[proxy] forward Bedrock cost-allocation metadata + per-provider metadata_disabled

Stamp the caller's user and authorizing group onto AWS Bedrock requests via the
X-Amzn-Bedrock-Request-Metadata header (reusing the JSONMetadata identity-inject
shape with a Bedrock-charset sanitizer), so spend can be attributed in AWS Cost
Management. Add a per-provider metadata_disabled flag (default off) that
suppresses identity metadata injection while leaving catalog routing headers
intact.

management/internals/modules/agentnetwork/catalog/catalog.go

@@ -197,6 +197,12 @@ type JSONMetadataInjection struct {
 	// enforces a 128-char limit per value; oversized values are
 	// truncated rather than failing the request. 0 disables the cap.
 	MaxValueLength int
+	// Sanitize, when true, replaces characters outside the destination's
+	// accepted set with '_' before emitting each value. AWS Bedrock's
+	// X-Amzn-Bedrock-Request-Metadata restricts values to a limited character
+	// class, so unsanitized group display names (e.g. containing spaces) would
+	// make Bedrock reject the request with 400.
+	Sanitize bool
 }
 
 // providers is the canonical list of supported Agent Network providers.
@@ -329,6 +335,18 @@ var providers = []Provider{
 			{ID: "amazon.nova-lite", Label: "Amazon Nova Lite (Bedrock)", InputPer1k: 0.00006, OutputPer1k: 0.00024, ContextWindow: 300000},
 			{ID: "amazon.nova-micro", Label: "Amazon Nova Micro (Bedrock)", InputPer1k: 0.000035, OutputPer1k: 0.00014, ContextWindow: 128000},
 		},
+		// Bedrock accepts a cost-allocation metadata header; stamp the caller's
+		// user + authorizing group so spend can be attributed in AWS Cost
+		// Management. Sanitized because Bedrock restricts the value character set.
+		IdentityInjection: &IdentityInjection{
+			JSONMetadata: &JSONMetadataInjection{
+				Header:         "X-Amzn-Bedrock-Request-Metadata",
+				UserKey:        "user",
+				GroupsKey:      "group",
+				MaxValueLength: 256,
+				Sanitize:       true,
+			},
+		},
 	},
 	{
 		ID:                 "vertex_ai_api",

management/internals/modules/agentnetwork/synthesizer.go

@@ -540,6 +540,7 @@ type identityInjectJSONMetadata struct {
 	UserKey        string `json:"user_key,omitempty"`
 	GroupsKey      string `json:"groups_key,omitempty"`
 	MaxValueLength int    `json:"max_value_length,omitempty"`
+	Sanitize       bool   `json:"sanitize,omitempty"`
 }
 
 // buildIdentityInjectConfigJSON walks the enabled providers and emits
@@ -583,9 +584,11 @@ func buildIdentityInjectConfigJSON(providers []*types.Provider, groupIndex map[s
 func buildIdentityInjectRule(p *types.Provider, entry catalog.Provider) (identityInjectProvider, bool) {
 	rule := identityInjectProvider{ProviderID: p.ID}
 	// Identity-stamping shape (one of HeaderPair / JSONMetadata). Skip the
-	// shape silently when the catalog entry doesn't declare one — extras
-	// can still apply, see below.
-	if entry.IdentityInjection != nil {
+	// shape silently when the catalog entry doesn't declare one, or when the
+	// operator disabled metadata for this provider — extras can still apply,
+	// see below. MetadataDisabled suppresses only the identity dimensions
+	// (user + authorizing group), not the catalog's routing ExtraHeaders.
+	if !p.MetadataDisabled && entry.IdentityInjection != nil {
 		switch {
 		case entry.IdentityInjection.HeaderPair != nil:
 			rule.HeaderPair = buildIdentityHeaderPair(p, entry.IdentityInjection.HeaderPair)
@@ -651,6 +654,7 @@ func buildIdentityJSONMetadata(p *types.Provider, jm *catalog.JSONMetadataInject
 		UserKey:        userKey,
 		GroupsKey:      groupsKey,
 		MaxValueLength: jm.MaxValueLength,
+		Sanitize:       jm.Sanitize,
 	}
 }
 

management/internals/modules/agentnetwork/synthesizer_test.go

@@ -698,6 +698,94 @@ func TestSynthesizeServices_IdentityInject_Portkey_NotCustomizable(t *testing.T)
 		"same fixed-schema guarantee for the groups dimension")
 }
 
