diff --git a/internal/adapter/common/blocks.go b/internal/adapter/common/blocks.go
index 5823b35..9330eac 100644
--- a/internal/adapter/common/blocks.go
+++ b/internal/adapter/common/blocks.go
@@ -1,7 +1,14 @@
 // Package common provides shared helpers for harness adapters.
 package common
 
-import "github.com/lukaszraczylo/harness-sync/internal/canonical"
+import (
+	"encoding/json"
+	"strings"
+
+	"github.com/lukaszraczylo/harness-sync/internal/canonical"
+)
+
+const gatewayProviderID = "harness-sync-gateway"
 
 // ProviderEntry is a generic provider record. Adapters may massage further.
 type ProviderEntry = map[string]any
@@ -13,7 +20,7 @@ func BuildProviders(p *canonical.Profile) []ProviderEntry {
 	out := make([]ProviderEntry, 0, len(p.Upstreams)+1)
 	if p.Gateway.URL != "" {
 		gw := ProviderEntry{
-			"id":       "harness-sync-gateway",
+			"id":       gatewayProviderID,
 			"name":     "harness-sync gateway",
 			"base_url": p.Gateway.URL,
 			"api_key":  p.Gateway.Token,
@@ -48,30 +55,81 @@ func buildModels(models []canonical.Model) []map[string]any {
 	return out
 }
 
+// crushModel builds a 10-field model entry required by the crush schema.
+func crushModel(id string) map[string]any {
+	return map[string]any{
+		"id":                     id,
+		"name":                   id,
+		"cost_per_1m_in":         0,
+		"cost_per_1m_out":        0,
+		"cost_per_1m_in_cached":  0,
+		"cost_per_1m_out_cached": 0,
+		"context_window":         200000,
+		"default_max_tokens":     8192,
+		"can_reason":             false,
+		"supports_attachments":   true,
+	}
+}
+
+// ProvidersAsCrushMap returns a map[providerID]providerObject for the crush
+// harness. Each provider has type, base_url, api_key, and models[].
+// models[] entries carry all 10 required crush schema fields.
+func ProvidersAsCrushMap(p *canonical.Profile) map[string]any {
+	out := map[string]any{}
+	if p.Gateway.URL == "" {
+		return out
+	}
+	models := make([]map[string]any, 0)
+	for _, m := range p.Models {
+		models = append(models, crushModel(m.ID))
+	}
+	if len(models) == 0 && p.Gateway.DefaultModel != "" {
+		models = append(models, crushModel(p.Gateway.DefaultModel))
+	}
+	out[gatewayProviderID] = map[string]any{
+		"type":     "openai-compat",
+		"base_url": p.Gateway.URL,
+		"api_key":  p.Gateway.Token,
+		"models":   models,
+	}
+	return out
+}
+
+// CrushRoleModels returns the top-level models map for crush with large, small,
+// and title roles all pointing at the gateway provider + default model.
+func CrushRoleModels(p *canonical.Profile) map[string]any {
+	if p.Gateway.DefaultModel == "" {
+		return map[string]any{}
+	}
+	sel := map[string]any{
+		"model":    p.Gateway.DefaultModel,
+		"provider": gatewayProviderID,
+	}
+	return map[string]any{
+		"large": sel,
+		"small": sel,
+		"title": sel,
+	}
+}
+
 // ProvidersAsMap returns a name-keyed map of provider objects for harnesses
-// like opencode that use `provider` (singular, map-shaped) instead of a slice.
-// The gateway entry is keyed "harness-sync-gateway"; upstreams use their name.
+// like opencode/kilo that use `provider` (singular, map-shaped) instead of a
+// slice. Each entry has npm + options.{baseURL,apiKey} per the opencode schema.
 func ProvidersAsMap(p *canonical.Profile) map[string]any {
 	out := map[string]any{}
 	if p.Gateway.URL != "" {
-		entry := map[string]any{
-			"name": "harness-sync gateway",
+		out[gatewayProviderID] = map[string]any{
+			"npm": "@ai-sdk/openai-compatible",
 			"options": map[string]any{
 				"baseURL": p.Gateway.URL,
 				"apiKey":  p.Gateway.Token,
 			},
 		}
-		if models := buildModels(p.Models); len(models) > 0 {
-			modelsMap := map[string]any{}
-			for _, m := range p.Models {
-				modelsMap[m.ID] = map[string]any{"name": m.ID}
-			}
-			entry["models"] = modelsMap
-		}
-		out["harness-sync-gateway"] = entry
 	}
 	for _, up := range p.Upstreams {
-		entry := map[string]any{"name": up.Name}
+		entry := map[string]any{
+			"npm": "@ai-sdk/openai-compatible",
+		}
 		opts := map[string]any{}
 		if up.BaseURL != "" {
 			opts["baseURL"] = up.BaseURL
@@ -87,6 +145,121 @@ func ProvidersAsMap(p *canonical.Profile) map[string]any {
 	return out
 }
 
