentParam(t, err, "--param")
 				return
 			}
 			if err != nil {
@@ -90,6 +96,77 @@ func TestParseParams(t *testing.T) {
 	}
 }
 
+// emptyTokenResolver resolves to a result that carries no token.
+type emptyTokenResolver struct{}
+
+func (emptyTokenResolver) ResolveToken(_ context.Context, _ credential.TokenSpec) (*credential.TokenResult, error) {
+	return &credential.TokenResult{}, nil
+}
+
+// failingTokenResolver fails outright with an untyped error.
+type failingTokenResolver struct{}
+
+func (failingTokenResolver) ResolveToken(_ context.Context, _ credential.TokenSpec) (*credential.TokenResult, error) {
+	return nil, errors.New("backend unavailable")
+}
+
+func factoryWithResolver(r credential.DefaultTokenResolver) *cmdutil.Factory {
+	return &cmdutil.Factory{Credential: credential.NewCredentialProvider(nil, nil, r, nil)}
+}
+
+func TestResolveTenantToken_EmptyTokenResult(t *testing.T) {
+	_, err := resolveTenantToken(context.Background(), factoryWithResolver(emptyTokenResolver{}), "cli_x")
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
+	}
+	if p.Category != errs.CategoryAuthentication || p.Subtype != errs.SubtypeTokenMissing {
+		t.Errorf("problem = %s/%s, want %s/%s", p.Category, p.Subtype,
+			errs.CategoryAuthentication, errs.SubtypeTokenMissing)
+	}
+	var malformed *credential.MalformedTokenResultError
+	if !errors.As(err, &malformed) {
+		t.Error("empty-token failure should preserve the credential-layer cause")
+	}
+}
+
+func TestResolveTenantToken_ResolverFailure(t *testing.T) {
+	_, err := resolveTenantToken(context.Background(), factoryWithResolver(failingTokenResolver{}), "cli_x")
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
+	}
+	if p.Category != errs.CategoryAuthentication || p.Subtype != errs.SubtypeTokenMissing {
+		t.Errorf("problem = %s/%s, want %s/%s", p.Category, p.Subtype,
+			errs.CategoryAuthentication, errs.SubtypeTokenMissing)
+	}
+	if errors.Unwrap(err) == nil {
+		t.Error("resolver failure should preserve its cause")
+	}
+}
+
+// assertInvalidArgumentParam verifies err is a typed validation error with
+// subtype invalid_argument naming the given flag in its param field.
+func assertInvalidArgumentParam(t *testing.T, err error, param string) {
+	t.Helper()
+	var ve *errs.ValidationError
+	if !errors.As(err, &ve) {
+		t.Fatalf("expected *errs.ValidationError, got %T: %v", err, err)
+	}
+	if ve.Subtype != errs.SubtypeInvalidArgument {
+		t.Errorf("subtype = %s, want %s", ve.Subtype, errs.SubtypeInvalidArgument)
+	}
+	if ve.Param != param {
+		t.Errorf("param = %q, want %q", ve.Param, param)
+	}
+}
+
 func TestSanitizeOutputDir(t *testing.T) {
 	cases := []struct {
 		name       string
@@ -130,6 +207,7 @@ func TestSanitizeOutputDir(t *testing.T) {
 				if !errors.Is(err, tc.wantSentry) {
 					t.Fatalf("want errors.Is(err, %v), got %q", tc.wantSentry, err.Error())
 				}
+				assertInvalidArgumentParam(t, err, "--output-dir")
 				return
 			}
 			if err != nil {

cmd/event/preflight_test.go

@@ -8,10 +8,10 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/larksuite/cli/errs"
 	"github.com/larksuite/cli/internal/appmeta"
 	"github.com/larksuite/cli/internal/core"
 	eventlib "github.com/larksuite/cli/internal/event"
-	"github.com/larksuite/cli/internal/output"
 )
 
