Use ConfigKit mapping values directly

backends.go

@@ -78,7 +78,8 @@ type AuthenticationProbeConfig struct {
 // It encodes fields without validating them; NewEngine validates the final
 // effective configuration after all selected source layers are combined.
 // Mapping captures a copy of supported input values at creation; unsupported
-// values fail when the source is loaded.
+// values fail when the source is loaded. ExtraParams must use ConfigKit Mapping
+// input forms; callers must explicitly convert numbers or containers as needed.
 func BackendSource(label string, backends []BackendConfig) configkit.Source {
 	definitions := make([]any, 0, len(backends))
 	for _, config := range backends {
@@ -96,7 +97,7 @@ func BackendSource(label string, backends []BackendConfig) configkit.Source {
 			fields["queue_capacity"] = *config.QueueCapacity
 		}
 		if config.ExtraParams != nil {
-			fields["extra_params"] = providerMapForMapping(config.ExtraParams)
+			fields["extra_params"] = config.ExtraParams
 		}
 		if config.SmokeTests != nil {
 			smokeTests := make(map[string]any)

docs/consumers/pkg-promptkit.md

@@ -178,7 +178,12 @@ input := configkit.Input{Source: document}
 ```
 
 `ProfileSource` and `BackendSource` are smaller typed conveniences when null
-is not needed. Backend and profile definitions are supplied by the caller;
+is not needed. Their provider maps use ConfigKit Mapping input forms: built-in
+scalars, `[]any`, and `map[string]any` recursively. Convert `json.Number` or
+typed containers explicitly to an appropriate supported value, choosing numeric
+precision for your application. Mapping captures supported values immediately;
+unsupported or cyclic values are reported when loaded. Runtime override values
+follow their separate rules. Backend and profile definitions are supplied by the caller;
 there is no registration-only backend namespace.
 
 When configuration or message files change, build and validate a new engine,

docs/roadmap/implementation.md

@@ -93,6 +93,10 @@ source-helper GoDoc and source/construction contract tests.
 capture and deferred upstream diagnostics, not acceptance of `json.Number`,
 typed containers, named scalars, or nested pointers by the removed adapter.
 
+Completion: convenience sources pass provider maps directly to ConfigKit;
+the converter was removed. Focused source and construction tests passed with
+Go 1.27.3, including nested capture and deferred unsupported/cyclic errors.
+
 ## Stage 3: Represent The Owning Error Operation
 
 **Catalog:** 7, first part. **Files:** use-case error/runner/preparation boundaries.

profiles.go

@@ -25,7 +25,8 @@ type ProfileConfig struct {
 // It encodes fields without validating them; NewEngine validates the final
 // effective configuration after all selected source layers are combined.
 // Mapping captures a copy of supported input values at creation; unsupported
-// values fail when the source is loaded.
+// values fail when the source is loaded. ExtraParams must use ConfigKit Mapping
+// input forms; callers must explicitly convert numbers or containers as needed.
 func ProfileSource(label string, profiles []ProfileConfig) configkit.Source {
 	definitions := make([]any, 0, len(profiles))
 	for _, config := range profiles {
@@ -67,7 +68,7 @@ func ProfileSource(label string, profiles []ProfileConfig) configkit.Source {
 			fields["api_key_required"] = *config.APIKeyRequired
 		}
 		if config.ExtraParams != nil {
-			fields["extra_params"] = providerMapForMapping(config.ExtraParams)
+			fields["extra_params"] = config.ExtraParams
 		}
 		definitions = append(definitions, fields)
 	}

provider_values.go

@@ -1,121 +0,0 @@
-package promptkit
-
-import (
-	"encoding/json"
-	"reflect"
-	"strconv"
-)
-
-type providerVisit struct {
-	typ reflect.Type
-	ptr uintptr
-}
-
-type invalidProviderNumber struct{}
-
-// providerMapForMapping converts JSON-shaped Go containers to ConfigKit's
-// built-in mapping containers. Unsupported values remain for Mapping to report
-// as deferred source diagnostics during construction.
-func providerMapForMapping(values map[string]any) map[string]any {
-	if values == nil {
-		return nil
-	}
-	converted := make(map[string]any, len(values))
-	active := make(map[providerVisit]bool)
-	for key, value := range values {
-		converted[key] = providerValueForMapping(reflect.ValueOf(value), active, 0)
-	}
-	return converted
-}
-
-func providerValueForMapping(value reflect.Value, active map[providerVisit]bool, depth int) any {
-	if !value.IsValid() {
-		return nil
-	}
-	if depth > 100 {
-		return value.Interface()
-	}
-	for value.Kind() == reflect.Interface || value.Kind() == reflect.Pointer {
