internal/runtime/executor/antigravity_executor.go

// Package executor provides runtime execution capabilities for various AI service providers.
// This file implements the Antigravity executor that proxies requests to the antigravity
// upstream using OAuth credentials.
package executor

import (
	"bufio"
	"bytes"
	"context"
	"crypto/sha256"
	"crypto/tls"
	"encoding/binary"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"math/rand"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"sync"
	"time"

	"github.com/google/uuid"
	"github.com/router-for-me/CLIProxyAPI/v6/internal/cache"
	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
	"github.com/router-for-me/CLIProxyAPI/v6/internal/misc"
	"github.com/router-for-me/CLIProxyAPI/v6/internal/registry"
	"github.com/router-for-me/CLIProxyAPI/v6/internal/runtime/executor/helps"
	"github.com/router-for-me/CLIProxyAPI/v6/internal/thinking"
	antigravityclaude "github.com/router-for-me/CLIProxyAPI/v6/internal/translator/antigravity/claude"
	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"
	sdkAuth "github.com/router-for-me/CLIProxyAPI/v6/sdk/auth"
	cliproxyauth "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
	log "github.com/sirupsen/logrus"
	"github.com/tidwall/gjson"
	"github.com/tidwall/sjson"
)

const (
	antigravityBaseURLDaily                = "https://daily-cloudcode-pa.googleapis.com"
	antigravitySandboxBaseURLDaily         = "https://daily-cloudcode-pa.sandbox.googleapis.com"
	antigravityBaseURLProd                 = "https://cloudcode-pa.googleapis.com"
	antigravityCountTokensPath             = "/v1internal:countTokens"
	antigravityStreamPath                  = "/v1internal:streamGenerateContent"
	antigravityGeneratePath                = "/v1internal:generateContent"
	antigravityClientID                    = "1071006060591-tmhssin2h21lcre235vtolojh4g403ep.apps.googleusercontent.com"
	antigravityClientSecret                = "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"
	defaultAntigravityAgent                = "antigravity/1.21.9 darwin/arm64" // fallback only; overridden at runtime by misc.AntigravityUserAgent()
	antigravityAuthType                    = "antigravity"
	refreshSkew                            = 3000 * time.Second
	antigravityCreditsHintRefreshInterval  = 10 * time.Minute
	antigravityCreditsHintRefreshTimeout   = 5 * time.Second
	antigravityShortQuotaCooldownThreshold = 5 * time.Minute
	antigravityInstantRetryThreshold       = 3 * time.Second
	// systemInstruction              = "You are Antigravity, a powerful agentic AI coding assistant designed by the Google Deepmind team working on Advanced Agentic Coding.You are pair programming with a USER to solve their coding task. The task may require creating a new codebase, modifying or debugging an existing codebase, or simply answering a question.**Absolute paths only****Proactiveness**"
)

type antigravity429Category string

type antigravityCreditsFailureState struct {
	PermanentlyDisabled      bool
	ExplicitBalanceExhausted bool
}

type antigravity429DecisionKind string

const (
	antigravity429Unknown                         antigravity429Category     = "unknown"
	antigravity429RateLimited                     antigravity429Category     = "rate_limited"
	antigravity429QuotaExhausted                  antigravity429Category     = "quota_exhausted"
	antigravity429SoftRateLimit                   antigravity429Category     = "soft_rate_limit"
	antigravity429DecisionSoftRetry               antigravity429DecisionKind = "soft_retry"
	antigravity429DecisionInstantRetrySameAuth    antigravity429DecisionKind = "instant_retry_same_auth"
	antigravity429DecisionShortCooldownSwitchAuth antigravity429DecisionKind = "short_cooldown_switch_auth"
	antigravity429DecisionFullQuotaExhausted      antigravity429DecisionKind = "full_quota_exhausted"
)

type antigravity429Decision struct {
	kind       antigravity429DecisionKind
	retryAfter *time.Duration
	reason     string
}

var (
	randSource                        = rand.New(rand.NewSource(time.Now().UnixNano()))
	randSourceMutex                   sync.Mutex
	antigravityCreditsFailureByAuth   sync.Map
	antigravityShortCooldownByAuth    sync.Map
	antigravityCreditsBalanceByAuth   sync.Map // auth.ID → antigravityCreditsBalance
	antigravityCreditsHintRefreshByID sync.Map // auth.ID → *antigravityCreditsHintRefreshState
	antigravityQuotaExhaustedKeywords = []string{
		"quota_exhausted",
		"quota exhausted",
	}
)

type antigravityCreditsBalance struct {
	CreditAmount    float64
	MinCreditAmount float64
	PaidTierID      string
	Known           bool
}

type antigravityCreditsHintRefreshState struct {
	mu          sync.Mutex
	lastAttempt time.Time
}

func antigravityAuthHasCredits(auth *cliproxyauth.Auth) bool {
	if auth == nil || strings.TrimSpace(auth.ID) == "" {
		return false
	}
	if hint, ok := cliproxyauth.GetAntigravityCreditsHint(auth.ID); ok && hint.Known {
		return hint.Available
	}
	val, ok := antigravityCreditsBalanceByAuth.Load(strings.TrimSpace(auth.ID))
	if !ok {
		return true // optimistic: assume credits available when balance unknown
	}
	bal, valid := val.(antigravityCreditsBalance)
	if !valid {
		antigravityCreditsBalanceByAuth.Delete(strings.TrimSpace(auth.ID))
		return false
	}
	if !bal.Known {
		return false
	}
	available := bal.CreditAmount >= bal.MinCreditAmount
	cliproxyauth.SetAntigravityCreditsHint(strings.TrimSpace(auth.ID), cliproxyauth.AntigravityCreditsHint{
		Known:           true,
		Available:       available,
		CreditAmount:    bal.CreditAmount,
		MinCreditAmount: bal.MinCreditAmount,
		PaidTierID:      bal.PaidTierID,
		UpdatedAt:       time.Now(),
	})
	return available
}

// parseMetaFloat extracts a float64 from auth.Metadata (handles string and numeric types).
func parseMetaFloat(metadata map[string]any, key string) (float64, bool) {
	v, ok := metadata[key]
	if !ok {
		return 0, false
	}
	switch typed := v.(type) {
	case float64:
		return typed, true
	case int:
		return float64(typed), true
	case int64:
		return float64(typed), true
	case uint64:
		return float64(typed), true
	case json.Number:
		if f, err := typed.Float64(); err == nil {
			return f, true
		}
	case string:
		if f, err := strconv.ParseFloat(strings.TrimSpace(typed), 64); err == nil {
			return f, true
		}
	}
	return 0, false
}

// AntigravityExecutor proxies requests to the antigravity upstream.
type AntigravityExecutor struct {
	cfg *config.Config
}

// NewAntigravityExecutor creates a new Antigravity executor instance.
//
// Parameters:
//   - cfg: The application configuration
//
// Returns:
//   - *AntigravityExecutor: A new Antigravity executor instance
func NewAntigravityExecutor(cfg *config.Config) *AntigravityExecutor {
	return &AntigravityExecutor{cfg: cfg}
}

// antigravityTransport is a singleton HTTP/1.1 transport shared by all Antigravity requests.
// It is initialized once via antigravityTransportOnce to avoid leaking a new connection pool
// (and the goroutines managing it) on every request.
var (
	antigravityTransport     *http.Transport
	antigravityTransportOnce sync.Once
)

func cloneTransportWithHTTP11(base *http.Transport) *http.Transport {
	if base == nil {
		return nil
	}

	clone := base.Clone()
	clone.ForceAttemptHTTP2 = false
	// Wipe TLSNextProto to prevent implicit HTTP/2 upgrade.
	clone.TLSNextProto = make(map[string]func(authority string, c *tls.Conn) http.RoundTripper)
	if clone.TLSClientConfig == nil {
		clone.TLSClientConfig = &tls.Config{}
	} else {
		clone.TLSClientConfig = clone.TLSClientConfig.Clone()
	}
	// Actively advertise only HTTP/1.1 in the ALPN handshake.
	clone.TLSClientConfig.NextProtos = []string{"http/1.1"}
	return clone
}

// initAntigravityTransport creates the shared HTTP/1.1 transport exactly once.
func initAntigravityTransport() {
	base, ok := http.DefaultTransport.(*http.Transport)
	if !ok {
		base = &http.Transport{}
	}
	antigravityTransport = cloneTransportWithHTTP11(base)
}

// newAntigravityHTTPClient creates an HTTP client specifically for Antigravity,
// enforcing HTTP/1.1 by disabling HTTP/2 to perfectly mimic Node.js https defaults.
// The underlying Transport is a singleton to avoid leaking connection pools.
func newAntigravityHTTPClient(ctx context.Context, cfg *config.Config, auth *cliproxyauth.Auth, timeout time.Duration) *http.Client {
	antigravityTransportOnce.Do(initAntigravityTransport)

	client := helps.NewProxyAwareHTTPClient(ctx, cfg, auth, timeout)
	// If no transport is set, use the shared HTTP/1.1 transport.
	if client.Transport == nil {
		client.Transport = antigravityTransport
		return client
	}

	// Preserve proxy settings from proxy-aware transports while forcing HTTP/1.1.
	if transport, ok := client.Transport.(*http.Transport); ok {
		client.Transport = cloneTransportWithHTTP11(transport)
	}
	return client
}

func validateAntigravityRequestSignatures(from sdktranslator.Format, rawJSON []byte) ([]byte, error) {
	if from.String() != "claude" {
		return rawJSON, nil
	}
	// Always strip thinking blocks with invalid signatures (empty or non-Claude-format).
	rawJSON = antigravityclaude.StripEmptySignatureThinkingBlocks(rawJSON)
	if cache.SignatureCacheEnabled() {
		return rawJSON, nil
	}
	if !cache.SignatureBypassStrictMode() {
		// Non-strict bypass: let the translator handle invalid signatures
		// by dropping unsigned thinking blocks silently (no 400).
		return rawJSON, nil
	}
	if err := antigravityclaude.ValidateClaudeBypassSignatures(rawJSON); err != nil {
		return rawJSON, statusErr{code: http.StatusBadRequest, msg: err.Error()}
	}
	return rawJSON, nil
}

// Identifier returns the executor identifier.
func (e *AntigravityExecutor) Identifier() string { return antigravityAuthType }

// PrepareRequest injects Antigravity credentials into the outgoing HTTP request.
func (e *AntigravityExecutor) PrepareRequest(req *http.Request, auth *cliproxyauth.Auth) error {
	if req == nil {
		return nil
	}
	token, _, errToken := e.ensureAccessToken(req.Context(), auth)
	if errToken != nil {
		return errToken
	}
	if strings.TrimSpace(token) == "" {
		return statusErr{code: http.StatusUnauthorized, msg: "missing access token"}
	}
	req.Header.Set("Authorization", "Bearer "+token)
	return nil
}