+// KiloModelString returns the "providerID/modelID" string used by kilo/opencode.
+func KiloModelString(p *canonical.Profile) string {
+	if p.Gateway.DefaultModel == "" {
+		return ""
+	}
+	return gatewayProviderID + "/" + p.Gateway.DefaultModel
+}
+
+// ProvidersAsCagentMap returns the providers block for cagent:
+// map[providerID]{base_url, token_key, provider}.
+func ProvidersAsCagentMap(p *canonical.Profile) map[string]any {
+	out := map[string]any{}
+	if p.Gateway.URL == "" {
+		return out
+	}
+	out[gatewayProviderID] = map[string]any{
+		"base_url":  p.Gateway.URL,
+		"token_key": "HARNESS_SYNC_GATEWAY_TOKEN",
+		"provider":  "openai",
+	}
+	return out
+}
+
+// ZedLanguageModels returns the language_models.openai block for Zed when a
+// gateway URL is configured.
+func ZedLanguageModels(p *canonical.Profile) map[string]any {
+	if p.Gateway.URL == "" {
+		return map[string]any{}
+	}
+	models := make([]map[string]any, 0)
+	for _, m := range p.Models {
+		models = append(models, map[string]any{
+			"name": m.ID,
+			"display_name": func() string {
+				if m.Alias != "" {
+					return m.Alias
+				}
+				return m.ID
+			}(),
+			"max_tokens": 8192,
+		})
+	}
+	if len(models) == 0 && p.Gateway.DefaultModel != "" {
+		models = append(models, map[string]any{
+			"name":         p.Gateway.DefaultModel,
+			"display_name": p.Gateway.DefaultModel,
+			"max_tokens":   8192,
+		})
+	}
+	return map[string]any{
+		"openai": map[string]any{
+			"api_url":          p.Gateway.URL,
+			"available_models": models,
+		},
+	}
+}
+
+// GooseCustomProviderFile returns the JSON body and provider ID for the goose
+// custom_providers/<id>.json file. Returns nil body when Gateway.URL is empty.
+func GooseCustomProviderFile(p *canonical.Profile) ([]byte, string) {
+	if p.Gateway.URL == "" {
+		return nil, ""
+	}
+	providerID := gatewayProviderID
+	providerName := "custom_" + providerID
+
+	models := make([]map[string]any, 0)
+	for _, m := range p.Models {
+		models = append(models, map[string]any{
+			"name":          m.ID,
+			"context_limit": 200000,
+		})
+	}
+	if len(models) == 0 && p.Gateway.DefaultModel != "" {
+		// strip optional "provider/" prefix from DefaultModel
+		modelID := p.Gateway.DefaultModel
+		if idx := strings.IndexByte(modelID, '/'); idx >= 0 {
+			modelID = modelID[idx+1:]
+		}
+		models = append(models, map[string]any{
+			"name":          modelID,
+			"context_limit": 200000,
+		})
+	}
+
+	// display_name: hostname of the gateway URL, or just providerID.
+	displayName := providerID
+	if idx := strings.Index(p.Gateway.URL, "://"); idx >= 0 {
+		rest := p.Gateway.URL[idx+3:]
+		if slash := strings.IndexByte(rest, '/'); slash >= 0 {
+			rest = rest[:slash]
+		}
+		if rest != "" {
+			displayName = rest
+		}
+	}
+
+	chatURL := strings.TrimRight(p.Gateway.URL, "/") + "/v1/chat/completions"
+
+	entry := map[string]any{
+		"name":          providerName,
+		"engine":        "openai",
+		"display_name":  displayName,
+		"base_url":      chatURL,
+		"models":        models,
+		"requires_auth": true,
+		"api_key_env":   "CUSTOM_HARNESS_SYNC_GATEWAY_API_KEY",
+	}
+	body, err := json.MarshalIndent(entry, "", "  ")
+	if err != nil {
+		return nil, ""
+	}
+	return body, providerName
+}
+
 // BuildMCPMap returns canonical MCP servers as a name -> object map.
 // Empty map (not nil) is returned when there are no servers so the caller
 // can decide whether to include the key.
diff --git a/internal/adapters/cagent/cagent.go b/internal/adapters/cagent/cagent.go
index 8698e2f..ae16489 100644
--- a/internal/adapters/cagent/cagent.go
+++ b/internal/adapters/cagent/cagent.go
@@ -10,6 +10,7 @@ import (
 	"path/filepath"
 
