Allow JSON-compatible extra params

internal/adapter/http/dto.go

@@ -21,16 +21,16 @@ type inputRefDTO struct {
 }
 
 type modelOverrideRequestDTO struct {
-	Endpoint        string            `json:"endpoint,omitempty"`
-	Model           string            `json:"model,omitempty"`
-	Temperature     *float64          `json:"temperature,omitempty"`
-	MaxTokens       *int              `json:"max_tokens,omitempty"`
-	TopP            *float64          `json:"top_p,omitempty"`
-	TimeoutSeconds  *int              `json:"timeout_seconds,omitempty"`
-	ServiceTier     string            `json:"service_tier,omitempty"`
-	ReasoningEffort string            `json:"reasoning_effort,omitempty"`
-	APIKeyEnv       string            `json:"api_key_env,omitempty"`
-	ExtraParams     map[string]string `json:"extra_params,omitempty"`
+	Endpoint        string         `json:"endpoint,omitempty"`
+	Model           string         `json:"model,omitempty"`
+	Temperature     *float64       `json:"temperature,omitempty"`
+	MaxTokens       *int           `json:"max_tokens,omitempty"`
+	TopP            *float64       `json:"top_p,omitempty"`
+	TimeoutSeconds  *int           `json:"timeout_seconds,omitempty"`
+	ServiceTier     string         `json:"service_tier,omitempty"`
+	ReasoningEffort string         `json:"reasoning_effort,omitempty"`
+	APIKeyEnv       string         `json:"api_key_env,omitempty"`
+	ExtraParams     map[string]any `json:"extra_params,omitempty"`
 }
 
 type runResponseDTO struct {

internal/adapter/http/handler.go

@@ -137,7 +137,7 @@ func executionTargetOverrideFromModelOverrideDTO(dto *modelOverrideRequestDTO) *
 		ServiceTier:     dto.ServiceTier,
 		ReasoningEffort: dto.ReasoningEffort,
 		APIKeyEnv:       dto.APIKeyEnv,
-		ExtraParams:     stringMapToAnyMap(dto.ExtraParams),
+		ExtraParams:     dto.ExtraParams,
 	}
 }
 
@@ -156,17 +156,6 @@ func modelParamsDTOFromExecutionTarget(target domain.ExecutionTarget) modelParam
 	}
 }
 
-func stringMapToAnyMap(src map[string]string) map[string]any {
-	if len(src) == 0 {
-		return nil
-	}
-	out := make(map[string]any, len(src))
-	for k, v := range src {
-		out[k] = v
-	}
-	return out
-}
-
 func mapValidation(v domain.ValidationResult) validationDTO {
 	return validationDTO{
 		Status:         string(v.Status),

internal/adapter/http/handler_test.go

@@ -250,6 +250,50 @@ func TestHandlerModelOverrideMapsAllSupportedExecutionFields(t *testing.T) {
 	}
 }
 
+func TestHandlerModelOverrideAcceptsJSONCompatibleExtraParams(t *testing.T) {
+	r := &fakeRunner{result: &domain.RunResult{
+		Artifact:             domain.Artifact{Body: []byte("ok")},
+		Validation:           domain.ValidationResult{Status: domain.ValidationPassed, Mode: domain.ValidationBasic, IsValid: true},
+		EffectiveModelParams: domain.ExecutionTarget{Endpoint: "http://llm/v1", Model: "m1"},
+	}}
+	h := NewHandler(r)
+
+	reqBody := `{
+		"prompt_id": "prompt-1",
+		"inputs": {"transcript": {"type": "file", "uri": "./t.md"}},
+		"model": {
+			"extra_params": {
+				"string_value": "enabled",
+				"number_value": 42,
+				"boolean_value": true,
+				"object_value": {"nested": "value", "count": 2},
+				"array_value": ["first", 3, false]
+			}
+		}
+	}`
+	req := httptest.NewRequest(http.MethodPost, "/v1/runs", bytes.NewBufferString(reqBody))
+	w := httptest.NewRecorder()
+
+	h.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d body=%s", w.Code, w.Body.String())
+	}
+	if r.last.Execution == nil {
+		t.Fatal("expected execution override in run request")
+	}
+	want := map[string]any{
+		"string_value":  "enabled",
+		"number_value":  float64(42),
+		"boolean_value": true,
+		"object_value":  map[string]any{"nested": "value", "count": float64(2)},
+		"array_value":   []any{"first", float64(3), false},
+	}
+	if !reflect.DeepEqual(r.last.Execution.ExtraParams, want) {
+		t.Fatalf("unexpected mapped extra_params:\ngot=%#v\nwant=%#v", r.last.Execution.ExtraParams, want)
+	}
+}
+
 func TestHandlerModelOverrideExplicitZeroTemperatureMapsAsPresent(t *testing.T) {
 	r := &fakeRunner{result: &domain.RunResult{
 		Artifact:             domain.Artifact{Body: []byte("ok")},
@@ -336,6 +380,8 @@ func TestHandlerResponseMetadataModelParamsIncludesAllSupportedFields(t *testing
 			APIKeyEnv:       "SCRIPTORIUM_API_KEY",
 			ExtraParams: map[string]any{
 				"provider_option": "on",
+				"number_value":    42,
+				"object_value":    map[string]any{"nested": "value"},
 			},
 		},
 	}}
@@ -390,6 +436,13 @@ func TestHandlerResponseMetadataModelParamsIncludesAllSupportedFields(t *testing
 	if extraParams["provider_option"] != "on" {
 		t.Fatalf("unexpected extra_params.provider_option: %#v", extraParams["provider_option"])
 	}
+	if extraParams["number_value"] != float64(42) {
+		t.Fatalf("unexpected extra_params.number_value: %#v", extraParams["number_value"])
+	}
+	objectValue, ok := extraParams["object_value"].(map[string]any)
+	if !ok || objectValue["nested"] != "value" {
+		t.Fatalf("unexpected extra_params.object_value: %#v", extraParams["object_value"])
+	}
 }
 
 func TestHandlerInvalidJSON(t *testing.T) {