// HttpRequest injects Antigravity credentials into the request and executes it.
// It uses a whitelist approach: all incoming headers are stripped and only
// the minimum set required by the Antigravity protocol is explicitly set.
func (e *AntigravityExecutor) HttpRequest(ctx context.Context, auth *cliproxyauth.Auth, req *http.Request) (*http.Response, error) {
	if req == nil {
		return nil, fmt.Errorf("antigravity executor: request is nil")
	}
	if ctx == nil {
		ctx = req.Context()
	}
	httpReq := req.WithContext(ctx)

	// --- Whitelist: save only the headers we need from the original request ---
	contentType := httpReq.Header.Get("Content-Type")

	// Wipe ALL incoming headers
	for k := range httpReq.Header {
		delete(httpReq.Header, k)
	}

	// --- Set only the headers Antigravity actually sends ---
	if contentType != "" {
		httpReq.Header.Set("Content-Type", contentType)
	}
	// Content-Length is managed automatically by Go's http.Client from the Body
	httpReq.Header.Set("User-Agent", resolveUserAgent(auth))
	httpReq.Close = true // sends Connection: close

	// Inject Authorization: Bearer <token>
	if err := e.PrepareRequest(httpReq, auth); err != nil {
		return nil, err
	}

	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)
	return httpClient.Do(httpReq)
}

func injectEnabledCreditTypes(payload []byte) []byte {
	if len(payload) == 0 {
		return nil
	}
	if !gjson.ValidBytes(payload) {
		return nil
	}
	updated, err := sjson.SetRawBytes(payload, "enabledCreditTypes", []byte(`["GOOGLE_ONE_AI"]`))
	if err != nil {
		return nil
	}
	return updated
}

func classifyAntigravity429(body []byte) antigravity429Category {
	switch decideAntigravity429(body).kind {
	case antigravity429DecisionInstantRetrySameAuth, antigravity429DecisionShortCooldownSwitchAuth:
		return antigravity429RateLimited
	case antigravity429DecisionFullQuotaExhausted:
		return antigravity429QuotaExhausted
	case antigravity429DecisionSoftRetry:
		return antigravity429SoftRateLimit
	default:
		return antigravity429Unknown
	}
}

func decideAntigravity429(body []byte) antigravity429Decision {
	decision := antigravity429Decision{kind: antigravity429DecisionSoftRetry}
	if len(body) == 0 {
		return decision
	}

	if retryAfter, parseErr := parseRetryDelay(body); parseErr == nil && retryAfter != nil {
		decision.retryAfter = retryAfter
	}

	status := strings.TrimSpace(gjson.GetBytes(body, "error.status").String())
	if !strings.EqualFold(status, "RESOURCE_EXHAUSTED") {
		return decision
	}

	details := gjson.GetBytes(body, "error.details")
	if details.Exists() && details.IsArray() {
		for _, detail := range details.Array() {
			if detail.Get("@type").String() != "type.googleapis.com/google.rpc.ErrorInfo" {
				continue
			}
			reason := strings.TrimSpace(detail.Get("reason").String())
			decision.reason = reason
			switch {
			case strings.EqualFold(reason, "QUOTA_EXHAUSTED"):
				decision.kind = antigravity429DecisionFullQuotaExhausted
				return decision
			case strings.EqualFold(reason, "RATE_LIMIT_EXCEEDED"):
				if decision.retryAfter == nil {
					decision.kind = antigravity429DecisionSoftRetry
					return decision
				}
				switch {
				case *decision.retryAfter < antigravityInstantRetryThreshold:
					decision.kind = antigravity429DecisionInstantRetrySameAuth
				case *decision.retryAfter < antigravityShortQuotaCooldownThreshold:
					decision.kind = antigravity429DecisionShortCooldownSwitchAuth
				default:
					decision.kind = antigravity429DecisionFullQuotaExhausted
				}
				return decision
			}
		}
	}

	lowerBody := strings.ToLower(string(body))
	for _, keyword := range antigravityQuotaExhaustedKeywords {
		if strings.Contains(lowerBody, keyword) {
			decision.kind = antigravity429DecisionFullQuotaExhausted
			decision.reason = "quota_exhausted"
			return decision
		}
	}

	decision.kind = antigravity429DecisionSoftRetry
	return decision
}

func antigravityCreditsRetryEnabled(cfg *config.Config) bool {
	return cfg != nil && cfg.QuotaExceeded.AntigravityCredits
}

func clearAntigravityCreditsFailureState(auth *cliproxyauth.Auth) {
	if auth == nil || strings.TrimSpace(auth.ID) == "" {
		return
	}
	antigravityCreditsFailureByAuth.Delete(strings.TrimSpace(auth.ID))
}
func markAntigravityCreditsPermanentlyDisabled(auth *cliproxyauth.Auth) {
	if auth == nil || strings.TrimSpace(auth.ID) == "" {
		return
	}
	authID := strings.TrimSpace(auth.ID)
	state := antigravityCreditsFailureState{
		PermanentlyDisabled:      true,
		ExplicitBalanceExhausted: true,
	}
	antigravityCreditsFailureByAuth.Store(authID, state)
	antigravityCreditsBalanceByAuth.Store(authID, antigravityCreditsBalance{
		CreditAmount:    0,
		MinCreditAmount: 1,
		Known:           true,
	})
	cliproxyauth.SetAntigravityCreditsHint(authID, cliproxyauth.AntigravityCreditsHint{
		Known:           true,
		Available:       false,
		CreditAmount:    0,
		MinCreditAmount: 1,
		UpdatedAt:       time.Now(),
	})
}

func clearAntigravityCreditsPermanentlyDisabled(auth *cliproxyauth.Auth) {
	if auth == nil || strings.TrimSpace(auth.ID) == "" {
		return
	}
	antigravityCreditsFailureByAuth.Delete(strings.TrimSpace(auth.ID))
}

func antigravityHasExplicitCreditsBalanceExhaustedReason(body []byte) bool {
	if len(body) == 0 {
		return false
	}
	details := gjson.GetBytes(body, "error.details")
	if !details.Exists() || !details.IsArray() {
		return false
	}
	for _, detail := range details.Array() {
		if detail.Get("@type").String() != "type.googleapis.com/google.rpc.ErrorInfo" {
			continue
		}
		reason := strings.TrimSpace(detail.Get("reason").String())
		if strings.EqualFold(reason, "INSUFFICIENT_G1_CREDITS_BALANCE") {
			return true
		}
	}
	return false
}

func newAntigravityStatusErr(statusCode int, body []byte) statusErr {
	err := statusErr{code: statusCode, msg: string(body)}
	if statusCode == http.StatusTooManyRequests {
		if retryAfter, parseErr := parseRetryDelay(body); parseErr == nil && retryAfter != nil {
			err.retryAfter = retryAfter
		}
	}
	return err
}

// Execute performs a non-streaming request to the Antigravity API.
func (e *AntigravityExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, req cliproxyexecutor.Request, opts cliproxyexecutor.Options) (resp cliproxyexecutor.Response, err error) {
	if opts.Alt == "responses/compact" {
		return resp, statusErr{code: http.StatusNotImplemented, msg: "/responses/compact not supported"}
	}
	baseModel := thinking.ParseSuffix(req.Model).ModelName
	if inCooldown, remaining := antigravityIsInShortCooldown(auth, baseModel, time.Now()); inCooldown {
		log.Debugf("antigravity executor: auth %s in short cooldown for model %s (%s remaining), returning 429 to switch auth", auth.ID, baseModel, remaining)
		d := remaining
		return resp, statusErr{code: http.StatusTooManyRequests, msg: fmt.Sprintf("auth in short cooldown, %s remaining", remaining), retryAfter: &d}
	}

	isClaude := strings.Contains(strings.ToLower(baseModel), "claude")
	if isClaude || strings.Contains(baseModel, "gemini-3-pro") || strings.Contains(baseModel, "gemini-3.1-flash-image") {
		return e.executeClaudeNonStream(ctx, auth, req, opts)
	}

	reporter := helps.NewUsageReporter(ctx, e.Identifier(), baseModel, auth)
	defer reporter.TrackFailure(ctx, &err)

	from := opts.SourceFormat
	to := sdktranslator.FromString("antigravity")

	originalPayloadSource := req.Payload
	if len(opts.OriginalRequest) > 0 {
		originalPayloadSource = opts.OriginalRequest
	}
	originalPayload := originalPayloadSource
	originalPayload, errValidate := validateAntigravityRequestSignatures(from, originalPayload)
	if errValidate != nil {
		return resp, errValidate
	}
	req.Payload = originalPayload
	token, updatedAuth, errToken := e.ensureAccessToken(ctx, auth)
	if errToken != nil {
		return resp, errToken
	}
	if updatedAuth != nil {
		auth = updatedAuth
	}
	originalTranslated := sdktranslator.TranslateRequest(from, to, baseModel, originalPayload, false)
	translated := sdktranslator.TranslateRequest(from, to, baseModel, req.Payload, false)

	translated, err = thinking.ApplyThinking(translated, req.Model, from.String(), to.String(), e.Identifier())
	if err != nil {
		return resp, err
	}

	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel)

	useCredits := cliproxyauth.AntigravityCreditsRequested(ctx) && antigravityCreditsRetryEnabled(e.cfg)

	baseURLs := antigravityBaseURLFallbackOrder(auth)
	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)
	attempts := antigravityRetryAttempts(auth, e.cfg)

attemptLoop:
	for attempt := 0; attempt < attempts; attempt++ {
		var lastStatus int
		var lastBody []byte
		var lastErr error

		for idx, baseURL := range baseURLs {
			requestPayload := translated
			if useCredits {
				if cp := injectEnabledCreditTypes(translated); len(cp) > 0 {
					requestPayload = cp
					helps.MarkCreditsUsed(ctx)
				}
			}

			httpReq, errReq := e.buildRequest(ctx, auth, token, baseModel, requestPayload, false, opts.Alt, baseURL)
			if errReq != nil {
				err = errReq
				return resp, err
			}

			httpResp, errDo := httpClient.Do(httpReq)
			if errDo != nil {
				helps.RecordAPIResponseError(ctx, e.cfg, errDo)
				if errors.Is(errDo, context.Canceled) || errors.Is(errDo, context.DeadlineExceeded) {
					return resp, errDo
				}
				lastStatus = 0
				lastBody = nil
				lastErr = errDo
				if idx+1 < len(baseURLs) {
					log.Debugf("antigravity executor: request error on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
					continue
				}
				err = errDo
				return resp, err
			}

			helps.RecordAPIResponseMetadata(ctx, e.cfg, httpResp.StatusCode, httpResp.Header.Clone())
			bodyBytes, errRead := io.ReadAll(httpResp.Body)
			if errClose := httpResp.Body.Close(); errClose != nil {
				log.Errorf("antigravity executor: close response body error: %v", errClose)
			}
			if errRead != nil {
				helps.RecordAPIResponseError(ctx, e.cfg, errRead)
				err = errRead
				return resp, err
			}
			helps.AppendAPIResponseChunk(ctx, e.cfg, bodyBytes)