 	"github.com/lukaszraczylo/harness-sync/internal/adapter"
+	"github.com/lukaszraczylo/harness-sync/internal/adapter/common"
 	"github.com/lukaszraczylo/harness-sync/internal/canonical"
 
 	"gopkg.in/yaml.v3"
@@ -76,6 +77,12 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 		mcps[s.Name] = e
 	}
 
+	// inline model shorthand: "providerID/modelID"
+	modelRef := ""
+	if b.Profile.Gateway.DefaultModel != "" {
+		modelRef = "harness-sync-gateway/" + b.Profile.Gateway.DefaultModel
+	}
+
 	cfg := map[string]any{
 		"version": 8,
 		"metadata": map[string]any{
@@ -83,14 +90,15 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 		},
 		"agents": map[string]any{
 			"default": map[string]any{
-				"model":       "gateway/" + b.Profile.Gateway.DefaultModel,
+				"model":       modelRef,
 				"instruction": instructions,
 			},
 		},
+		"providers": common.ProvidersAsCagentMap(&b.Profile),
 		"models": map[string]any{
-			"gateway": map[string]any{
-				"provider": "openai", // cagent gateway via openai-compat
-				"base_url": b.Profile.Gateway.URL,
+			"harness-sync-gateway": map[string]any{
+				"provider": "harness-sync-gateway",
+				"model":    b.Profile.Gateway.DefaultModel,
 			},
 		},
 	}
diff --git a/internal/adapters/cagent/cagent_test.go b/internal/adapters/cagent/cagent_test.go
index fa2d3b3..0fa267f 100644
--- a/internal/adapters/cagent/cagent_test.go
+++ b/internal/adapters/cagent/cagent_test.go
@@ -48,19 +48,63 @@ func TestCagentRenderProducesExpectedTargets(t *testing.T) {
 
 	agents := parsed["agents"].(map[string]any)
 	def := agents["default"].(map[string]any)
-	assert.Equal(t, "gateway/claude-sonnet-4-6", def["model"])
+	assert.Equal(t, "harness-sync-gateway/claude-sonnet-4-6", def["model"])
 	assert.Contains(t, def["instruction"], "# global instruction")
 
+	// providers map (new schema).
+	providers := parsed["providers"].(map[string]any)
+	gwProv := providers["harness-sync-gateway"].(map[string]any)
+	assert.Equal(t, "https://gw", gwProv["base_url"])
+	assert.Equal(t, "HARNESS_SYNC_GATEWAY_TOKEN", gwProv["token_key"])
+	assert.Equal(t, "openai", gwProv["provider"])
+
+	// models map.
 	models := parsed["models"].(map[string]any)
-	gw := models["gateway"].(map[string]any)
-	assert.Equal(t, "openai", gw["provider"])
-	assert.Equal(t, "https://gw", gw["base_url"])
+	gw := models["harness-sync-gateway"].(map[string]any)
+	assert.Equal(t, "harness-sync-gateway", gw["provider"])
+	assert.Equal(t, "claude-sonnet-4-6", gw["model"])
 
 	mcps := parsed["mcps"].(map[string]any)
 	fp := mcps["filepuff"].(map[string]any)
 	assert.Equal(t, "/bin/filepuff", fp["command"])
 }
 
+func TestCagentRenderProvidersAndModelsMaps(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Profile: canonical.Profile{
+			Gateway: canonical.Gateway{
+				URL:          "https://gw",
+				Token:        "tok",
+				DefaultModel: "claude-sonnet-4-6",
+			},
+		},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	cfgDest := filepath.Join(home, ".config", "cagent", "default.yaml")
+	var parsed map[string]any
+	require.NoError(t, yaml.Unmarshal(seen[cfgDest].Content, &parsed))
+
+	// providers block present.
+	providers, ok := parsed["providers"].(map[string]any)
+	require.True(t, ok, "providers must be a map")
+	gw, ok := providers["harness-sync-gateway"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "https://gw", gw["base_url"])
+	assert.Equal(t, "HARNESS_SYNC_GATEWAY_TOKEN", gw["token_key"])
+	assert.Equal(t, "openai", gw["provider"])
+
+	// agents.default.model uses inline shorthand.
+	agents := parsed["agents"].(map[string]any)
+	def := agents["default"].(map[string]any)
+	assert.Equal(t, "harness-sync-gateway/claude-sonnet-4-6", def["model"])
+}
+
 func TestCagentRenderNoMCP(t *testing.T) {
 	home := t.TempDir()
 	ad := New(WithHome(home))
diff --git a/internal/adapters/claudecode/claudecode.go b/internal/adapters/claudecode/claudecode.go
index 76869f7..b41ad5c 100644
--- a/internal/adapters/claudecode/claudecode.go
+++ b/internal/adapters/claudecode/claudecode.go
@@ -78,6 +78,29 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 		Content: []byte(instructions),
 	})
 