 func newPreflightCtx(appID string, brand core.LarkBrand, identity core.Identity, keyDef *eventlib.KeyDefinition, appVer *appmeta.AppVersion) *preflightCtx {
@@ -89,19 +89,17 @@ func TestPreflightEventTypes_MissingBlocks(t *testing.T) {
 	if !strings.Contains(err.Error(), "mail.user_mailbox.event.message_read_v1") {
 		t.Errorf("error should name the missing event type, got: %v", err)
 	}
-	var exit *output.ExitError
-	if !errors.As(err, &exit) {
-		t.Fatalf("expected output.ExitError, got %T: %v", err, err)
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
 	}
-	if exit.Code != output.ExitValidation {
-		t.Errorf("ExitCode = %d, want ExitValidation (%d)", exit.Code, output.ExitValidation)
-	}
-	if exit.Detail == nil {
-		t.Fatal("expected Detail with hint")
+	if p.Category != errs.CategoryValidation || p.Subtype != errs.SubtypeFailedPrecondition {
+		t.Errorf("problem = %s/%s, want %s/%s", p.Category, p.Subtype,
+			errs.CategoryValidation, errs.SubtypeFailedPrecondition)
 	}
 	wantURL := "https://open.feishu.cn/app/cli_XXXXXXXXXXXXXXXX/event"
-	if !strings.Contains(exit.Detail.Hint, wantURL) {
-		t.Errorf("hint missing subscription URL %q\ngot: %s", wantURL, exit.Detail.Hint)
+	if !strings.Contains(p.Hint, wantURL) {
+		t.Errorf("hint missing subscription URL %q\ngot: %s", wantURL, p.Hint)
 	}
 }
 
@@ -145,17 +143,19 @@ func TestPreflightScopes_Bot_MissingBlocks(t *testing.T) {
 	if !strings.Contains(err.Error(), "im:message.group_at_msg") {
 		t.Errorf("error should name missing scope, got: %v", err)
 	}
-	var exit *output.ExitError
-	if !errors.As(err, &exit) {
-		t.Fatalf("expected output.ExitError, got %T: %v", err, err)
+	var permErr *errs.PermissionError
+	if !errors.As(err, &permErr) {
+		t.Fatalf("expected *errs.PermissionError, got %T: %v", err, err)
 	}
-	if exit.Code != output.ExitAuth {
-		t.Errorf("ExitCode = %d, want ExitAuth (%d)", exit.Code, output.ExitAuth)
+	if permErr.Category != errs.CategoryAuthorization || permErr.Subtype != errs.SubtypeMissingScope {
+		t.Errorf("problem = %s/%s, want %s/%s", permErr.Category, permErr.Subtype,
+			errs.CategoryAuthorization, errs.SubtypeMissingScope)
 	}
-	if exit.Detail == nil {
-		t.Fatal("expected Detail with hint, got nil Detail")
+	wantMissing := []string{"im:message.group_at_msg"}
+	if len(permErr.MissingScopes) != 1 || permErr.MissingScopes[0] != wantMissing[0] {
+		t.Errorf("MissingScopes = %v, want %v", permErr.MissingScopes, wantMissing)
 	}
-	hint := exit.Detail.Hint
+	hint := permErr.Hint
 	wantSubstrings := []string{
 		"https://open.feishu.cn/app/cli_x/auth?q=",
 		"im:message.group_at_msg",

cmd/event/runtime.go

@@ -6,8 +6,8 @@ package event
 import (
 	"context"
 	"encoding/json"
-	"fmt"
 