			if httpResp.StatusCode == http.StatusTooManyRequests {
				decision := decideAntigravity429(bodyBytes)
				switch decision.kind {
				case antigravity429DecisionInstantRetrySameAuth:
					if attempt+1 < attempts {
						if decision.retryAfter != nil && *decision.retryAfter > 0 {
							wait := antigravityInstantRetryDelay(*decision.retryAfter)
							log.Debugf("antigravity executor: instant retry for model %s, waiting %s", baseModel, wait)
							if errWait := antigravityWait(ctx, wait); errWait != nil {
								return resp, errWait
							}
						}
						continue attemptLoop
					}
				case antigravity429DecisionShortCooldownSwitchAuth:
					if decision.retryAfter != nil && *decision.retryAfter > 0 {
						markAntigravityShortCooldown(auth, baseModel, time.Now(), *decision.retryAfter)
						log.Debugf("antigravity executor: short quota cooldown (%s) for model %s, recorded cooldown", *decision.retryAfter, baseModel)
					}
				case antigravity429DecisionFullQuotaExhausted:
					if useCredits && antigravityHasExplicitCreditsBalanceExhaustedReason(bodyBytes) {
						markAntigravityCreditsPermanentlyDisabled(auth)
					}
					// No credits logic - just fall through to error return below
				}
			}

			if httpResp.StatusCode < http.StatusOK || httpResp.StatusCode >= http.StatusMultipleChoices {
				log.Debugf("antigravity executor: upstream error status: %d, body: %s", httpResp.StatusCode, helps.SummarizeErrorBody(httpResp.Header.Get("Content-Type"), bodyBytes))
				lastStatus = httpResp.StatusCode
				lastBody = append([]byte(nil), bodyBytes...)
				lastErr = nil
				if httpResp.StatusCode == http.StatusTooManyRequests && idx+1 < len(baseURLs) {
					log.Debugf("antigravity executor: rate limited on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
					continue
				}
				if antigravityShouldRetryTransientResourceExhausted429(httpResp.StatusCode, bodyBytes) && attempt+1 < attempts {
					delay := antigravityTransient429RetryDelay(attempt)
					log.Debugf("antigravity executor: transient 429 resource exhausted for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
					if errWait := antigravityWait(ctx, delay); errWait != nil {
						return resp, errWait
					}
					continue attemptLoop
				}
				if antigravityShouldRetryNoCapacity(httpResp.StatusCode, bodyBytes) {
					if idx+1 < len(baseURLs) {
						log.Debugf("antigravity executor: no capacity on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
						continue
					}
					if attempt+1 < attempts {
						delay := antigravityNoCapacityRetryDelay(attempt)
						log.Debugf("antigravity executor: no capacity for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
						if errWait := antigravityWait(ctx, delay); errWait != nil {
							return resp, errWait
						}
						continue attemptLoop
					}
				}
				if antigravityShouldRetrySoftRateLimit(httpResp.StatusCode, bodyBytes) {
					if attempt+1 < attempts {
						delay := antigravitySoftRateLimitDelay(attempt)
						log.Debugf("antigravity executor: soft rate limit for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
						if errWait := antigravityWait(ctx, delay); errWait != nil {
							return resp, errWait
						}
						continue attemptLoop
					}
				}
				err = newAntigravityStatusErr(httpResp.StatusCode, bodyBytes)
				return resp, err
			}

			// Success
			if useCredits {
				clearAntigravityCreditsFailureState(auth)
			}
			reporter.Publish(ctx, helps.ParseAntigravityUsage(bodyBytes))
			var param any
			converted := sdktranslator.TranslateNonStream(ctx, to, from, req.Model, opts.OriginalRequest, translated, bodyBytes, &param)
			resp = cliproxyexecutor.Response{Payload: converted, Headers: httpResp.Header.Clone()}
			reporter.EnsurePublished(ctx)
			return resp, nil
		}

		switch {
		case lastStatus != 0:
			err = newAntigravityStatusErr(lastStatus, lastBody)
		case lastErr != nil:
			err = lastErr
		default:
			err = statusErr{code: http.StatusServiceUnavailable, msg: "antigravity executor: no base url available"}
		}
		return resp, err
	}

	return resp, err
}

// executeClaudeNonStream performs a claude non-streaming request to the Antigravity API.
func (e *AntigravityExecutor) executeClaudeNonStream(ctx context.Context, auth *cliproxyauth.Auth, req cliproxyexecutor.Request, opts cliproxyexecutor.Options) (resp cliproxyexecutor.Response, err error) {
	baseModel := thinking.ParseSuffix(req.Model).ModelName
	if inCooldown, remaining := antigravityIsInShortCooldown(auth, baseModel, time.Now()); inCooldown {
		log.Debugf("antigravity executor: auth %s in short cooldown for model %s (%s remaining), returning 429 to switch auth", auth.ID, baseModel, remaining)
		d := remaining
		return resp, statusErr{code: http.StatusTooManyRequests, msg: fmt.Sprintf("auth in short cooldown, %s remaining", remaining), retryAfter: &d}
	}

	reporter := helps.NewUsageReporter(ctx, e.Identifier(), baseModel, auth)
	defer reporter.TrackFailure(ctx, &err)

	from := opts.SourceFormat
	to := sdktranslator.FromString("antigravity")

	originalPayloadSource := req.Payload
	if len(opts.OriginalRequest) > 0 {
		originalPayloadSource = opts.OriginalRequest
	}
	originalPayload := originalPayloadSource
	originalPayload, errValidate := validateAntigravityRequestSignatures(from, originalPayload)
	if errValidate != nil {
		return resp, errValidate
	}
	req.Payload = originalPayload
	token, updatedAuth, errToken := e.ensureAccessToken(ctx, auth)
	if errToken != nil {
		return resp, errToken
	}
	if updatedAuth != nil {
		auth = updatedAuth
	}
	originalTranslated := sdktranslator.TranslateRequest(from, to, baseModel, originalPayload, true)
	translated := sdktranslator.TranslateRequest(from, to, baseModel, req.Payload, true)

	translated, err = thinking.ApplyThinking(translated, req.Model, from.String(), to.String(), e.Identifier())
	if err != nil {
		return resp, err
	}

	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel)

	useCredits := cliproxyauth.AntigravityCreditsRequested(ctx) && antigravityCreditsRetryEnabled(e.cfg)

	baseURLs := antigravityBaseURLFallbackOrder(auth)
	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)

	attempts := antigravityRetryAttempts(auth, e.cfg)

attemptLoop:
	for attempt := 0; attempt < attempts; attempt++ {
		var lastStatus int
		var lastBody []byte
		var lastErr error

		for idx, baseURL := range baseURLs {
			requestPayload := translated
			if useCredits {
				if cp := injectEnabledCreditTypes(translated); len(cp) > 0 {
					requestPayload = cp
					helps.MarkCreditsUsed(ctx)
				}
			}
			httpReq, errReq := e.buildRequest(ctx, auth, token, baseModel, requestPayload, true, opts.Alt, baseURL)
			if errReq != nil {
				err = errReq
				return resp, err
			}

			httpResp, errDo := httpClient.Do(httpReq)
			if errDo != nil {
				helps.RecordAPIResponseError(ctx, e.cfg, errDo)
				if errors.Is(errDo, context.Canceled) || errors.Is(errDo, context.DeadlineExceeded) {
					return resp, errDo
				}
				lastStatus = 0
				lastBody = nil
				lastErr = errDo
				if idx+1 < len(baseURLs) {
					log.Debugf("antigravity executor: request error on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
					continue
				}
				err = errDo
				return resp, err
			}
			helps.RecordAPIResponseMetadata(ctx, e.cfg, httpResp.StatusCode, httpResp.Header.Clone())
			if httpResp.StatusCode < http.StatusOK || httpResp.StatusCode >= http.StatusMultipleChoices {
				bodyBytes, errRead := io.ReadAll(httpResp.Body)
				if errClose := httpResp.Body.Close(); errClose != nil {
					log.Errorf("antigravity executor: close response body error: %v", errClose)
				}
				if errRead != nil {
					helps.RecordAPIResponseError(ctx, e.cfg, errRead)
					if errors.Is(errRead, context.Canceled) || errors.Is(errRead, context.DeadlineExceeded) {
						err = errRead
						return resp, err
					}
					if errCtx := ctx.Err(); errCtx != nil {
						err = errCtx
						return resp, err
					}
					lastStatus = 0
					lastBody = nil
					lastErr = errRead
					if idx+1 < len(baseURLs) {
						log.Debugf("antigravity executor: read error on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
						continue
					}
					err = errRead
					return resp, err
				}
				helps.AppendAPIResponseChunk(ctx, e.cfg, bodyBytes)
				if httpResp.StatusCode == http.StatusTooManyRequests {
					decision := decideAntigravity429(bodyBytes)

					switch decision.kind {
					case antigravity429DecisionInstantRetrySameAuth:
						if attempt+1 < attempts {
							if decision.retryAfter != nil && *decision.retryAfter > 0 {
								wait := antigravityInstantRetryDelay(*decision.retryAfter)
								log.Debugf("antigravity executor: instant retry for model %s, waiting %s", baseModel, wait)
								if errWait := antigravityWait(ctx, wait); errWait != nil {
									return resp, errWait
								}
							}
							continue attemptLoop
						}
					case antigravity429DecisionShortCooldownSwitchAuth:
						if decision.retryAfter != nil && *decision.retryAfter > 0 {
							markAntigravityShortCooldown(auth, baseModel, time.Now(), *decision.retryAfter)
							log.Debugf("antigravity executor: short quota cooldown (%s) for model %s, recorded cooldown", *decision.retryAfter, baseModel)
						}
					case antigravity429DecisionFullQuotaExhausted:
						if useCredits && antigravityHasExplicitCreditsBalanceExhaustedReason(bodyBytes) {
							markAntigravityCreditsPermanentlyDisabled(auth)
						}
						// No credits logic - just fall through to error return below
					}
				}

				lastStatus = httpResp.StatusCode
				lastBody = append([]byte(nil), bodyBytes...)
				lastErr = nil
				if httpResp.StatusCode == http.StatusTooManyRequests && idx+1 < len(baseURLs) {
					log.Debugf("antigravity executor: rate limited on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
					continue
				}
				if antigravityShouldRetryTransientResourceExhausted429(httpResp.StatusCode, bodyBytes) && attempt+1 < attempts {
					delay := antigravityTransient429RetryDelay(attempt)
					log.Debugf("antigravity executor: transient 429 resource exhausted for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
					if errWait := antigravityWait(ctx, delay); errWait != nil {
						return resp, errWait
					}
					continue attemptLoop
				}
				if antigravityShouldRetryNoCapacity(httpResp.StatusCode, bodyBytes) {
					if idx+1 < len(baseURLs) {
						log.Debugf("antigravity executor: no capacity on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
						continue
					}
					if attempt+1 < attempts {
						delay := antigravityNoCapacityRetryDelay(attempt)
						log.Debugf("antigravity executor: no capacity for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
						if errWait := antigravityWait(ctx, delay); errWait != nil {
							return resp, errWait
						}
						continue attemptLoop
					}
				}
				if antigravityShouldRetrySoftRateLimit(httpResp.StatusCode, bodyBytes) {
					if attempt+1 < attempts {
						delay := antigravitySoftRateLimitDelay(attempt)
						log.Debugf("antigravity executor: soft rate limit for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
						if errWait := antigravityWait(ctx, delay); errWait != nil {
							return resp, errWait
						}
						continue attemptLoop
					}
				}
				err = newAntigravityStatusErr(httpResp.StatusCode, bodyBytes)
				return resp, err
			}