+	// settings.json holds the gateway env vars + model override.
+	// Only emit when a gateway URL is configured.
+	if b.Profile.Gateway.URL != "" {
+		settingsPath := filepath.Join(base, "settings.json")
+		settingsExisting, _ := os.ReadFile(settingsPath)
+		settingsOverlay := map[string]any{
+			"model": b.Profile.Gateway.DefaultModel,
+			"env": map[string]any{
+				"ANTHROPIC_BASE_URL":   b.Profile.Gateway.URL,
+				"ANTHROPIC_AUTH_TOKEN": b.Profile.Gateway.Token,
+			},
+		}
+		settingsMerged, err := common.MergeJSONKeys(settingsExisting, settingsOverlay)
+		if err != nil {
+			return nil, err
+		}
+		fs.Add(adapter.File{
+			Dest:    settingsPath,
+			Kind:    adapter.RenderedFile,
+			Content: settingsMerged,
+		})
+	}
+
 	// Claude Code reads MCP servers from two files on disk:
 	//   * ~/.claude.json (live, written by `claude mcp add`)
 	//   * ~/.claude/mcp_servers.json (older / fallback location)
diff --git a/internal/adapters/claudecode/claudecode_test.go b/internal/adapters/claudecode/claudecode_test.go
index 16b7828..6b705e5 100644
--- a/internal/adapters/claudecode/claudecode_test.go
+++ b/internal/adapters/claudecode/claudecode_test.go
@@ -94,6 +94,53 @@ func TestRenderMergesLiveClaudeJSON(t *testing.T) {
 	assert.Equal(t, "stdio", fp["type"])
 }
 
+func TestClaudeCodeRenderSetsAnthropicBaseURLInSettings(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Root: "/canon",
+		Profile: canonical.Profile{
+			Gateway: canonical.Gateway{
+				URL:          "https://gw",
+				Token:        "tok",
+				DefaultModel: "claude-sonnet-4-6",
+			},
+		},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	settingsDest := filepath.Join(home, ".claude", "settings.json")
+	require.Contains(t, seen, settingsDest)
+	assert.Equal(t, adapter.RenderedFile, seen[settingsDest].Kind)
+
+	var parsed map[string]any
+	require.NoError(t, json.Unmarshal(seen[settingsDest].Content, &parsed))
+	assert.Equal(t, "claude-sonnet-4-6", parsed["model"])
+	env, ok := parsed["env"].(map[string]any)
+	require.True(t, ok, "env must be a map")
+	assert.Equal(t, "https://gw", env["ANTHROPIC_BASE_URL"])
+	assert.Equal(t, "tok", env["ANTHROPIC_AUTH_TOKEN"])
+}
+
+func TestClaudeCodeRenderNoGatewayNoSettings(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Root:    "/canon",
+		Profile: canonical.Profile{},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	settingsDest := filepath.Join(home, ".claude", "settings.json")
+	assert.NotContains(t, seen, settingsDest, "settings.json must not be written when no gateway URL")
+}
+
 func TestImport(t *testing.T) {
 	home := t.TempDir()
 	base := filepath.Join(home, ".claude")
diff --git a/internal/adapters/crush/crush.go b/internal/adapters/crush/crush.go
index 0b2f581..d1d27a5 100644
--- a/internal/adapters/crush/crush.go
+++ b/internal/adapters/crush/crush.go
@@ -62,9 +62,12 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 
 	cfgPath := filepath.Join(base, "crush.json")
 	existing, _ := os.ReadFile(cfgPath)
-	overlay := map[string]any{
-		"providers":     common.BuildProviders(&b.Profile),
-		"default_model": b.Profile.Gateway.DefaultModel,
+	overlay := map[string]any{}
+	if providers := common.ProvidersAsCrushMap(&b.Profile); len(providers) > 0 {
+		overlay["providers"] = providers
+	}
+	if roleModels := common.CrushRoleModels(&b.Profile); len(roleModels) > 0 {
+		overlay["models"] = roleModels
 	}
 	if mcp := common.BuildMCPMapStyled(&b.MCP, common.MCPCrushStyle); len(mcp) > 0 {
 		overlay["mcp"] = mcp
diff --git a/internal/adapters/crush/crush_test.go b/internal/adapters/crush/crush_test.go
index 343c955..3144a9e 100644
--- a/internal/adapters/crush/crush_test.go
+++ b/internal/adapters/crush/crush_test.go
@@ -41,9 +41,20 @@ func TestCrushRenderProducesExpectedTargets(t *testing.T) {
 	var parsed map[string]any
 	require.NoError(t, json.Unmarshal(seen[cfgDest].Content, &parsed))
 	assert.NotNil(t, parsed)
-	// Must use "default_model", not "model".
-	assert.Contains(t, parsed, "default_model")
-	// Must not write "mcpServers" — crush uses "mcp".
+	// providers must be a map (not array), keyed by providerID.
+	providers, ok := parsed["providers"].(map[string]any)
+	require.True(t, ok, "providers must be a map")
+	gw, ok := providers["harness-sync-gateway"].(map[string]any)
+	require.True(t, ok, "harness-sync-gateway provider missing")
+	assert.Equal(t, "openai-compat", gw["type"])
+	// models must be role-map with large/small/title.
+	models, ok := parsed["models"].(map[string]any)
+	require.True(t, ok, "models must be a map")
+	assert.Contains(t, models, "large")
+	assert.Contains(t, models, "small")
+	assert.Contains(t, models, "title")
+	// Must NOT write "default_model" or "mcpServers".
+	assert.NotContains(t, parsed, "default_model")
 	assert.NotContains(t, parsed, "mcpServers")
 }
 