+// TestSynthesizeServices_IdentityInject_Bedrock pins Bedrock's cost-allocation
+// metadata: a JSONMetadata shape emitting X-Amzn-Bedrock-Request-Metadata with
+// the reserved user/group keys, sanitized to Bedrock's accepted charset.
+func TestSynthesizeServices_IdentityInject_Bedrock(t *testing.T) {
+	ctx := context.Background()
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+	mockStore := store.NewMockStore(ctrl)
+
+	br := newSynthTestProvider()
+	br.ID = "prov-bedrock"
+	br.ProviderID = "bedrock_api"
+	br.UpstreamURL = "https://bedrock-runtime.us-east-1.amazonaws.com"
+	br.APIKey = "bedrock-bearer"
+	br.CreatedAt = time.Date(2026, 4, 2, 0, 0, 0, 0, time.UTC)
+
+	policy := newSynthTestPolicy(br.ID, "grp-eng", "")
+	policy.ID = "pol-bedrock"
+
+	expectSynthBaseInputs(mockStore, ctx, newSynthTestSettings(),
+		[]*types.Provider{br},
+		[]*types.Policy{policy},
+		[]*types.Guardrail{})
+
+	services, err := SynthesizeServices(ctx, mockStore, testAccountID)
+	require.NoError(t, err)
+	require.Len(t, services, 1)
+
+	var injectCfg identityInjectConfig
+	for _, m := range services[0].Targets[0].Options.Middlewares {
+		if m.ID == middlewareIDLLMIdentityInject {
+			require.NoError(t, json.Unmarshal(m.ConfigJSON, &injectCfg))
+			break
+		}
+	}
+	require.Len(t, injectCfg.Providers, 1)
+	entry := injectCfg.Providers[0]
+	require.NotNil(t, entry.JSONMetadata, "Bedrock uses the JSONMetadata shape for cost-allocation metadata")
+	assert.Nil(t, entry.HeaderPair, "shapes are mutually exclusive")
+	assert.Equal(t, "X-Amzn-Bedrock-Request-Metadata", entry.JSONMetadata.Header,
+		"the caller identity lands in Bedrock's cost-allocation metadata header")
+	assert.Equal(t, "user", entry.JSONMetadata.UserKey)
+	assert.Equal(t, "group", entry.JSONMetadata.GroupsKey)
+	assert.True(t, entry.JSONMetadata.Sanitize,
+		"Bedrock restricts the metadata value charset, so values must be sanitized")
+}
+
+// TestSynthesizeServices_MetadataDisabled_SuppressesInjection verifies the
+// per-provider opt-out: a provider with MetadataDisabled set emits no
+// identity-inject entry (Bedrock has no catalog ExtraHeaders, so the whole
+// entry is dropped).
+func TestSynthesizeServices_MetadataDisabled_SuppressesInjection(t *testing.T) {
+	ctx := context.Background()
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+	mockStore := store.NewMockStore(ctrl)
+
+	br := newSynthTestProvider()
+	br.ID = "prov-bedrock"
+	br.ProviderID = "bedrock_api"
+	br.UpstreamURL = "https://bedrock-runtime.us-east-1.amazonaws.com"
+	br.APIKey = "bedrock-bearer"
+	br.MetadataDisabled = true
+	br.CreatedAt = time.Date(2026, 4, 2, 0, 0, 0, 0, time.UTC)
+
+	policy := newSynthTestPolicy(br.ID, "grp-eng", "")
+	policy.ID = "pol-bedrock"
+
+	expectSynthBaseInputs(mockStore, ctx, newSynthTestSettings(),
+		[]*types.Provider{br},
+		[]*types.Policy{policy},
+		[]*types.Guardrail{})
+
+	services, err := SynthesizeServices(ctx, mockStore, testAccountID)
+	require.NoError(t, err)
+	require.Len(t, services, 1)
+
+	var injectCfg identityInjectConfig
+	for _, m := range services[0].Targets[0].Options.Middlewares {
+		if m.ID == middlewareIDLLMIdentityInject {
+			require.NoError(t, json.Unmarshal(m.ConfigJSON, &injectCfg))
+			break
+		}
+	}
+	assert.Empty(t, injectCfg.Providers,
+		"metadata_disabled must drop the provider's identity-inject entry")
+}
+
 // TestSynthesizeServices_IdentityInject_Vercel pins Vercel AI
 // Gateway's wiring: HeaderPair shape with fixed wire names dictated
 // by Vercel's Custom Reporting API (ai-reporting-user /