			// Stream success
			if useCredits {
				clearAntigravityCreditsFailureState(auth)
			}
			out := make(chan cliproxyexecutor.StreamChunk)
			go func(resp *http.Response) {
				defer close(out)
				defer func() {
					if errClose := resp.Body.Close(); errClose != nil {
						log.Errorf("antigravity executor: close response body error: %v", errClose)
					}
				}()
				scanner := bufio.NewScanner(resp.Body)
				scanner.Buffer(nil, streamScannerBuffer)
				for scanner.Scan() {
					line := scanner.Bytes()
					helps.AppendAPIResponseChunk(ctx, e.cfg, line)

					// Filter usage metadata for all models
					// Only retain usage statistics in the terminal chunk
					line = helps.FilterSSEUsageMetadata(line)

					payload := helps.JSONPayload(line)
					if payload == nil {
						continue
					}

					if detail, ok := helps.ParseAntigravityStreamUsage(payload); ok {
						reporter.Publish(ctx, detail)
					}

					out <- cliproxyexecutor.StreamChunk{Payload: payload}
				}
				if errScan := scanner.Err(); errScan != nil {
					helps.RecordAPIResponseError(ctx, e.cfg, errScan)
					reporter.PublishFailure(ctx)
					out <- cliproxyexecutor.StreamChunk{Err: errScan}
				} else {
					reporter.EnsurePublished(ctx)
				}
			}(httpResp)

			var buffer bytes.Buffer
			for chunk := range out {
				if chunk.Err != nil {
					return resp, chunk.Err
				}
				if len(chunk.Payload) > 0 {
					_, _ = buffer.Write(chunk.Payload)
					_, _ = buffer.Write([]byte("\n"))
				}
			}
			resp = cliproxyexecutor.Response{Payload: e.convertStreamToNonStream(buffer.Bytes())}

			reporter.Publish(ctx, helps.ParseAntigravityUsage(resp.Payload))
			var param any
			converted := sdktranslator.TranslateNonStream(ctx, to, from, req.Model, opts.OriginalRequest, translated, resp.Payload, &param)
			resp = cliproxyexecutor.Response{Payload: converted, Headers: httpResp.Header.Clone()}
			reporter.EnsurePublished(ctx)

			return resp, nil
		}

		switch {
		case lastStatus != 0:
			err = newAntigravityStatusErr(lastStatus, lastBody)
		case lastErr != nil:
			err = lastErr
		default:
			err = statusErr{code: http.StatusServiceUnavailable, msg: "antigravity executor: no base url available"}
		}
		return resp, err
	}

	return resp, err
}

func (e *AntigravityExecutor) convertStreamToNonStream(stream []byte) []byte {
	responseTemplate := ""
	var traceID string
	var finishReason string
	var modelVersion string
	var responseID string
	var role string
	var usageRaw string
	parts := make([]map[string]interface{}, 0)
	var pendingKind string
	var pendingText strings.Builder
	var pendingThoughtSig string

	flushPending := func() {
		if pendingKind == "" {
			return
		}
		text := pendingText.String()
		switch pendingKind {
		case "text":
			if strings.TrimSpace(text) == "" {
				pendingKind = ""
				pendingText.Reset()
				pendingThoughtSig = ""
				return
			}
			parts = append(parts, map[string]interface{}{"text": text})
		case "thought":
			if strings.TrimSpace(text) == "" && pendingThoughtSig == "" {
				pendingKind = ""
				pendingText.Reset()
				pendingThoughtSig = ""
				return
			}
			part := map[string]interface{}{"thought": true}
			part["text"] = text
			if pendingThoughtSig != "" {
				part["thoughtSignature"] = pendingThoughtSig
			}
			parts = append(parts, part)
		}
		pendingKind = ""
		pendingText.Reset()
		pendingThoughtSig = ""
	}

	normalizePart := func(partResult gjson.Result) map[string]interface{} {
		var m map[string]interface{}
		_ = json.Unmarshal([]byte(partResult.Raw), &m)
		if m == nil {
			m = map[string]interface{}{}
		}
		sig := partResult.Get("thoughtSignature").String()
		if sig == "" {
			sig = partResult.Get("thought_signature").String()
		}
		if sig != "" {
			m["thoughtSignature"] = sig
			delete(m, "thought_signature")
		}
		if inlineData, ok := m["inline_data"]; ok {
			m["inlineData"] = inlineData
			delete(m, "inline_data")
		}
		return m
	}

	for _, line := range bytes.Split(stream, []byte("\n")) {
		trimmed := bytes.TrimSpace(line)
		if len(trimmed) == 0 || !gjson.ValidBytes(trimmed) {
			continue
		}

		root := gjson.ParseBytes(trimmed)
		responseNode := root.Get("response")
		if !responseNode.Exists() {
			if root.Get("candidates").Exists() {
				responseNode = root
			} else {
				continue
			}
		}
		responseTemplate = responseNode.Raw

		if traceResult := root.Get("traceId"); traceResult.Exists() && traceResult.String() != "" {
			traceID = traceResult.String()
		}

		if roleResult := responseNode.Get("candidates.0.content.role"); roleResult.Exists() {
			role = roleResult.String()
		}

		if finishResult := responseNode.Get("candidates.0.finishReason"); finishResult.Exists() && finishResult.String() != "" {
			finishReason = finishResult.String()
		}

		if modelResult := responseNode.Get("modelVersion"); modelResult.Exists() && modelResult.String() != "" {
			modelVersion = modelResult.String()
		}
		if responseIDResult := responseNode.Get("responseId"); responseIDResult.Exists() && responseIDResult.String() != "" {
			responseID = responseIDResult.String()
		}
		if usageResult := responseNode.Get("usageMetadata"); usageResult.Exists() {
			usageRaw = usageResult.Raw
		} else if usageMetadataResult := root.Get("usageMetadata"); usageMetadataResult.Exists() {
			usageRaw = usageMetadataResult.Raw
		}

		if partsResult := responseNode.Get("candidates.0.content.parts"); partsResult.IsArray() {
			for _, part := range partsResult.Array() {
				hasFunctionCall := part.Get("functionCall").Exists()
				hasInlineData := part.Get("inlineData").Exists() || part.Get("inline_data").Exists()
				sig := part.Get("thoughtSignature").String()
				if sig == "" {
					sig = part.Get("thought_signature").String()
				}
				text := part.Get("text").String()
				thought := part.Get("thought").Bool()

				if hasFunctionCall || hasInlineData {
					flushPending()
					parts = append(parts, normalizePart(part))
					continue
				}

				if thought || part.Get("text").Exists() {
					kind := "text"
					if thought {
						kind = "thought"
					}
					if pendingKind != "" && pendingKind != kind {
						flushPending()
					}
					pendingKind = kind
					pendingText.WriteString(text)
					if kind == "thought" && sig != "" {
						pendingThoughtSig = sig
					}
					continue
				}

				flushPending()
				parts = append(parts, normalizePart(part))
			}
		}
	}
	flushPending()

	if responseTemplate == "" {
		responseTemplate = `{"candidates":[{"content":{"role":"model","parts":[]}}]}`
	}

	partsJSON, _ := json.Marshal(parts)
	updatedTemplate, _ := sjson.SetRawBytes([]byte(responseTemplate), "candidates.0.content.parts", partsJSON)
	responseTemplate = string(updatedTemplate)
	if role != "" {
		updatedTemplate, _ = sjson.SetBytes([]byte(responseTemplate), "candidates.0.content.role", role)
		responseTemplate = string(updatedTemplate)
	}
	if finishReason != "" {
		updatedTemplate, _ = sjson.SetBytes([]byte(responseTemplate), "candidates.0.finishReason", finishReason)
		responseTemplate = string(updatedTemplate)
	}
	if modelVersion != "" {
		updatedTemplate, _ = sjson.SetBytes([]byte(responseTemplate), "modelVersion", modelVersion)
		responseTemplate = string(updatedTemplate)
	}
	if responseID != "" {
		updatedTemplate, _ = sjson.SetBytes([]byte(responseTemplate), "responseId", responseID)
		responseTemplate = string(updatedTemplate)
	}
	if usageRaw != "" {
		updatedTemplate, _ = sjson.SetRawBytes([]byte(responseTemplate), "usageMetadata", []byte(usageRaw))
		responseTemplate = string(updatedTemplate)
	} else if !gjson.Get(responseTemplate, "usageMetadata").Exists() {
		updatedTemplate, _ = sjson.SetBytes([]byte(responseTemplate), "usageMetadata.promptTokenCount", 0)
		responseTemplate = string(updatedTemplate)
		updatedTemplate, _ = sjson.SetBytes([]byte(responseTemplate), "usageMetadata.candidatesTokenCount", 0)
		responseTemplate = string(updatedTemplate)
		updatedTemplate, _ = sjson.SetBytes([]byte(responseTemplate), "usageMetadata.totalTokenCount", 0)
		responseTemplate = string(updatedTemplate)
	}

	output := `{"response":{},"traceId":""}`
	updatedOutput, _ := sjson.SetRawBytes([]byte(output), "response", []byte(responseTemplate))
	output = string(updatedOutput)
	if traceID != "" {
		updatedOutput, _ = sjson.SetBytes([]byte(output), "traceId", traceID)
		output = string(updatedOutput)
	}
	return []byte(output)
}

// ExecuteStream performs a streaming request to the Antigravity API.
func (e *AntigravityExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.Auth, req cliproxyexecutor.Request, opts cliproxyexecutor.Options) (_ *cliproxyexecutor.StreamResult, err error) {
	if opts.Alt == "responses/compact" {
		return nil, statusErr{code: http.StatusNotImplemented, msg: "/responses/compact not supported"}
	}
	baseModel := thinking.ParseSuffix(req.Model).ModelName

	ctx = context.WithValue(ctx, "alt", "")
	if inCooldown, remaining := antigravityIsInShortCooldown(auth, baseModel, time.Now()); inCooldown {
		log.Debugf("antigravity executor: auth %s in short cooldown for model %s (%s remaining), returning 429 to switch auth", auth.ID, baseModel, remaining)
		d := remaining
		return nil, statusErr{code: http.StatusTooManyRequests, msg: fmt.Sprintf("auth in short cooldown, %s remaining", remaining), retryAfter: &d}
	}

	reporter := helps.NewUsageReporter(ctx, e.Identifier(), baseModel, auth)
	defer reporter.TrackFailure(ctx, &err)

	from := opts.SourceFormat
	to := sdktranslator.FromString("antigravity")

	originalPayloadSource := req.Payload
	if len(opts.OriginalRequest) > 0 {
		originalPayloadSource = opts.OriginalRequest
	}
	originalPayload := originalPayloadSource
	originalPayload, errValidate := validateAntigravityRequestSignatures(from, originalPayload)
	if errValidate != nil {
		return nil, errValidate
	}
	req.Payload = originalPayload
	token, updatedAuth, errToken := e.ensureAccessToken(ctx, auth)
	if errToken != nil {
		return nil, errToken
	}
	if updatedAuth != nil {
		auth = updatedAuth
	}

	originalTranslated := sdktranslator.TranslateRequest(from, to, baseModel, originalPayload, true)
	translated := sdktranslator.TranslateRequest(from, to, baseModel, req.Payload, true)

	translated, err = thinking.ApplyThinking(translated, req.Model, from.String(), to.String(), e.Identifier())
	if err != nil {
		return nil, err
	}