@@ -105,6 +116,54 @@ func TestCrushRenderMergesExistingKeys(t *testing.T) {
 	assert.Contains(t, parsed, "lsp")
 	assert.Contains(t, parsed, "permissions")
 }
+func TestCrushRenderProducesMapProvidersAndRoleModels(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Profile: canonical.Profile{
+			Gateway: canonical.Gateway{URL: "https://gw", Token: "tok", DefaultModel: "claude-sonnet-4-6"},
+			Models:  []canonical.Model{{ID: "claude-sonnet-4-6"}},
+		},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	cfgDest := filepath.Join(home, ".config", "crush", "crush.json")
+	var parsed map[string]any
+	require.NoError(t, json.Unmarshal(seen[cfgDest].Content, &parsed))
+
+	// providers is a map, not an array.
+	providers, ok := parsed["providers"].(map[string]any)
+	require.True(t, ok, "providers must be a map")
+	gw, ok := providers["harness-sync-gateway"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "openai-compat", gw["type"])
+	assert.Equal(t, "https://gw", gw["base_url"])
+	provModels, ok := gw["models"].([]any)
+	require.True(t, ok, "models must be array inside provider")
+	require.Len(t, provModels, 1)
+	m0 := provModels[0].(map[string]any)
+	assert.Equal(t, "claude-sonnet-4-6", m0["id"])
+	// All 10 required fields present.
+	for _, field := range []string{"id", "name", "cost_per_1m_in", "cost_per_1m_out",
+		"cost_per_1m_in_cached", "cost_per_1m_out_cached", "context_window",
+		"default_max_tokens", "can_reason", "supports_attachments"} {
+		assert.Contains(t, m0, field, "missing field %s", field)
+	}
+
+	// top-level models is role-map.
+	roleModels, ok := parsed["models"].(map[string]any)
+	require.True(t, ok)
+	for _, role := range []string{"large", "small", "title"} {
+		sel, ok := roleModels[role].(map[string]any)
+		require.True(t, ok, "role %s missing", role)
+		assert.Equal(t, "claude-sonnet-4-6", sel["model"])
+		assert.Equal(t, "harness-sync-gateway", sel["provider"])
+	}
+}
+
 func TestCrushImportRoundtrip(t *testing.T) {
 	home := t.TempDir()
 	base := filepath.Join(home, ".config", "crush")
diff --git a/internal/adapters/goose/goose.go b/internal/adapters/goose/goose.go
index 9a373d7..ccd77f5 100644
--- a/internal/adapters/goose/goose.go
+++ b/internal/adapters/goose/goose.go
@@ -4,9 +4,9 @@
 // MCP-equivalent servers go under "extensions" (not "mcp").
 // Model is split into GOOSE_PROVIDER + GOOSE_MODEL.
 //
-// Custom provider files (~/.config/goose/custom_providers/<name>.yaml) are
-// out of v1 scope. If a gateway URL is configured we set GOOSE_PROVIDER to
-// signal the intent; the user must hand-write the custom_providers file.
+// When a gateway URL is configured we:
+//   - Write ~/.config/goose/custom_providers/<providerName>.json
+//   - Set GOOSE_PROVIDER to <providerName> in config.yaml
 package goose
 