management/internals/modules/agentnetwork/types/provider.go

@@ -51,6 +51,12 @@ type Provider struct {
 	// private or self-signed certificate. The synthesiser propagates it into
 	// the router route so the proxy dials that provider's upstream insecurely.
 	SkipTLSVerification bool `gorm:"column:skip_tls_verification"`
+	// MetadataDisabled suppresses identity metadata injection for this provider.
+	// Metadata (the caller's user + authorizing group) is injected by default;
+	// when true the synthesiser omits the provider's identity-inject shape, so no
+	// user/group headers (e.g. Bedrock's X-Amzn-Bedrock-Request-Metadata) are
+	// stamped. Catalog ExtraHeaders (routing config) are unaffected.
+	MetadataDisabled bool `gorm:"column:metadata_disabled"`
 	// SessionPrivateKey + SessionPublicKey are the ed25519 keypair the
 	// synthesised reverse-proxy service uses to sign / verify session
 	// JWTs after a successful OIDC handshake. Generated once on
@@ -137,6 +143,9 @@ func (p *Provider) FromAPIRequest(req *api.AgentNetworkProviderRequest) {
 	if req.SkipTlsVerification != nil {
 		p.SkipTLSVerification = *req.SkipTlsVerification
 	}
+	if req.MetadataDisabled != nil {
+		p.MetadataDisabled = *req.MetadataDisabled
+	}
 	// Identity-header overrides for catalogs flagged Customizable.
 	// nil pointer = "field omitted on the wire" → leave the stored
 	// value untouched (per the openapi description). Empty string is
@@ -170,6 +179,7 @@ func (p *Provider) ToAPIResponse() *api.AgentNetworkProvider {
 		Models:              models,
 		Enabled:             p.Enabled,
 		SkipTlsVerification: p.SkipTLSVerification,
+		MetadataDisabled:    p.MetadataDisabled,
 		CreatedAt:           &created,
 		UpdatedAt:           &updated,
 	}

management/internals/modules/agentnetwork/types/provider_test.go

@@ -42,3 +42,38 @@ func TestProvider_SkipTLSVerification_RoundTrip(t *testing.T) {
 	assert.False(t, p.SkipTLSVerification, "explicit false must clear skip_tls_verification")
 	assert.False(t, p.ToAPIResponse().SkipTlsVerification, "response must reflect the cleared value")
 }
+
+// TestProvider_MetadataDisabled_RoundTrip covers the request→provider→response
+// mapping of metadata_disabled, with the same update semantics: nil preserves,
+// explicit false clears.
+func TestProvider_MetadataDisabled_RoundTrip(t *testing.T) {
+	enable := true
+	disable := false
+
+	base := func() *api.AgentNetworkProviderRequest {
+		return &api.AgentNetworkProviderRequest{
+			ProviderId:  "bedrock_api",
+			Name:        "bedrock",
+			UpstreamUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
+		}
+	}
+
+	p := NewProvider("acc-1")
+
+	req := base()
+	req.MetadataDisabled = &enable
+	p.FromAPIRequest(req)
+	assert.True(t, p.MetadataDisabled, "create with metadata_disabled=true must set the field")
+	assert.True(t, p.ToAPIResponse().MetadataDisabled, "response must surface metadata_disabled")
+
+	// Omitting the field on update leaves the stored value untouched.
+	p.FromAPIRequest(base())
+	assert.True(t, p.MetadataDisabled, "omitting metadata_disabled on update must preserve it")
+
+	// Explicit false clears it (re-enables metadata).
+	req = base()
+	req.MetadataDisabled = &disable
+	p.FromAPIRequest(req)
+	assert.False(t, p.MetadataDisabled, "explicit false must clear metadata_disabled")
+	assert.False(t, p.ToAPIResponse().MetadataDisabled, "response must reflect the cleared value")
+}

proxy/internal/middleware/builtin/llm_identity_inject/factory.go

@@ -64,6 +64,11 @@ type JSONMetadataRule struct {
 	UserKey        string `json:"user_key,omitempty"`
 	GroupsKey      string `json:"groups_key,omitempty"`
 	MaxValueLength int    `json:"max_value_length,omitempty"`
+	// Sanitize replaces characters outside the destination provider's accepted
+	// set with '_' before emitting each value. AWS Bedrock's
+	// X-Amzn-Bedrock-Request-Metadata restricts values to [A-Za-z0-9 +-=._:/@];
+	// group display names with other characters would otherwise 400.
+	Sanitize bool `json:"sanitize,omitempty"`
 }
 