	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel)

	useCredits := cliproxyauth.AntigravityCreditsRequested(ctx) && antigravityCreditsRetryEnabled(e.cfg)

	baseURLs := antigravityBaseURLFallbackOrder(auth)
	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)

	attempts := antigravityRetryAttempts(auth, e.cfg)

attemptLoop:
	for attempt := 0; attempt < attempts; attempt++ {
		var lastStatus int
		var lastBody []byte
		var lastErr error

		for idx, baseURL := range baseURLs {
			requestPayload := translated
			if useCredits {
				if cp := injectEnabledCreditTypes(translated); len(cp) > 0 {
					requestPayload = cp
					helps.MarkCreditsUsed(ctx)
				}
			}
			httpReq, errReq := e.buildRequest(ctx, auth, token, baseModel, requestPayload, true, opts.Alt, baseURL)
			if errReq != nil {
				err = errReq
				return nil, err
			}
			httpResp, errDo := httpClient.Do(httpReq)
			if errDo != nil {
				helps.RecordAPIResponseError(ctx, e.cfg, errDo)
				if errors.Is(errDo, context.Canceled) || errors.Is(errDo, context.DeadlineExceeded) {
					return nil, errDo
				}
				lastStatus = 0
				lastBody = nil
				lastErr = errDo
				if idx+1 < len(baseURLs) {
					log.Debugf("antigravity executor: request error on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
					continue
				}
				err = errDo
				return nil, err
			}
			helps.RecordAPIResponseMetadata(ctx, e.cfg, httpResp.StatusCode, httpResp.Header.Clone())
			if httpResp.StatusCode < http.StatusOK || httpResp.StatusCode >= http.StatusMultipleChoices {
				bodyBytes, errRead := io.ReadAll(httpResp.Body)
				if errClose := httpResp.Body.Close(); errClose != nil {
					log.Errorf("antigravity executor: close response body error: %v", errClose)
				}
				if errRead != nil {
					helps.RecordAPIResponseError(ctx, e.cfg, errRead)
					if errors.Is(errRead, context.Canceled) || errors.Is(errRead, context.DeadlineExceeded) {
						err = errRead
						return nil, err
					}
					if errCtx := ctx.Err(); errCtx != nil {
						err = errCtx
						return nil, err
					}
					lastStatus = 0
					lastBody = nil
					lastErr = errRead
					if idx+1 < len(baseURLs) {
						log.Debugf("antigravity executor: read error on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
						continue
					}
					err = errRead
					return nil, err
				}
				helps.AppendAPIResponseChunk(ctx, e.cfg, bodyBytes)
				if httpResp.StatusCode == http.StatusTooManyRequests {
					decision := decideAntigravity429(bodyBytes)

					switch decision.kind {
					case antigravity429DecisionInstantRetrySameAuth:
						if attempt+1 < attempts {
							if decision.retryAfter != nil && *decision.retryAfter > 0 {
								wait := antigravityInstantRetryDelay(*decision.retryAfter)
								log.Debugf("antigravity executor: instant retry for model %s, waiting %s", baseModel, wait)
								if errWait := antigravityWait(ctx, wait); errWait != nil {
									return nil, errWait
								}
							}
							continue attemptLoop
						}
					case antigravity429DecisionShortCooldownSwitchAuth:
						if decision.retryAfter != nil && *decision.retryAfter > 0 {
							markAntigravityShortCooldown(auth, baseModel, time.Now(), *decision.retryAfter)
							log.Debugf("antigravity executor: short quota cooldown (%s) for model %s recorded", *decision.retryAfter, baseModel)
						}
					case antigravity429DecisionFullQuotaExhausted:
						if useCredits && antigravityHasExplicitCreditsBalanceExhaustedReason(bodyBytes) {
							markAntigravityCreditsPermanentlyDisabled(auth)
						}
						// No credits logic - just fall through to error return below
					}
				}

				lastStatus = httpResp.StatusCode
				lastBody = append([]byte(nil), bodyBytes...)
				lastErr = nil
				if httpResp.StatusCode == http.StatusTooManyRequests && idx+1 < len(baseURLs) {
					log.Debugf("antigravity executor: rate limited on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
					continue
				}
				if antigravityShouldRetryTransientResourceExhausted429(httpResp.StatusCode, bodyBytes) && attempt+1 < attempts {
					delay := antigravityTransient429RetryDelay(attempt)
					log.Debugf("antigravity executor: transient 429 resource exhausted for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
					if errWait := antigravityWait(ctx, delay); errWait != nil {
						return nil, errWait
					}
					continue attemptLoop
				}
				if antigravityShouldRetryNoCapacity(httpResp.StatusCode, bodyBytes) {
					if idx+1 < len(baseURLs) {
						log.Debugf("antigravity executor: no capacity on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
						continue
					}
					if attempt+1 < attempts {
						delay := antigravityNoCapacityRetryDelay(attempt)
						log.Debugf("antigravity executor: no capacity for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
						if errWait := antigravityWait(ctx, delay); errWait != nil {
							return nil, errWait
						}
						continue attemptLoop
					}
				}
				if antigravityShouldRetrySoftRateLimit(httpResp.StatusCode, bodyBytes) {
					if attempt+1 < attempts {
						delay := antigravitySoftRateLimitDelay(attempt)
						log.Debugf("antigravity executor: soft rate limit for model %s, retrying in %s (attempt %d/%d)", baseModel, delay, attempt+1, attempts)
						if errWait := antigravityWait(ctx, delay); errWait != nil {
							return nil, errWait
						}
						continue attemptLoop
					}
				}
				err = newAntigravityStatusErr(httpResp.StatusCode, bodyBytes)
				return nil, err
			}

			// Stream success
			if useCredits {
				clearAntigravityCreditsFailureState(auth)
			}
			out := make(chan cliproxyexecutor.StreamChunk)
			go func(resp *http.Response) {
				defer close(out)
				defer func() {
					if errClose := resp.Body.Close(); errClose != nil {
						log.Errorf("antigravity executor: close response body error: %v", errClose)
					}
				}()
				scanner := bufio.NewScanner(resp.Body)
				scanner.Buffer(nil, streamScannerBuffer)
				var param any
				for scanner.Scan() {
					line := scanner.Bytes()
					helps.AppendAPIResponseChunk(ctx, e.cfg, line)

					// Filter usage metadata for all models
					// Only retain usage statistics in the terminal chunk
					line = helps.FilterSSEUsageMetadata(line)

					payload := helps.JSONPayload(line)
					if payload == nil {
						continue
					}

					if detail, ok := helps.ParseAntigravityStreamUsage(payload); ok {
						reporter.Publish(ctx, detail)
					}

					chunks := sdktranslator.TranslateStream(ctx, to, from, req.Model, opts.OriginalRequest, translated, bytes.Clone(payload), &param)
					for i := range chunks {
						out <- cliproxyexecutor.StreamChunk{Payload: chunks[i]}
					}
				}
				tail := sdktranslator.TranslateStream(ctx, to, from, req.Model, opts.OriginalRequest, translated, []byte("[DONE]"), &param)
				for i := range tail {
					out <- cliproxyexecutor.StreamChunk{Payload: tail[i]}
				}
				if errScan := scanner.Err(); errScan != nil {
					helps.RecordAPIResponseError(ctx, e.cfg, errScan)
					reporter.PublishFailure(ctx)
					out <- cliproxyexecutor.StreamChunk{Err: errScan}
				} else {
					reporter.EnsurePublished(ctx)
				}
			}(httpResp)
			return &cliproxyexecutor.StreamResult{Headers: httpResp.Header.Clone(), Chunks: out}, nil
		}

		switch {
		case lastStatus != 0:
			err = newAntigravityStatusErr(lastStatus, lastBody)
		case lastErr != nil:
			err = lastErr
		default:
			err = statusErr{code: http.StatusServiceUnavailable, msg: "antigravity executor: no base url available"}
		}
		return nil, err
	}

	return nil, err
}

// Refresh refreshes the authentication credentials using the refresh token.
func (e *AntigravityExecutor) Refresh(ctx context.Context, auth *cliproxyauth.Auth) (*cliproxyauth.Auth, error) {
	if auth == nil {
		return auth, nil
	}
	updated, errRefresh := e.refreshToken(ctx, auth.Clone())
	if errRefresh != nil {
		return nil, errRefresh
	}
	return updated, nil
}

// CountTokens counts tokens for the given request using the Antigravity API.
func (e *AntigravityExecutor) CountTokens(ctx context.Context, auth *cliproxyauth.Auth, req cliproxyexecutor.Request, opts cliproxyexecutor.Options) (cliproxyexecutor.Response, error) {
	baseModel := thinking.ParseSuffix(req.Model).ModelName

	from := opts.SourceFormat
	to := sdktranslator.FromString("antigravity")
	respCtx := context.WithValue(ctx, "alt", opts.Alt)
	originalPayloadSource := req.Payload
	if len(opts.OriginalRequest) > 0 {
		originalPayloadSource = opts.OriginalRequest
	}
	originalPayloadSource, errValidate := validateAntigravityRequestSignatures(from, originalPayloadSource)
	if errValidate != nil {
		return cliproxyexecutor.Response{}, errValidate
	}
	req.Payload = originalPayloadSource
	token, updatedAuth, errToken := e.ensureAccessToken(ctx, auth)
	if errToken != nil {
		return cliproxyexecutor.Response{}, errToken
	}
	if updatedAuth != nil {
		auth = updatedAuth
	}
	if strings.TrimSpace(token) == "" {
		return cliproxyexecutor.Response{}, statusErr{code: http.StatusUnauthorized, msg: "missing access token"}
	}