 import (
@@ -59,6 +59,8 @@ func (a *Adapter) Detect() bool {
 // Render produces the FileSet that applies the canonical bundle to goose.
 // config.yaml is MERGED; only GOOSE_PROVIDER, GOOSE_MODEL, and the
 // managed extension entries are overlaid.
+// When Gateway.URL is set, a custom_providers/<providerName>.json file is
+// also added to the FileSet so goose can load the provider on first run.
 func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 	fs := adapter.NewFileSet()
 	cfgPath := filepath.Join(a.home, ".config", "goose", "config.yaml")
@@ -67,9 +69,17 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 
 	provider, model := splitProviderModel(b.Profile.Gateway.DefaultModel)
 	if b.Profile.Gateway.URL != "" {
-		// Custom gateway: signal with provider name. User must create
-		// ~/.config/goose/custom_providers/harness-sync.yaml manually.
-		provider = "harness-sync"
+		// Emit the custom provider JSON file.
+		body, providerName := common.GooseCustomProviderFile(&b.Profile)
+		if body != nil {
+			cpDir := filepath.Join(a.home, ".config", "goose", "custom_providers")
+			fs.Add(adapter.File{
+				Dest:    filepath.Join(cpDir, providerName+".json"),
+				Kind:    adapter.RenderedFile,
+				Content: body,
+			})
+			provider = providerName
+		}
 	}
 
 	overlay := map[string]any{
diff --git a/internal/adapters/goose/goose_test.go b/internal/adapters/goose/goose_test.go
index e901d0e..a633b68 100644
--- a/internal/adapters/goose/goose_test.go
+++ b/internal/adapters/goose/goose_test.go
@@ -1,6 +1,7 @@
 package goose
 
 import (
+	"encoding/json"
 	"os"
 	"path/filepath"
 	"testing"
@@ -89,8 +90,40 @@ func TestGooseRenderGatewayURL(t *testing.T) {
 	cfgDest := filepath.Join(home, ".config", "goose", "config.yaml")
 	var parsed map[string]any
 	require.NoError(t, yaml.Unmarshal(seen[cfgDest].Content, &parsed))
-	// Custom gateway → provider is "harness-sync" (user must write custom_providers file).
-	assert.Equal(t, "harness-sync", parsed["GOOSE_PROVIDER"])
+	// Custom gateway → GOOSE_PROVIDER is the custom provider name.
+	assert.Equal(t, "custom_harness-sync-gateway", parsed["GOOSE_PROVIDER"])
+}
+
+func TestGooseRenderProducesCustomProviderFile(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Profile: canonical.Profile{
+			Gateway: canonical.Gateway{URL: "https://gw", Token: "tok", DefaultModel: "sonnet"},
+			Models:  []canonical.Model{{ID: "claude-sonnet-4-6"}},
+		},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	cpDest := filepath.Join(home, ".config", "goose", "custom_providers", "custom_harness-sync-gateway.json")
+	require.Contains(t, seen, cpDest)
+	assert.Equal(t, adapter.RenderedFile, seen[cpDest].Kind)
+
+	var cp map[string]any
+	require.NoError(t, json.Unmarshal(seen[cpDest].Content, &cp))
+	assert.Equal(t, "custom_harness-sync-gateway", cp["name"])
+	assert.Equal(t, "openai", cp["engine"])
+	assert.Equal(t, true, cp["requires_auth"])
+	assert.Equal(t, "CUSTOM_HARNESS_SYNC_GATEWAY_API_KEY", cp["api_key_env"])
+	models, ok := cp["models"].([]any)
+	require.True(t, ok)
+	require.Len(t, models, 1)
+	m0 := models[0].(map[string]any)
+	assert.Equal(t, "claude-sonnet-4-6", m0["name"])
 }
 