 // Config is the on-wire configuration accepted by the factory. An

proxy/internal/middleware/builtin/llm_identity_inject/middleware.go

@@ -292,15 +292,21 @@ func applyJSONMetadata(rule *JSONMetadataRule, in *middleware.Input) *middleware
 	mutations := &middleware.Mutations{}
 	mutations.HeadersRemove = append(mutations.HeadersRemove, rule.Header)
 
+	emit := func(v string) string {
+		if rule.Sanitize {
+			v = sanitizeMetadataValue(v)
+		}
+		return truncate(v, rule.MaxValueLength)
+	}
 	payload := map[string]string{}
 	if rule.UserKey != "" {
 		if identity := identityFor(in); identity != "" {
-			payload[rule.UserKey] = truncate(identity, rule.MaxValueLength)
+			payload[rule.UserKey] = emit(identity)
 		}
 	}
 	if rule.GroupsKey != "" {
 		if csv := authorisingTagsCSV(in); csv != "" {
-			payload[rule.GroupsKey] = truncate(csv, rule.MaxValueLength)
+			payload[rule.GroupsKey] = emit(csv)
 		}
 	}
 	if len(payload) == 0 {
@@ -359,6 +365,36 @@ func truncate(s string, maxBytes int) string {
 	return s[:maxBytes]
 }
 
+// sanitizeMetadataValue replaces any character outside AWS Bedrock's accepted
+// request-metadata class — letters, digits, space, and + - = . _ : / @ — with
+// '_'. This keeps values (notably the groups CSV, whose commas are rejected, and
+// group display names with arbitrary characters) from making Bedrock reject the
+// request with 400. The result stays opaque to the gateway.
+func sanitizeMetadataValue(s string) string {
+	var b strings.Builder
+	b.Grow(len(s))
+	for _, r := range s {
+		if metadataCharAllowed(r) {
+			b.WriteRune(r)
+		} else {
+			b.WriteByte('_')
+		}
+	}
+	return b.String()
+}
+
+func metadataCharAllowed(r rune) bool {
+	switch {
+	case r >= 'a' && r <= 'z', r >= 'A' && r <= 'Z', r >= '0' && r <= '9':
+		return true
+	}
+	switch r {
+	case ' ', '+', '-', '=', '.', '_', ':', '/', '@':
+		return true
+	}
+	return false
+}
+
 // tagsIDsFromAuthorising reads llm_router's authorising-groups metadata
 // (a CSV of group ids) and returns the parsed slice. Returns nil when
 // the key is absent or empty so the caller can fall back to the full

proxy/internal/middleware/builtin/llm_identity_inject/middleware_test.go

@@ -304,6 +304,46 @@ func TestInject_JSONMetadata_TruncatesValues(t *testing.T) {
 		"per-value byte length must be capped at MaxValueLength")
 }
 
+// TestInject_JSONMetadata_Sanitize pins the AWS-Bedrock sanitization path: when
+// Sanitize is set, characters outside Bedrock's accepted metadata class
+// (notably the groups CSV comma and arbitrary characters in group display
+// names) are replaced with '_' so Bedrock doesn't reject the request. Allowed
+// characters (letters, digits, spaces, and @ . _ : / + - =) pass through.
+func TestInject_JSONMetadata_Sanitize(t *testing.T) {
+	rule := ProviderInjection{
+		ProviderID: portkeyProvider,
+		JSONMetadata: &JSONMetadataRule{
+			Header:         "X-Amzn-Bedrock-Request-Metadata",
+			UserKey:        "user",
+			GroupsKey:      "group",
+			MaxValueLength: 256,
+			Sanitize:       true,
+		},
+	}
+	mw := New(Config{Providers: []ProviderInjection{rule}})
+	in := newInput(portkeyProvider, "alice", []string{"g1", "g2"})
+	in.UserEmail = "alice@example.com"
+	// Group display names carry characters Bedrock rejects (comma, '#'); the CSV
+	// join adds another comma between the two groups.
+	in.UserGroupNames = []string{"Eng,Team", "Ops#1"}
+
+	out, err := mw.Invoke(context.Background(), in)
+	require.NoError(t, err)
+	require.NotNil(t, out.Mutations)
+	require.Len(t, out.Mutations.HeadersAdd, 1)
+	added := out.Mutations.HeadersAdd[0]
+	assert.Equal(t, "X-Amzn-Bedrock-Request-Metadata", added.Key,
+		"the Bedrock cost-allocation header carries the metadata JSON")
+
+	var payload map[string]string
+	require.NoError(t, json.Unmarshal([]byte(added.Value), &payload))
+	assert.Equal(t, "alice@example.com", payload["user"],
+		"'@' and '.' are in Bedrock's accepted set and must be preserved")
+	assert.NotContains(t, payload["group"], ",", "commas must be sanitized — Bedrock rejects them")
+	assert.NotContains(t, payload["group"], "#", "disallowed characters must be sanitized")
+	assert.Contains(t, payload["group"], "Eng", "allowed characters must be preserved")
+}
+
 // TestInject_JSONMetadata_EmptyIdentity_StripsButDoesNotAdd verifies the
 // anti-spoof Remove still fires when there's nothing to stamp.
 func TestInject_JSONMetadata_EmptyIdentity_StripsButDoesNotAdd(t *testing.T) {