	// Prepare payload once (doesn't depend on baseURL)
	payload := sdktranslator.TranslateRequest(from, to, baseModel, req.Payload, false)

	payload, err := thinking.ApplyThinking(payload, req.Model, from.String(), to.String(), e.Identifier())
	if err != nil {
		return cliproxyexecutor.Response{}, err
	}

	payload = deleteJSONField(payload, "project")
	payload = deleteJSONField(payload, "model")
	payload = deleteJSONField(payload, "request.safetySettings")

	baseURLs := antigravityBaseURLFallbackOrder(auth)
	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)

	var authID, authLabel, authType, authValue string
	if auth != nil {
		authID = auth.ID
		authLabel = auth.Label
		authType, authValue = auth.AccountInfo()
	}

	var lastStatus int
	var lastBody []byte
	var lastErr error

	for idx, baseURL := range baseURLs {
		base := strings.TrimSuffix(baseURL, "/")
		if base == "" {
			base = buildBaseURL(auth)
		}

		var requestURL strings.Builder
		requestURL.WriteString(base)
		requestURL.WriteString(antigravityCountTokensPath)
		if opts.Alt != "" {
			requestURL.WriteString("?$alt=")
			requestURL.WriteString(url.QueryEscape(opts.Alt))
		}

		httpReq, errReq := http.NewRequestWithContext(ctx, http.MethodPost, requestURL.String(), bytes.NewReader(payload))
		if errReq != nil {
			return cliproxyexecutor.Response{}, errReq
		}
		httpReq.Close = true
		httpReq.Header.Set("Content-Type", "application/json")
		httpReq.Header.Set("Authorization", "Bearer "+token)
		httpReq.Header.Set("User-Agent", resolveUserAgent(auth))
		if host := resolveHost(base); host != "" {
			httpReq.Host = host
		}
		var attrs map[string]string
		if auth != nil {
			attrs = auth.Attributes
		}
		util.ApplyCustomHeadersFromAttrs(httpReq, attrs)

		helps.RecordAPIRequest(ctx, e.cfg, helps.UpstreamRequestLog{
			URL:       requestURL.String(),
			Method:    http.MethodPost,
			Headers:   httpReq.Header.Clone(),
			Body:      payload,
			Provider:  e.Identifier(),
			AuthID:    authID,
			AuthLabel: authLabel,
			AuthType:  authType,
			AuthValue: authValue,
		})

		httpResp, errDo := httpClient.Do(httpReq)
		if errDo != nil {
			helps.RecordAPIResponseError(ctx, e.cfg, errDo)
			if errors.Is(errDo, context.Canceled) || errors.Is(errDo, context.DeadlineExceeded) {
				return cliproxyexecutor.Response{}, errDo
			}
			lastStatus = 0
			lastBody = nil
			lastErr = errDo
			if idx+1 < len(baseURLs) {
				log.Debugf("antigravity executor: request error on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
				continue
			}
			return cliproxyexecutor.Response{}, errDo
		}

		helps.RecordAPIResponseMetadata(ctx, e.cfg, httpResp.StatusCode, httpResp.Header.Clone())
		bodyBytes, errRead := io.ReadAll(httpResp.Body)
		if errClose := httpResp.Body.Close(); errClose != nil {
			log.Errorf("antigravity executor: close response body error: %v", errClose)
		}
		if errRead != nil {
			helps.RecordAPIResponseError(ctx, e.cfg, errRead)
			return cliproxyexecutor.Response{}, errRead
		}
		helps.AppendAPIResponseChunk(ctx, e.cfg, bodyBytes)

		if httpResp.StatusCode >= http.StatusOK && httpResp.StatusCode < http.StatusMultipleChoices {
			count := gjson.GetBytes(bodyBytes, "totalTokens").Int()
			translated := sdktranslator.TranslateTokenCount(respCtx, to, from, count, bodyBytes)
			return cliproxyexecutor.Response{Payload: translated, Headers: httpResp.Header.Clone()}, nil
		}

		lastStatus = httpResp.StatusCode
		lastBody = append([]byte(nil), bodyBytes...)
		lastErr = nil
		if httpResp.StatusCode == http.StatusTooManyRequests && idx+1 < len(baseURLs) {
			log.Debugf("antigravity executor: rate limited on base url %s, retrying with fallback base url: %s", baseURL, baseURLs[idx+1])
			continue
		}
		sErr := statusErr{code: httpResp.StatusCode, msg: string(bodyBytes)}
		if httpResp.StatusCode == http.StatusTooManyRequests {
			if retryAfter, parseErr := parseRetryDelay(bodyBytes); parseErr == nil && retryAfter != nil {
				sErr.retryAfter = retryAfter
			}
		}
		return cliproxyexecutor.Response{}, sErr
	}

	switch {
	case lastStatus != 0:
		sErr := statusErr{code: lastStatus, msg: string(lastBody)}
		if lastStatus == http.StatusTooManyRequests {
			if retryAfter, parseErr := parseRetryDelay(lastBody); parseErr == nil && retryAfter != nil {
				sErr.retryAfter = retryAfter
			}
		}
		return cliproxyexecutor.Response{}, sErr
	case lastErr != nil:
		return cliproxyexecutor.Response{}, lastErr
	default:
		return cliproxyexecutor.Response{}, statusErr{code: http.StatusServiceUnavailable, msg: "antigravity executor: no base url available"}
	}
}

func (e *AntigravityExecutor) ensureAccessToken(ctx context.Context, auth *cliproxyauth.Auth) (string, *cliproxyauth.Auth, error) {
	if auth == nil {
		return "", nil, statusErr{code: http.StatusUnauthorized, msg: "missing auth"}
	}
	accessToken := metaStringValue(auth.Metadata, "access_token")
	expiry := tokenExpiry(auth.Metadata)
	if accessToken != "" && expiry.After(time.Now().Add(refreshSkew)) {
		e.maybeRefreshAntigravityCreditsHint(ctx, auth, accessToken)
		return accessToken, nil, nil
	}
	refreshCtx := context.Background()
	if ctx != nil {
		if rt, ok := ctx.Value("cliproxy.roundtripper").(http.RoundTripper); ok && rt != nil {
			refreshCtx = context.WithValue(refreshCtx, "cliproxy.roundtripper", rt)
		}
	}
	updated, errRefresh := e.refreshToken(refreshCtx, auth.Clone())
	if errRefresh != nil {
		return "", nil, errRefresh
	}
	return metaStringValue(updated.Metadata, "access_token"), updated, nil
}

func (e *AntigravityExecutor) maybeRefreshAntigravityCreditsHint(ctx context.Context, auth *cliproxyauth.Auth, accessToken string) {
	if e == nil || auth == nil || !antigravityCreditsRetryEnabled(e.cfg) {
		return
	}
	if ctx != nil && ctx.Err() != nil {
		return
	}
	authID := strings.TrimSpace(auth.ID)
	if authID == "" {
		return
	}
	if hint, ok := cliproxyauth.GetAntigravityCreditsHint(authID); ok && hint.Known {
		return
	}
	if strings.TrimSpace(accessToken) == "" {
		accessToken = metaStringValue(auth.Metadata, "access_token")
	}
	if strings.TrimSpace(accessToken) == "" {
		return
	}

	state := &antigravityCreditsHintRefreshState{}
	if existing, loaded := antigravityCreditsHintRefreshByID.LoadOrStore(authID, state); loaded {
		if cast, ok := existing.(*antigravityCreditsHintRefreshState); ok && cast != nil {
			state = cast
		} else {
			antigravityCreditsHintRefreshByID.Delete(authID)
			antigravityCreditsHintRefreshByID.Store(authID, state)
		}
	}

	now := time.Now()
	if !state.mu.TryLock() {
		return
	}
	if !state.lastAttempt.IsZero() && now.Sub(state.lastAttempt) < antigravityCreditsHintRefreshInterval {
		state.mu.Unlock()
		return
	}
	state.lastAttempt = now

	refreshCtx := context.Background()
	if ctx != nil {
		if rt, ok := ctx.Value("cliproxy.roundtripper").(http.RoundTripper); ok && rt != nil {
			refreshCtx = context.WithValue(refreshCtx, "cliproxy.roundtripper", rt)
		}
	}
	refreshCtx, cancel := context.WithTimeout(refreshCtx, antigravityCreditsHintRefreshTimeout)
	authCopy := auth.Clone()

	go func(state *antigravityCreditsHintRefreshState, auth *cliproxyauth.Auth, token string) {
		defer cancel()
		defer state.mu.Unlock()
		e.updateAntigravityCreditsBalance(refreshCtx, auth, token)
	}(state, authCopy, accessToken)
}

func (e *AntigravityExecutor) refreshToken(ctx context.Context, auth *cliproxyauth.Auth) (*cliproxyauth.Auth, error) {
	if auth == nil {
		return nil, statusErr{code: http.StatusUnauthorized, msg: "missing auth"}
	}
	refreshToken := metaStringValue(auth.Metadata, "refresh_token")
	if refreshToken == "" {
		return auth, statusErr{code: http.StatusUnauthorized, msg: "missing refresh token"}
	}

	form := url.Values{}
	form.Set("client_id", antigravityClientID)
	form.Set("client_secret", antigravityClientSecret)
	form.Set("grant_type", "refresh_token")
	form.Set("refresh_token", refreshToken)

	httpReq, errReq := http.NewRequestWithContext(ctx, http.MethodPost, "https://oauth2.googleapis.com/token", strings.NewReader(form.Encode()))
	if errReq != nil {
		return auth, errReq
	}
	httpReq.Header.Set("Host", "oauth2.googleapis.com")
	httpReq.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	// Real Antigravity uses Go's default User-Agent for OAuth token refresh
	httpReq.Header.Set("User-Agent", "Go-http-client/2.0")

	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)
	httpResp, errDo := httpClient.Do(httpReq)
	if errDo != nil {
		return auth, errDo
	}
	defer func() {
		if errClose := httpResp.Body.Close(); errClose != nil {
			log.Errorf("antigravity executor: close response body error: %v", errClose)
		}
	}()

	bodyBytes, errRead := io.ReadAll(httpResp.Body)
	if errRead != nil {
		return auth, errRead
	}

	if httpResp.StatusCode < http.StatusOK || httpResp.StatusCode >= http.StatusMultipleChoices {
		sErr := statusErr{code: httpResp.StatusCode, msg: string(bodyBytes)}
		if httpResp.StatusCode == http.StatusTooManyRequests {
			if retryAfter, parseErr := parseRetryDelay(bodyBytes); parseErr == nil && retryAfter != nil {
				sErr.retryAfter = retryAfter
			}
		}
		return auth, sErr
	}

	var tokenResp struct {
		AccessToken  string `json:"access_token"`
		RefreshToken string `json:"refresh_token"`
		ExpiresIn    int64  `json:"expires_in"`
		TokenType    string `json:"token_type"`
	}
	if errUnmarshal := json.Unmarshal(bodyBytes, &tokenResp); errUnmarshal != nil {
		return auth, errUnmarshal
	}

	if auth.Metadata == nil {
		auth.Metadata = make(map[string]any)
	}
	auth.Metadata["access_token"] = tokenResp.AccessToken
	if tokenResp.RefreshToken != "" {
		auth.Metadata["refresh_token"] = tokenResp.RefreshToken
	}
	auth.Metadata["expires_in"] = tokenResp.ExpiresIn
	now := time.Now()
	auth.Metadata["timestamp"] = now.UnixMilli()
	auth.Metadata["expired"] = now.Add(time.Duration(tokenResp.ExpiresIn) * time.Second).Format(time.RFC3339)
	auth.Metadata["type"] = antigravityAuthType
	if errProject := e.ensureAntigravityProjectID(ctx, auth, tokenResp.AccessToken); errProject != nil {
		log.Warnf("antigravity executor: ensure project id failed: %v", errProject)
	}
	e.updateAntigravityCreditsBalance(ctx, auth, tokenResp.AccessToken)
	return auth, nil
}

func (e *AntigravityExecutor) ensureAntigravityProjectID(ctx context.Context, auth *cliproxyauth.Auth, accessToken string) error {
	if auth == nil {
		return nil
	}

	if auth.Metadata["project_id"] != nil {
		return nil
	}

	token := strings.TrimSpace(accessToken)
	if token == "" {
		token = metaStringValue(auth.Metadata, "access_token")
	}
	if token == "" {
		return nil
	}