+	"github.com/larksuite/cli/errs"
 	"github.com/larksuite/cli/internal/client"
 	"github.com/larksuite/cli/internal/core"
 )
@@ -26,7 +26,11 @@ func (r *consumeRuntime) CallAPI(ctx context.Context, method, path string, body
 		As:     r.accessIdentity,
 	})
 	if err != nil {
-		return nil, err
+		if _, ok := errs.ProblemOf(err); ok {
+			return nil, err
+		}
+		return nil, errs.NewNetworkError(errs.SubtypeNetworkTransport,
+			"api %s %s: %s", method, path, err).WithCause(err)
 	}
 	// Non-JSON HTTP errors (gateway text/plain 404 etc.) skip OAPI envelope parsing.
 	ct := resp.Header.Get("Content-Type")
@@ -36,11 +40,20 @@ func (r *consumeRuntime) CallAPI(ctx context.Context, method, path string, body
 		if len(body) > maxBodyEcho {
 			body = body[:maxBodyEcho] + "…(truncated)"
 		}
-		return nil, fmt.Errorf("api %s %s returned %d: %s", method, path, resp.StatusCode, body)
+		if resp.StatusCode >= 500 {
+			return nil, errs.NewNetworkError(errs.SubtypeNetworkServer,
+				"api %s %s returned %d: %s", method, path, resp.StatusCode, body).WithRetryable()
+		}
+		return nil, errs.NewInternalError(errs.SubtypeInvalidResponse,
+			"api %s %s returned %d: %s", method, path, resp.StatusCode, body)
 	}
 	result, err := client.ParseJSONResponse(resp)
 	if err != nil {
-		return nil, err
+		if _, ok := errs.ProblemOf(err); ok {
+			return nil, err
+		}
+		return nil, errs.NewInternalError(errs.SubtypeInvalidResponse,
+			"api %s %s: %s", method, path, err).WithCause(err)
 	}
 	if apiErr := r.client.CheckResponse(result, r.accessIdentity); apiErr != nil {
 		return json.RawMessage(resp.RawBody), apiErr