shared/management/http/api/openapi.yml

@@ -5164,6 +5164,10 @@ components:
           type: boolean
           description: Whether upstream TLS certificate verification is skipped when the proxy dials this provider's URL. Intended for self-hosted / internal gateways behind a private or self-signed certificate.
           example: false
+        metadata_disabled:
+          type: boolean
+          description: Whether identity metadata injection is disabled for this provider. When enabled (the default), the proxy stamps the caller's user and authorizing group onto upstream requests as provider-specific metadata (e.g. AWS Bedrock's X-Amzn-Bedrock-Request-Metadata header). Set true to suppress it.
+          example: false
         created_at:
           type: string
           format: date-time
@@ -5184,6 +5188,7 @@ components:
         - models
         - enabled
         - skip_tls_verification
+        - metadata_disabled
         - created_at
         - updated_at
     AgentNetworkProviderRequest:
@@ -5240,6 +5245,10 @@ components:
           type: boolean
           description: Skip upstream TLS certificate verification when the proxy dials this provider's URL. For self-hosted / internal gateways behind a private or self-signed certificate. Defaults to false. When omitted on update, the stored value is left unchanged.
           example: false
+        metadata_disabled:
+          type: boolean
+          description: Disable identity metadata injection (the caller's user + authorizing group) for this provider. Defaults to false (metadata is injected). When omitted on update, the stored value is left unchanged.
+          example: false
       required:
         - provider_id
         - name

shared/management/http/api/types.gen.go

@@ -2227,6 +2227,9 @@ type AgentNetworkProvider struct {
 	// IdentityHeaderUserId Wire header name the proxy stamps with the caller's display identity (user email or peer name) when the catalog entry's HeaderPair is `customizable`. Empty disables stamping for this dimension. Ignored when the catalog entry has a fixed HeaderPair (e.g. LiteLLM, Portkey). Used today by Bifrost: typical values are `x-bf-lh-netbird_user_id` (always-on log metadata) or `x-bf-dim-netbird_user_id` (Prometheus / OTEL — requires the label to be pre-declared in the gateway's `client.prometheus_labels` config).
 	IdentityHeaderUserId *string `json:"identity_header_user_id,omitempty"`
 
+	// MetadataDisabled Whether identity metadata injection is disabled for this provider. When enabled (the default), the proxy stamps the caller's user and authorizing group onto upstream requests as provider-specific metadata (e.g. AWS Bedrock's X-Amzn-Bedrock-Request-Metadata header). Set true to suppress it.
+	MetadataDisabled bool `json:"metadata_disabled"`
+
 	// Models Models exposed through this endpoint, with the operator's per-1k input/output prices. Empty means all catalog models are allowed at catalog prices.
 	Models []AgentNetworkProviderModel `json:"models"`
 
@@ -2278,6 +2281,9 @@ type AgentNetworkProviderRequest struct {
 	// IdentityHeaderUserId Wire header name for the caller's display identity. See AgentNetworkProvider.identity_header_user_id. When omitted on a request, the stored value is left unchanged; pass an empty string explicitly to clear it (which disables stamping for this dimension).
 	IdentityHeaderUserId *string `json:"identity_header_user_id,omitempty"`
 
+	// MetadataDisabled Disable identity metadata injection (the caller's user + authorizing group) for this provider. Defaults to false (metadata is injected). When omitted on update, the stored value is left unchanged.
+	MetadataDisabled *bool `json:"metadata_disabled,omitempty"`
+
 	// Models Models exposed through this endpoint, with the operator's per-1k input/output prices. Empty means all catalog models are allowed at catalog prices.
 	Models *[]AgentNetworkProviderModel `json:"models,omitempty"`