 func TestGooseImport(t *testing.T) {
diff --git a/internal/adapters/kilo/kilo.go b/internal/adapters/kilo/kilo.go
index 65fd311..9496a81 100644
--- a/internal/adapters/kilo/kilo.go
+++ b/internal/adapters/kilo/kilo.go
@@ -66,8 +66,14 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 
 	cfgPath := filepath.Join(base, "kilo.json")
 	existing, _ := os.ReadFile(cfgPath)
-	overlay := map[string]any{
-		"model": b.Profile.Gateway.DefaultModel,
+	modelStr := common.KiloModelString(&b.Profile)
+	overlay := map[string]any{}
+	if providers := common.ProvidersAsMap(&b.Profile); len(providers) > 0 {
+		overlay["provider"] = providers
+	}
+	if modelStr != "" {
+		overlay["model"] = modelStr
+		overlay["small_model"] = modelStr
 	}
 	if mcp := common.BuildMCPMapStyled(&b.MCP, common.MCPOpencodeStyle); len(mcp) > 0 {
 		overlay["mcp"] = mcp
diff --git a/internal/adapters/kilo/kilo_test.go b/internal/adapters/kilo/kilo_test.go
index b304b58..ba59d72 100644
--- a/internal/adapters/kilo/kilo_test.go
+++ b/internal/adapters/kilo/kilo_test.go
@@ -42,12 +42,18 @@ func TestKiloRender(t *testing.T) {
 
 	var parsed map[string]any
 	require.NoError(t, json.Unmarshal(seen[cfgDest].Content, &parsed))
-	assert.Equal(t, "sonnet", parsed["model"])
+	// model is "providerID/modelID" string.
+	assert.Equal(t, "harness-sync-gateway/sonnet", parsed["model"])
+	assert.Equal(t, "harness-sync-gateway/sonnet", parsed["small_model"])
+	// provider map present with npm field.
+	provider, ok := parsed["provider"].(map[string]any)
+	require.True(t, ok, "provider must be a map")
+	gw, ok := provider["harness-sync-gateway"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "@ai-sdk/openai-compatible", gw["npm"])
 	assert.Contains(t, parsed, "mcp")
 	assert.NotContains(t, parsed, "default_model")
 	assert.NotContains(t, parsed, "mcpServers")
-	// kilo has no "providers" concept.
-	assert.NotContains(t, parsed, "providers")
 	// MCP entries use local/remote type (MCPOpencodeStyle).
 	mcp := parsed["mcp"].(map[string]any)
 	fp := mcp["filepuff"].(map[string]any)
@@ -85,11 +91,43 @@ func TestKiloRenderMergesExistingKeys(t *testing.T) {
 	require.NoError(t, json.Unmarshal(seen[cfgDest].Content, &parsed))
 	// User keys preserved.
 	assert.Equal(t, "https://kilo.schema/v1", parsed["$schema"])
-	assert.Equal(t, "claude-haiku", parsed["small_model"])
 	assert.Contains(t, parsed, "compaction")
-	// Model updated.
-	assert.Equal(t, "sonnet", parsed["model"])
+	// Model updated to providerID/modelID; small_model also set.
+	assert.Equal(t, "harness-sync-gateway/sonnet", parsed["model"])
+	assert.Equal(t, "harness-sync-gateway/sonnet", parsed["small_model"])
 }
+func TestKiloRenderEmitsModelString(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Profile: canonical.Profile{
+			Gateway: canonical.Gateway{URL: "https://gw", Token: "tok", DefaultModel: "claude-sonnet-4-6"},
+		},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	cfgDest := filepath.Join(home, ".config", "kilo", "kilo.json")
+	var parsed map[string]any
+	require.NoError(t, json.Unmarshal(seen[cfgDest].Content, &parsed))
+
+	// model must be "harness-sync-gateway/<modelID>".
+	assert.Equal(t, "harness-sync-gateway/claude-sonnet-4-6", parsed["model"])
+	assert.Equal(t, "harness-sync-gateway/claude-sonnet-4-6", parsed["small_model"])
+
+	// provider map has npm field.
+	provider, ok := parsed["provider"].(map[string]any)
+	require.True(t, ok)
+	gw, ok := provider["harness-sync-gateway"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "@ai-sdk/openai-compatible", gw["npm"])
+	opts, ok := gw["options"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "https://gw", opts["baseURL"])
+}
+
 func TestKiloImport(t *testing.T) {
 	home := t.TempDir()
 	base := filepath.Join(home, ".config", "kilo")
diff --git a/internal/adapters/opencode/opencode.go b/internal/adapters/opencode/opencode.go
index 2fbb614..29e0f1e 100644
--- a/internal/adapters/opencode/opencode.go
+++ b/internal/adapters/opencode/opencode.go
@@ -59,7 +59,7 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 	existing, _ := os.ReadFile(cfgPath)
 	overlay := map[string]any{
 		"provider": common.ProvidersAsMap(&b.Profile),
-		"model":    b.Profile.Gateway.DefaultModel,
+		"model":    common.KiloModelString(&b.Profile),
 	}
 	if mcp := common.BuildMCPMapStyled(&b.MCP, common.MCPOpencodeStyle); len(mcp) > 0 {
 		overlay["mcp"] = mcp
diff --git a/internal/adapters/opencode/opencode_test.go b/internal/adapters/opencode/opencode_test.go
index ec862bf..71be998 100644
--- a/internal/adapters/opencode/opencode_test.go
+++ b/internal/adapters/opencode/opencode_test.go
@@ -109,6 +109,37 @@ func TestOpencodeRenderMergesExistingKeys(t *testing.T) {
 	assert.Contains(t, parsed, "model")
 	assert.Contains(t, parsed, "provider")
 }
+func TestOpencodeRenderProviderHasNpm(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Profile: canonical.Profile{
+			Gateway: canonical.Gateway{URL: "https://gw", Token: "tok", DefaultModel: "claude-sonnet-4-6"},
+		},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	cfgDest := filepath.Join(home, ".config", "opencode", "opencode.jsonc")
+	var parsed map[string]any
+	require.NoError(t, json.Unmarshal(seen[cfgDest].Content, &parsed))
+
+	// provider map has npm field.
+	provider, ok := parsed["provider"].(map[string]any)
+	require.True(t, ok)
+	gw, ok := provider["harness-sync-gateway"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "@ai-sdk/openai-compatible", gw["npm"])
+	opts, ok := gw["options"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "https://gw", opts["baseURL"])
+
+	// model is "harness-sync-gateway/modelID".
+	assert.Equal(t, "harness-sync-gateway/claude-sonnet-4-6", parsed["model"])
+}
+
 func TestOpencodeImportStripsComments(t *testing.T) {
 	home := t.TempDir()
 	base := filepath.Join(home, ".config", "opencode")
diff --git a/internal/adapters/zed/zed.go b/internal/adapters/zed/zed.go
index ffc1700..3da2c2a 100644
--- a/internal/adapters/zed/zed.go
+++ b/internal/adapters/zed/zed.go
@@ -74,6 +74,10 @@ func (a *Adapter) Render(b *canonical.Bundle) (*adapter.FileSet, error) {
 		}
 	}
 