cmd/event/runtime_test.go

@@ -0,0 +1,147 @@
+// Copyright (c) 2026 Lark Technologies Pte. Ltd.
+// SPDX-License-Identifier: MIT
+
+package event
+
+import (
+	"context"
+	"errors"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+
+	lark "github.com/larksuite/oapi-sdk-go/v3"
+	larkcore "github.com/larksuite/oapi-sdk-go/v3/core"
+
+	"github.com/larksuite/cli/errs"
+	"github.com/larksuite/cli/internal/client"
+	"github.com/larksuite/cli/internal/core"
+	"github.com/larksuite/cli/internal/credential"
+)
+
+// staticTokenResolver always returns a fixed token without any HTTP calls.
+type staticTokenResolver struct{}
+
+func (s *staticTokenResolver) ResolveToken(_ context.Context, _ credential.TokenSpec) (*credential.TokenResult, error) {
+	return &credential.TokenResult{Token: "test-token"}, nil
+}
+
+// stubRoundTripper intercepts every outgoing request with a canned response.
+type stubRoundTripper struct {
+	respond func(*http.Request) (*http.Response, error)
+}
+
+func (s stubRoundTripper) RoundTrip(r *http.Request) (*http.Response, error) { return s.respond(r) }
+
+func newTestConsumeRuntime(rt http.RoundTripper) *consumeRuntime {
+	sdk := lark.NewClient("test-app", "test-secret",
+		lark.WithEnableTokenCache(false),
+		lark.WithLogLevel(larkcore.LogLevelError),
+		lark.WithHttpClient(&http.Client{Transport: rt}),
+	)
+	return &consumeRuntime{
+		client: &client.APIClient{
+			SDK:        sdk,
+			ErrOut:     io.Discard,
+			Credential: credential.NewCredentialProvider(nil, nil, &staticTokenResolver{}, nil),
+			Config:     &core.CliConfig{AppID: "test-app", AppSecret: "test-secret", Brand: core.BrandFeishu},
+		},
+		accessIdentity: core.AsBot,
+	}
+}
+
+func stubResponse(status int, contentType, body string) func(*http.Request) (*http.Response, error) {
+	return func(r *http.Request) (*http.Response, error) {
+		return &http.Response{
+			StatusCode: status,
+			Header:     http.Header{"Content-Type": []string{contentType}},
+			Body:       io.NopCloser(strings.NewReader(body)),
+			Request:    r,
+		}, nil
+	}
+}
+
+func requireCallAPIProblem(t *testing.T, err error, category errs.Category, subtype errs.Subtype) {
+	t.Helper()
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
+	}
+	if p.Category != category || p.Subtype != subtype {
+		t.Fatalf("problem = %s/%s, want %s/%s", p.Category, p.Subtype, category, subtype)
+	}
+}
+
+func TestConsumeRuntimeCallAPI_NonJSONHTTPError(t *testing.T) {
+	r := newTestConsumeRuntime(stubRoundTripper{respond: stubResponse(http.StatusNotFound, "text/plain", "gone")})
+	_, err := r.CallAPI(context.Background(), "GET", "/open-apis/event/v1/connection", nil)
+	requireCallAPIProblem(t, err, errs.CategoryInternal, errs.SubtypeInvalidResponse)
+	if !strings.Contains(err.Error(), "returned 404") {
+		t.Errorf("error should echo the HTTP status, got: %v", err)
+	}
+}
+
+func TestConsumeRuntimeCallAPI_NonJSONHTTPErrorTruncatesLongBody(t *testing.T) {
+	long := strings.Repeat("x", 300)
+	r := newTestConsumeRuntime(stubRoundTripper{respond: stubResponse(http.StatusBadGateway, "text/html", long)})
+	_, err := r.CallAPI(context.Background(), "GET", "/open-apis/event/v1/connection", nil)
+	requireCallAPIProblem(t, err, errs.CategoryNetwork, errs.SubtypeNetworkServer)
+	p, _ := errs.ProblemOf(err)
+	if !p.Retryable {
+		t.Fatal("5xx non-JSON response should be marked retryable")
+	}
+	if !strings.Contains(err.Error(), "…(truncated)") {
+		t.Errorf("long body should be truncated in the message, got: %v", err)
+	}
+}
+
+func TestConsumeRuntimeCallAPI_UnparsableJSONBody(t *testing.T) {
+	r := newTestConsumeRuntime(stubRoundTripper{respond: stubResponse(http.StatusOK, "application/json", "{not json")})
+	_, err := r.CallAPI(context.Background(), "GET", "/open-apis/event/v1/connection", nil)
+	requireCallAPIProblem(t, err, errs.CategoryInternal, errs.SubtypeInvalidResponse)
+}
+
+func TestConsumeRuntimeCallAPI_TransportFailure(t *testing.T) {
+	r := newTestConsumeRuntime(stubRoundTripper{respond: func(*http.Request) (*http.Response, error) {
+		return nil, errors.New("connection refused")
+	}})
+	_, err := r.CallAPI(context.Background(), "GET", "/open-apis/event/v1/connection", nil)
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
+	}
+	if p.Category != errs.CategoryNetwork {
+		t.Fatalf("category = %s, want %s", p.Category, errs.CategoryNetwork)
+	}
+}
+
+func TestConsumeRuntimeCallAPI_EnvelopeErrorIsTyped(t *testing.T) {
+	r := newTestConsumeRuntime(stubRoundTripper{respond: stubResponse(http.StatusOK, "application/json",
+		`{"code":99991663,"msg":"app not found"}`)})
+	_, err := r.CallAPI(context.Background(), "GET", "/open-apis/event/v1/connection", nil)
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	if _, ok := errs.ProblemOf(err); !ok {
+		t.Fatalf("envelope error should be typed via BuildAPIError, got %T: %v", err, err)
+	}
+}
+
+func TestConsumeRuntimeCallAPI_Success(t *testing.T) {
+	r := newTestConsumeRuntime(stubRoundTripper{respond: stubResponse(http.StatusOK, "application/json",
+		`{"code":0,"data":{"ok":true}}`)})
+	raw, err := r.CallAPI(context.Background(), "GET", "/open-apis/event/v1/connection", nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !strings.Contains(string(raw), `"code":0`) {
+		t.Errorf("raw body should pass through, got: %s", raw)
+	}
+}

cmd/event/schema.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/spf13/cobra"
 