-		if value.IsNil() {
-			return nil
-		}
-		if value.Kind() == reflect.Pointer {
-			visit := providerVisit{typ: value.Type(), ptr: value.Pointer()}
-			if active[visit] {
-				return value.Interface()
-			}
-			active[visit] = true
-			defer delete(active, visit)
-		}
-		value = value.Elem()
-	}
-	if value.CanInterface() {
-		if number, ok := value.Interface().(json.Number); ok {
-			if _, err := json.Marshal(number); err != nil {
-				return invalidProviderNumber{}
-			}
-			if integer, err := strconv.ParseInt(string(number), 10, 64); err == nil {
-				return integer
-			}
-			if integer, err := strconv.ParseUint(string(number), 10, 64); err == nil {
-				return integer
-			}
-			if decimal, err := strconv.ParseFloat(string(number), 64); err == nil {
-				return decimal
-			}
-			return number
-		}
-	}
-	switch value.Kind() {
-	case reflect.Map:
-		if value.IsNil() {
-			return nil
-		}
-		if value.Type().Key().Kind() != reflect.String {
-			return value.Interface()
-		}
-		visit := providerVisit{typ: value.Type(), ptr: value.Pointer()}
-		if active[visit] {
-			return value.Interface()
-		}
-		active[visit] = true
-		defer delete(active, visit)
-		converted := make(map[string]any, value.Len())
-		iter := value.MapRange()
-		for iter.Next() {
-			converted[iter.Key().String()] = providerValueForMapping(iter.Value(), active, depth+1)
-		}
-		return converted
-	case reflect.Slice, reflect.Array:
-		if value.Kind() == reflect.Slice {
-			if value.IsNil() {
-				return nil
-			}
-			visit := providerVisit{typ: value.Type(), ptr: value.Pointer()}
-			if visit.ptr != 0 {
-				if active[visit] {
-					return value.Interface()
-				}
-				active[visit] = true
-				defer delete(active, visit)
-			}
-		}
-		converted := make([]any, value.Len())
-		for index := range converted {
-			converted[index] = providerValueForMapping(value.Index(index), active, depth+1)
-		}
-		return converted
-	case reflect.String:
-		return value.String()
-	case reflect.Bool:
-		return value.Bool()
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		return value.Int()
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
-		return value.Uint()
-	case reflect.Float32, reflect.Float64:
-		return value.Float()
-	default:
-		return value.Interface()
-	}
-}

sources_contract_test.go

@@ -3,6 +3,7 @@ package promptkit_test
 import (
 	"bytes"
 	"context"
+	"encoding/json"
 	"errors"
 	"strings"
 	"testing"
@@ -73,3 +74,51 @@ func TestProgrammaticProfileVariantInherits(t *testing.T) {
 		t.Fatalf("inherited profile = %+v, %v", profile, err)
 	}
 }
+
+func TestProgrammaticSourcesCaptureNestedValuesAndDeferInvalidValues(t *testing.T) {
+	endpoint := "https://example.invalid/v1"
+	type namedString string
+	cyclic := map[string]any{}
+	cyclic["self"] = cyclic
+	for _, kind := range []string{"backend", "profile"} {
+		makeSource := func(params map[string]any) configkit.Source {
+			if kind == "backend" {
+				return promptkit.BackendSource("backend", []promptkit.BackendConfig{{ID: "local", Endpoint: &endpoint, ExtraParams: params}})
+			}
+			return promptkit.ProfileSource("profile", []promptkit.ProfileConfig{{ID: "local", ExtraParams: params}})
+		}
+		load := func(source configkit.Source) (*promptkit.Engine, error) {
+			return promptkit.NewEngine(promptkit.Config{Sources: promptkit.ConfigurationSources{Main: &configkit.Input{Source: source}}}, promptkit.WithBundledOpenRouter(false))
+		}
+		t.Run(kind+"/capture", func(t *testing.T) {
+			values := map[string]any{"nested": map[string]any{"items": []any{"original", int64(42), true, nil}}}
+			source := makeSource(values)
+			values["nested"].(map[string]any)["items"].([]any)[0] = "mutated"
+			engine, err := load(source)
+			if err != nil {
+				t.Fatal(err)
+			}
+			view, err := engine.InspectConfiguration()
+			if err != nil {
+				t.Fatal(err)
+			}
+			var output bytes.Buffer
+			if err := view.WriteEffective(&output); err != nil {
+				t.Fatal(err)
+			}
+			if !strings.Contains(output.String(), "original") || strings.Contains(output.String(), "mutated") {
+				t.Fatalf("captured configuration = %s", output.String())
+			}
+		})
+		for name, value := range map[string]any{"number": json.Number("1.25"), "typed slice": []string{"value"}, "named scalar": namedString("value"), "pointer": &endpoint, "cycle": cyclic} {
+			t.Run(kind+"/"+name, func(t *testing.T) {
+				source := makeSource(map[string]any{"value": value})
+				_, err := load(source)
+				var loadErr *configkit.LoadError
+				if !errors.As(err, &loadErr) || len(loadErr.Diagnostics()) == 0 {
+					t.Fatalf("source error = %v", err)
+				}
+			})
+		}
+	}
+}