	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)
	projectID, errFetch := sdkAuth.FetchAntigravityProjectID(ctx, token, httpClient)
	if errFetch != nil {
		return errFetch
	}
	if strings.TrimSpace(projectID) == "" {
		return nil
	}
	if auth.Metadata == nil {
		auth.Metadata = make(map[string]any)
	}
	auth.Metadata["project_id"] = strings.TrimSpace(projectID)

	return nil
}

func (e *AntigravityExecutor) updateAntigravityCreditsBalance(ctx context.Context, auth *cliproxyauth.Auth, accessToken string) {
	if auth == nil || strings.TrimSpace(auth.ID) == "" {
		return
	}
	token := strings.TrimSpace(accessToken)
	if token == "" {
		token = metaStringValue(auth.Metadata, "access_token")
	}
	if token == "" {
		return
	}

	loadReqBody := `{"metadata":{"ideType":"ANTIGRAVITY","platform":"PLATFORM_UNSPECIFIED","pluginType":"GEMINI"}}`
	endpointURL := "https://cloudcode-pa.googleapis.com/v1internal:loadCodeAssist"
	httpReq, errReq := http.NewRequestWithContext(ctx, http.MethodPost, endpointURL, strings.NewReader(loadReqBody))
	if errReq != nil {
		log.Debugf("antigravity executor: create loadCodeAssist request error: %v", errReq)
		return
	}
	httpReq.Header.Set("Authorization", "Bearer "+token)
	httpReq.Header.Set("Content-Type", "application/json")
	httpReq.Header.Set("User-Agent", "google-api-nodejs-client/9.15.1")

	httpClient := newAntigravityHTTPClient(ctx, e.cfg, auth, 0)
	httpResp, errDo := httpClient.Do(httpReq)
	if errDo != nil {
		log.Debugf("antigravity executor: loadCodeAssist request error: %v", errDo)
		return
	}
	defer func() {
		if errClose := httpResp.Body.Close(); errClose != nil {
			log.Errorf("antigravity executor: close loadCodeAssist response body error: %v", errClose)
		}
	}()

	bodyBytes, errRead := io.ReadAll(httpResp.Body)
	if errRead != nil || httpResp.StatusCode < http.StatusOK || httpResp.StatusCode >= http.StatusMultipleChoices {
		log.Debugf("antigravity executor: loadCodeAssist returned status %d, err=%v", httpResp.StatusCode, errRead)
		return
	}

	authID := strings.TrimSpace(auth.ID)
	paidTierID := strings.TrimSpace(gjson.GetBytes(bodyBytes, "paidTier.id").String())

	credits := gjson.GetBytes(bodyBytes, "paidTier.availableCredits")
	if !credits.IsArray() {
		cliproxyauth.SetAntigravityCreditsHint(authID, cliproxyauth.AntigravityCreditsHint{
			Known:      true,
			Available:  false,
			PaidTierID: paidTierID,
			UpdatedAt:  time.Now(),
		})
		return
	}
	for _, credit := range credits.Array() {
		if !strings.EqualFold(credit.Get("creditType").String(), "GOOGLE_ONE_AI") {
			continue
		}
		creditAmount, errCA := strconv.ParseFloat(strings.TrimSpace(credit.Get("creditAmount").String()), 64)
		if errCA != nil {
			continue
		}
		minAmount, errMA := strconv.ParseFloat(strings.TrimSpace(credit.Get("minimumCreditAmountForUsage").String()), 64)
		if errMA != nil {
			continue
		}
		bal := antigravityCreditsBalance{
			CreditAmount:    creditAmount,
			MinCreditAmount: minAmount,
			PaidTierID:      paidTierID,
			Known:           true,
		}
		antigravityCreditsBalanceByAuth.Store(authID, bal)
		cliproxyauth.SetAntigravityCreditsHint(authID, cliproxyauth.AntigravityCreditsHint{
			Known:           true,
			Available:       creditAmount >= minAmount,
			CreditAmount:    creditAmount,
			MinCreditAmount: minAmount,
			PaidTierID:      paidTierID,
			UpdatedAt:       time.Now(),
		})
		if creditAmount >= minAmount {
			clearAntigravityCreditsPermanentlyDisabled(auth)
		}
		return
	}
}

func (e *AntigravityExecutor) buildRequest(ctx context.Context, auth *cliproxyauth.Auth, token, modelName string, payload []byte, stream bool, alt, baseURL string) (*http.Request, error) {
	if token == "" {
		return nil, statusErr{code: http.StatusUnauthorized, msg: "missing access token"}
	}

	base := strings.TrimSuffix(baseURL, "/")
	if base == "" {
		base = buildBaseURL(auth)
	}
	path := antigravityGeneratePath
	if stream {
		path = antigravityStreamPath
	}
	var requestURL strings.Builder
	requestURL.WriteString(base)
	requestURL.WriteString(path)
	if stream {
		if alt != "" {
			requestURL.WriteString("?$alt=")
			requestURL.WriteString(url.QueryEscape(alt))
		} else {
			requestURL.WriteString("?alt=sse")
		}
	} else if alt != "" {
		requestURL.WriteString("?$alt=")
		requestURL.WriteString(url.QueryEscape(alt))
	}

	// Extract project_id from auth metadata if available
	projectID := ""
	if auth != nil && auth.Metadata != nil {
		if pid, ok := auth.Metadata["project_id"].(string); ok {
			projectID = strings.TrimSpace(pid)
		}
	}
	payload = geminiToAntigravity(modelName, payload, projectID)
	payload, _ = sjson.SetBytes(payload, "model", modelName)

	// Cap maxOutputTokens to model's max_completion_tokens from registry
	if maxOut := gjson.GetBytes(payload, "request.generationConfig.maxOutputTokens"); maxOut.Exists() && maxOut.Type == gjson.Number {
		if modelInfo := registry.LookupModelInfo(modelName, "antigravity"); modelInfo != nil && modelInfo.MaxCompletionTokens > 0 {
			if int(maxOut.Int()) > modelInfo.MaxCompletionTokens {
				payload, _ = sjson.SetBytes(payload, "request.generationConfig.maxOutputTokens", modelInfo.MaxCompletionTokens)
			}
		}
	}

	useAntigravitySchema := strings.Contains(modelName, "claude") || strings.Contains(modelName, "gemini-3-pro") || strings.Contains(modelName, "gemini-3.1-pro")
	var (
		bodyReader io.Reader
		payloadLog []byte
	)
	if antigravityRequestNeedsSchemaSanitization(payload) {
		payloadStr := string(payload)
		paths := make([]string, 0)
		util.Walk(gjson.Parse(payloadStr), "", "parametersJsonSchema", &paths)
		for _, p := range paths {
			payloadStr, _ = util.RenameKey(payloadStr, p, p[:len(p)-len("parametersJsonSchema")]+"parameters")
		}

		if useAntigravitySchema {
			payloadStr = util.CleanJSONSchemaForAntigravity(payloadStr)
		} else {
			payloadStr = util.CleanJSONSchemaForGemini(payloadStr)
		}

		if strings.Contains(modelName, "claude") {
			updated, _ := sjson.SetBytes([]byte(payloadStr), "request.toolConfig.functionCallingConfig.mode", "VALIDATED")
			payloadStr = string(updated)
		} else {
			payloadStr, _ = sjson.Delete(payloadStr, "request.generationConfig.maxOutputTokens")
		}

		bodyReader = strings.NewReader(payloadStr)
		if e.cfg != nil && e.cfg.RequestLog {
			payloadLog = []byte(payloadStr)
		}
	} else {
		if strings.Contains(modelName, "claude") {
			payload, _ = sjson.SetBytes(payload, "request.toolConfig.functionCallingConfig.mode", "VALIDATED")
		} else {
			payload, _ = sjson.DeleteBytes(payload, "request.generationConfig.maxOutputTokens")
		}

		bodyReader = bytes.NewReader(payload)
		if e.cfg != nil && e.cfg.RequestLog {
			payloadLog = append([]byte(nil), payload...)
		}
	}

	// if useAntigravitySchema {
	// 	systemInstructionPartsResult := gjson.Get(payloadStr, "request.systemInstruction.parts")
	// 	payloadStr, _ = sjson.SetBytes([]byte(payloadStr), "request.systemInstruction.role", "user")
	// 	payloadStr, _ = sjson.SetBytes([]byte(payloadStr), "request.systemInstruction.parts.0.text", systemInstruction)
	// 	payloadStr, _ = sjson.SetBytes([]byte(payloadStr), "request.systemInstruction.parts.1.text", fmt.Sprintf("Please ignore following [ignore]%s[/ignore]", systemInstruction))