+	"github.com/larksuite/cli/errs"
 	"github.com/larksuite/cli/internal/cmdutil"
 	eventlib "github.com/larksuite/cli/internal/event"
 	"github.com/larksuite/cli/internal/event/schemas"
@@ -39,12 +40,14 @@ func resolveSchemaJSON(def *eventlib.KeyDefinition) (json.RawMessage, []string,
 	if len(def.Schema.FieldOverrides) > 0 {
 		var parsed map[string]interface{}
 		if err := json.Unmarshal(base, &parsed); err != nil {
-			return nil, nil, err
+			return nil, nil, errs.NewInternalError(errs.SubtypeUnknown,
+				"parse base schema for field overrides: %s", err).WithCause(err)
 		}
 		orphans := schemas.ApplyFieldOverrides(parsed, def.Schema.FieldOverrides)
 		out, err := json.Marshal(parsed)
 		if err != nil {
-			return nil, nil, err
+			return nil, nil, errs.NewInternalError(errs.SubtypeUnknown,
+				"serialize schema with field overrides: %s", err).WithCause(err)
 		}
 		return out, orphans, nil
 	}
@@ -73,7 +76,7 @@ func renderSpec(s *eventlib.SchemaSpec) (json.RawMessage, error) {
 		copy(buf, s.Raw)
 		return buf, nil
 	}
-	return nil, fmt.Errorf("schemaSpec has neither Type nor Raw")
+	return nil, errs.NewInternalError(errs.SubtypeUnknown, "schemaSpec has neither Type nor Raw")
 }
 
 func NewCmdSchema(f *cmdutil.Factory) *cobra.Command {
@@ -165,7 +168,7 @@ func runSchema(f *cmdutil.Factory, key string, asJSON bool) error {
 
 	resolved, _, err := resolveSchemaJSON(def)
 	if err != nil {
-		return output.Errorf(output.ExitInternal, "internal", "resolve schema: %v", err)
+		return err
 	}
 	if resolved != nil {
 		fmt.Fprintf(out, "\nOutput Schema:\n")

cmd/event/schema_test.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/larksuite/cli/errs"
 	"github.com/larksuite/cli/internal/cmdutil"
 	"github.com/larksuite/cli/internal/core"
 	eventlib "github.com/larksuite/cli/internal/event"
@@ -129,3 +130,38 @@ func TestResolveSchemaJSON_CustomWithOverlay(t *testing.T) {
 		t.Errorf("overlay format = %v, want open_id", got)
 	}
 }
+
+func TestRenderSpec_EmptySpecIsTypedInternalError(t *testing.T) {
+	_, err := renderSpec(&eventlib.SchemaSpec{})
+	if err == nil {
+		t.Fatal("expected error for spec with neither Type nor Raw")
+	}
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
+	}
+	if p.Category != errs.CategoryInternal {
+		t.Errorf("category = %s, want %s", p.Category, errs.CategoryInternal)
+	}
+}
+
+func TestResolveSchemaJSON_InvalidBaseWithOverridesIsTypedInternalError(t *testing.T) {
+	def := &eventlib.KeyDefinition{
+		Key: "synthetic.invalid.base",
+		Schema: eventlib.SchemaDef{
+			Custom:         &eventlib.SchemaSpec{Raw: json.RawMessage("{not json")},
+			FieldOverrides: map[string]schemas.FieldMeta{"x": {}},
+		},
+	}
+	_, _, err := resolveSchemaJSON(def)
+	if err == nil {
+		t.Fatal("expected error for unparsable base schema")
+	}
+	p, ok := errs.ProblemOf(err)
+	if !ok {
+		t.Fatalf("expected typed errs error, got %T: %v", err, err)
+	}
+	if p.Category != errs.CategoryInternal {
+		t.Errorf("category = %s, want %s", p.Category, errs.CategoryInternal)
+	}
+}

cmd/event/suggestions.go

@@ -8,8 +8,8 @@ import (
 	"sort"
 	"strings"
 
+	"github.com/larksuite/cli/errs"
 	eventlib "github.com/larksuite/cli/internal/event"
-	"github.com/larksuite/cli/internal/output"
 	"github.com/larksuite/cli/internal/suggest"
 )
 
@@ -64,9 +64,6 @@ func unknownEventKeyErr(key string) error {
 	if guesses := suggestEventKeys(key); len(guesses) > 0 {
 		msg += " — did you mean " + formatSuggestions(guesses) + "?"
 	}
-	return output.ErrWithHint(
-		output.ExitValidation, "validation",
-		msg,
-		"Run 'lark-cli event list' to see available keys.",
-	)
+	return errs.NewValidationError(errs.SubtypeInvalidArgument, "%s", msg).
+		WithHint("Run 'lark-cli event list' to see available keys.")
 }