+	if lm := common.ZedLanguageModels(&b.Profile); len(lm) > 0 {
+		overlay["language_models"] = lm
+	}
+
 	merged, err := common.MergeJSONKeys(existing, overlay)
 	if err != nil {
 		return nil, err
diff --git a/internal/adapters/zed/zed_test.go b/internal/adapters/zed/zed_test.go
index 25f52c8..c495417 100644
--- a/internal/adapters/zed/zed_test.go
+++ b/internal/adapters/zed/zed_test.go
@@ -111,6 +111,37 @@ func TestZedRenderNoMCP(t *testing.T) {
 	assert.Empty(t, cs)
 }
 
+func TestZedRenderEmitsLanguageModelsOpenAI(t *testing.T) {
+	home := t.TempDir()
+	ad := New(WithHome(home))
+	b := &canonical.Bundle{
+		Profile: canonical.Profile{
+			Gateway: canonical.Gateway{URL: "https://gw", Token: "tok", DefaultModel: "claude-sonnet-4-6"},
+			Models:  []canonical.Model{{ID: "claude-sonnet-4-6", Alias: "sonnet"}},
+		},
+	}
+	fs, err := ad.Render(b)
+	require.NoError(t, err)
+	seen := map[string]adapter.File{}
+	fs.ForEach(func(f adapter.File) { seen[f.Dest] = f })
+
+	cfgDest := filepath.Join(home, ".config", "zed", "settings.json")
+	var parsed map[string]any
+	require.NoError(t, json.Unmarshal(seen[cfgDest].Content, &parsed))
+
+	lm, ok := parsed["language_models"].(map[string]any)
+	require.True(t, ok, "language_models must be present")
+	oai, ok := lm["openai"].(map[string]any)
+	require.True(t, ok, "language_models.openai must be present")
+	assert.Equal(t, "https://gw", oai["api_url"])
+	avail, ok := oai["available_models"].([]any)
+	require.True(t, ok)
+	require.Len(t, avail, 1)
+	m0 := avail[0].(map[string]any)
+	assert.Equal(t, "claude-sonnet-4-6", m0["name"])
+	assert.Equal(t, "sonnet", m0["display_name"])
+}
+
 func TestZedImport(t *testing.T) {
 	home := t.TempDir()
 	base := filepath.Join(home, ".config", "zed")