	// 	if systemInstructionPartsResult.Exists() && systemInstructionPartsResult.IsArray() {
	// 		for _, partResult := range systemInstructionPartsResult.Array() {
	// 			payloadStr, _ = sjson.SetRawBytes([]byte(payloadStr), "request.systemInstruction.parts.-1", []byte(partResult.Raw))
	// 		}
	// 	}
	// }

	httpReq, errReq := http.NewRequestWithContext(ctx, http.MethodPost, requestURL.String(), bodyReader)
	if errReq != nil {
		return nil, errReq
	}
	httpReq.Close = true
	httpReq.Header.Set("Content-Type", "application/json")
	httpReq.Header.Set("Authorization", "Bearer "+token)
	httpReq.Header.Set("User-Agent", resolveUserAgent(auth))
	if host := resolveHost(base); host != "" {
		httpReq.Host = host
	}
	var attrs map[string]string
	if auth != nil {
		attrs = auth.Attributes
	}
	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)

	var authID, authLabel, authType, authValue string
	if auth != nil {
		authID = auth.ID
		authLabel = auth.Label
		authType, authValue = auth.AccountInfo()
	}
	helps.RecordAPIRequest(ctx, e.cfg, helps.UpstreamRequestLog{
		URL:       requestURL.String(),
		Method:    http.MethodPost,
		Headers:   httpReq.Header.Clone(),
		Body:      payloadLog,
		Provider:  e.Identifier(),
		AuthID:    authID,
		AuthLabel: authLabel,
		AuthType:  authType,
		AuthValue: authValue,
	})

	return httpReq, nil
}

func antigravityRequestNeedsSchemaSanitization(payload []byte) bool {
	if gjson.GetBytes(payload, "request.tools.0").Exists() {
		return true
	}
	if gjson.GetBytes(payload, "request.generationConfig.responseJsonSchema").Exists() {
		return true
	}
	if gjson.GetBytes(payload, "request.generationConfig.responseSchema").Exists() {
		return true
	}
	return false
}

func tokenExpiry(metadata map[string]any) time.Time {
	if metadata == nil {
		return time.Time{}
	}
	if expStr, ok := metadata["expired"].(string); ok {
		expStr = strings.TrimSpace(expStr)
		if expStr != "" {
			if parsed, errParse := time.Parse(time.RFC3339, expStr); errParse == nil {
				return parsed
			}
		}
	}
	expiresIn, hasExpires := int64Value(metadata["expires_in"])
	tsMs, hasTimestamp := int64Value(metadata["timestamp"])
	if hasExpires && hasTimestamp {
		return time.Unix(0, tsMs*int64(time.Millisecond)).Add(time.Duration(expiresIn) * time.Second)
	}
	return time.Time{}
}

func metaStringValue(metadata map[string]any, key string) string {
	if metadata == nil {
		return ""
	}
	if v, ok := metadata[key]; ok {
		switch typed := v.(type) {
		case string:
			return strings.TrimSpace(typed)
		case []byte:
			return strings.TrimSpace(string(typed))
		}
	}
	return ""
}

func int64Value(value any) (int64, bool) {
	switch typed := value.(type) {
	case int:
		return int64(typed), true
	case int64:
		return typed, true
	case float64:
		return int64(typed), true
	case json.Number:
		if i, errParse := typed.Int64(); errParse == nil {
			return i, true
		}
	case string:
		if strings.TrimSpace(typed) == "" {
			return 0, false
		}
		if i, errParse := strconv.ParseInt(strings.TrimSpace(typed), 10, 64); errParse == nil {
			return i, true
		}
	}
	return 0, false
}

func buildBaseURL(auth *cliproxyauth.Auth) string {
	if baseURLs := antigravityBaseURLFallbackOrder(auth); len(baseURLs) > 0 {
		return baseURLs[0]
	}
	return antigravityBaseURLDaily
}

func resolveHost(base string) string {
	parsed, errParse := url.Parse(base)
	if errParse != nil {
		return ""
	}
	if parsed.Host != "" {
		return parsed.Host
	}
	return strings.TrimPrefix(strings.TrimPrefix(base, "https://"), "http://")
}

func resolveUserAgent(auth *cliproxyauth.Auth) string {
	if auth != nil {
		if auth.Attributes != nil {
			if ua := strings.TrimSpace(auth.Attributes["user_agent"]); ua != "" {
				return ua
			}
		}
		if auth.Metadata != nil {
			if ua, ok := auth.Metadata["user_agent"].(string); ok && strings.TrimSpace(ua) != "" {
				return strings.TrimSpace(ua)
			}
		}
	}
	return misc.AntigravityUserAgent()
}

func antigravityRetryAttempts(auth *cliproxyauth.Auth, cfg *config.Config) int {
	retry := 0
	if cfg != nil {
		retry = cfg.RequestRetry
	}
	if auth != nil {
		if override, ok := auth.RequestRetryOverride(); ok {
			retry = override
		}
	}
	if retry < 0 {
		retry = 0
	}
	attempts := retry + 1
	if attempts < 1 {
		return 1
	}
	return attempts
}

func antigravityShouldRetryNoCapacity(statusCode int, body []byte) bool {
	if statusCode != http.StatusServiceUnavailable {
		return false
	}
	if len(body) == 0 {
		return false
	}
	msg := strings.ToLower(string(body))
	return strings.Contains(msg, "no capacity available")
}

func antigravityShouldRetryTransientResourceExhausted429(statusCode int, body []byte) bool {
	if statusCode != http.StatusTooManyRequests {
		return false
	}
	if len(body) == 0 {
		return false
	}
	if classifyAntigravity429(body) != antigravity429Unknown {
		return false
	}
	status := strings.TrimSpace(gjson.GetBytes(body, "error.status").String())
	if !strings.EqualFold(status, "RESOURCE_EXHAUSTED") {
		return false
	}
	msg := strings.ToLower(string(body))
	return strings.Contains(msg, "resource has been exhausted")
}

func antigravityShouldRetrySoftRateLimit(statusCode int, body []byte) bool {
	if statusCode != http.StatusTooManyRequests {
		return false
	}
	return decideAntigravity429(body).kind == antigravity429DecisionSoftRetry
}

func antigravitySoftRateLimitDelay(attempt int) time.Duration {
	if attempt < 0 {
		attempt = 0
	}
	base := time.Duration(attempt+1) * 500 * time.Millisecond
	if base > 3*time.Second {
		base = 3 * time.Second
	}
	return base
}

func antigravityShortCooldownKey(auth *cliproxyauth.Auth, modelName string) string {
	if auth == nil {
		return ""
	}
	authID := strings.TrimSpace(auth.ID)
	modelName = strings.TrimSpace(modelName)
	if authID == "" || modelName == "" {
		return ""
	}
	return authID + "|" + modelName + "|sc"
}

func antigravityIsInShortCooldown(auth *cliproxyauth.Auth, modelName string, now time.Time) (bool, time.Duration) {
	key := antigravityShortCooldownKey(auth, modelName)
	if key == "" {
		return false, 0
	}
	value, ok := antigravityShortCooldownByAuth.Load(key)
	if !ok {
		return false, 0
	}
	until, ok := value.(time.Time)
	if !ok || until.IsZero() {
		antigravityShortCooldownByAuth.Delete(key)
		return false, 0
	}
	remaining := until.Sub(now)
	if remaining <= 0 {
		antigravityShortCooldownByAuth.Delete(key)
		return false, 0
	}
	return true, remaining
}

func markAntigravityShortCooldown(auth *cliproxyauth.Auth, modelName string, now time.Time, duration time.Duration) {
	key := antigravityShortCooldownKey(auth, modelName)
	if key == "" {
		return
	}
	antigravityShortCooldownByAuth.Store(key, now.Add(duration))
}

func antigravityNoCapacityRetryDelay(attempt int) time.Duration {
	if attempt < 0 {
		attempt = 0
	}
	delay := time.Duration(attempt+1) * 250 * time.Millisecond
	if delay > 2*time.Second {
		delay = 2 * time.Second
	}
	return delay
}

func antigravityTransient429RetryDelay(attempt int) time.Duration {
	if attempt < 0 {
		attempt = 0
	}
	delay := time.Duration(attempt+1) * 100 * time.Millisecond
	if delay > 500*time.Millisecond {
		delay = 500 * time.Millisecond
	}
	return delay
}

func antigravityInstantRetryDelay(wait time.Duration) time.Duration {
	if wait <= 0 {
		return 0
	}
	return wait + 800*time.Millisecond
}

func antigravityWait(ctx context.Context, wait time.Duration) error {
	if wait <= 0 {
		return nil
	}
	timer := time.NewTimer(wait)
	defer timer.Stop()
	select {
	case <-ctx.Done():
		return ctx.Err()
	case <-timer.C:
		return nil
	}
}

var antigravityBaseURLFallbackOrder = func(auth *cliproxyauth.Auth) []string {
	if base := resolveCustomAntigravityBaseURL(auth); base != "" {
		return []string{base}
	}
	return []string{
		antigravityBaseURLProd,
		antigravityBaseURLDaily,
		antigravitySandboxBaseURLDaily,
	}
}

func resolveCustomAntigravityBaseURL(auth *cliproxyauth.Auth) string {
	if auth == nil {
		return ""
	}
	if auth.Attributes != nil {
		if v := strings.TrimSpace(auth.Attributes["base_url"]); v != "" {
			return strings.TrimSuffix(v, "/")
		}
	}
	if auth.Metadata != nil {
		if v, ok := auth.Metadata["base_url"].(string); ok {
			v = strings.TrimSpace(v)
			if v != "" {
				return strings.TrimSuffix(v, "/")
			}
		}
	}
	return ""
}

func geminiToAntigravity(modelName string, payload []byte, projectID string) []byte {
	template := payload
	template, _ = sjson.SetBytes(template, "model", modelName)
	template, _ = sjson.SetBytes(template, "userAgent", "antigravity")

	isImageModel := strings.Contains(modelName, "image")

	var reqType string
	if isImageModel {
		reqType = "image_gen"
	} else {
		reqType = "agent"
	}
	template, _ = sjson.SetBytes(template, "requestType", reqType)

	// Use real project ID from auth if available, otherwise generate random (legacy fallback)
	if projectID != "" {
		template, _ = sjson.SetBytes(template, "project", projectID)
	} else {
		template, _ = sjson.SetBytes(template, "project", generateProjectID())
	}

	if isImageModel {
		template, _ = sjson.SetBytes(template, "requestId", generateImageGenRequestID())
	} else {
		template, _ = sjson.SetBytes(template, "requestId", generateRequestID())
		template, _ = sjson.SetBytes(template, "request.sessionId", generateStableSessionID(payload))
	}

	template, _ = sjson.DeleteBytes(template, "request.safetySettings")
	if toolConfig := gjson.GetBytes(template, "toolConfig"); toolConfig.Exists() && !gjson.GetBytes(template, "request.toolConfig").Exists() {
		template, _ = sjson.SetRawBytes(template, "request.toolConfig", []byte(toolConfig.Raw))
		template, _ = sjson.DeleteBytes(template, "toolConfig")
	}
	return template
}

func generateRequestID() string {
	return "agent-" + uuid.NewString()
}

func generateImageGenRequestID() string {
	return fmt.Sprintf("image_gen/%d/%s/12", time.Now().UnixMilli(), uuid.NewString())
}

func generateSessionID() string {
	randSourceMutex.Lock()
	n := randSource.Int63n(9_000_000_000_000_000_000)
	randSourceMutex.Unlock()
	return "-" + strconv.FormatInt(n, 10)
}

func generateStableSessionID(payload []byte) string {
	contents := gjson.GetBytes(payload, "request.contents")
	if contents.IsArray() {
		for _, content := range contents.Array() {
			if content.Get("role").String() == "user" {
				text := content.Get("parts.0.text").String()
				if text != "" {
					h := sha256.Sum256([]byte(text))
					n := int64(binary.BigEndian.Uint64(h[:8])) & 0x7FFFFFFFFFFFFFFF
					return "-" + strconv.FormatInt(n, 10)
				}
			}
		}
	}
	return generateSessionID()
}

func generateProjectID() string {
	adjectives := []string{"useful", "bright", "swift", "calm", "bold"}
	nouns := []string{"fuze", "wave", "spark", "flow", "core"}
	randSourceMutex.Lock()
	adj := adjectives[randSource.Intn(len(adjectives))]
	noun := nouns[randSource.Intn(len(nouns))]
	randSourceMutex.Unlock()
	randomPart := strings.ToLower(uuid.NewString())[:5]
	return adj + "-" + noun + "-" + randomPart
}