feat: version ai result schemas

README.md

@@ -43,7 +43,8 @@ Input can be either explicit messages:
 ```
 
 or compact `system` / `user` fields. The completed job result contains
-`content`, `model`, `usage` and `duration_ms`.
+`schema_version=ai.chat_result.v1`, `content`, `model`, `usage` and
+`duration_ms`.
 
 `call_analysis` and `transcript_summary` use the same input contract as
 `llm_chat`; callers may include domain metadata fields in `input`, but the
@@ -55,6 +56,9 @@ worker only reads chat fields such as `system`, `user`, `messages`,
 `/v1/audio/transcriptions` endpoint. The returned `segments` field stays
 compatible with telephony. If the provider returns one long segment, AI Service
 splits it into smaller transcript segments without inventing speaker labels.
+The completed job result contains
+`schema_version=ai.transcription_result.v1`, `provider`, `model`, `language`,
+`segments`, optional provider `attempts` and `duration_ms`.
 
 AI-server compose snippet for Whisper Large v3 lives in
 `deploy/ai-server/docker-compose.audio.yml`:
@@ -110,6 +114,20 @@ explicitly retryable categories while attempts remain.
 Domain services may still expose manual retry for terminal errors after the
 underlying data or prompt is corrected.
 
+## Result schemas
+
+AI Service result payloads are versioned with `schema_version`. Consumers should
+ignore unknown fields and reject only unsupported major schema names.
+
+Current schemas:
+
+- `ai.chat_result.v1`: `{schema_version, content, model, usage?, duration_ms}`.
+- `ai.transcription_result.v1`:
+  `{schema_version, provider?, model?, attempts?, language, segments, duration_ms}`.
+
+New optional fields may be added to a `v1` schema without a breaking change.
+Breaking shape changes require a new schema name.
+
 ## Configuration
 
 - `HTTP_HOST`, default `0.0.0.0`

internal/llm/client.go

@@ -38,7 +38,10 @@ type Usage struct {
 	TotalTokens      int `json:"total_tokens"`
 }
 
+const ChatResultSchemaVersion = "ai.chat_result.v1"
+
 type ChatResult struct {
+	SchemaVersion string `json:"schema_version"`
 	Content       string `json:"content"`
 	Model         string `json:"model"`
 	Usage         *Usage `json:"usage,omitempty"`
@@ -137,6 +140,7 @@ func (c *Client) Chat(ctx context.Context, in ChatInput) (*ChatResult, error) {
 		modelName = c.model
 	}
 	return &ChatResult{
+		SchemaVersion: ChatResultSchemaVersion,
 		Content:       out.Choices[0].Message.Content,
 		Model:         modelName,
 		Usage:         out.Usage,

internal/llm/client_test.go

@@ -0,0 +1,43 @@
+package llm
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestChatResultIncludesSchemaVersion(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/v1/chat/completions" {
+			t.Fatalf("path = %q, want /v1/chat/completions", r.URL.Path)
+		}
+		_ = json.NewEncoder(w).Encode(map[string]any{
+			"model": "qwen2.5-14b",
+			"choices": []map[string]any{
+				{"message": map[string]string{"role": "assistant", "content": `{"ok":true}`}},
+			},
+			"usage": map[string]int{
+				"prompt_tokens":     10,
+				"completion_tokens": 2,
+				"total_tokens":      12,
+			},
+		})
+	}))
+	defer server.Close()
+
+	client := New(server.URL, "", "fallback-model", 0)
+	got, err := client.Chat(t.Context(), ChatInput{User: "test", MaxTokens: 32})
+	if err != nil {
+		t.Fatalf("Chat: %v", err)
+	}
+	if got.SchemaVersion != ChatResultSchemaVersion {
+		t.Fatalf("schema_version = %q, want %q", got.SchemaVersion, ChatResultSchemaVersion)
+	}
+	if got.Content != `{"ok":true}` {
+		t.Fatalf("content = %q", got.Content)
+	}
+	if got.Usage == nil || got.Usage.TotalTokens != 12 {
+		t.Fatalf("usage = %#v", got.Usage)
+	}
+}

internal/transcription/client.go

@@ -60,7 +60,10 @@ type Segment struct {
 	Speaker string  `json:"speaker,omitempty"`
 }
 
+const ResultSchemaVersion = "ai.transcription_result.v1"
+
 type Result struct {
+	SchemaVersion string    `json:"schema_version"`
 	Provider      string    `json:"provider,omitempty"`
 	Model         string    `json:"model,omitempty"`
 	Attempts      []Attempt `json:"attempts,omitempty"`
@@ -199,6 +202,7 @@ func (c *Client) transcribeWithProvider(ctx context.Context, provider ProviderCo
 	attempt.Text = text
 	attempt.Segments = segments
 	return &Result{
+		SchemaVersion: ResultSchemaVersion,
 		Provider:      provider.Name,
 		Model:         resp.Model,
 		Language:      firstNonEmpty(resp.Language, in.Language, "unknown"),

internal/transcription/client_test.go

@@ -84,6 +84,9 @@ func TestWhisperUsesAudioTranscriptionsEndpoint(t *testing.T) {
 	if len(got.Segments) != 2 || got.Segments[0].Text != "Алло, тест." || got.Segments[1].Start != 1.2 {
 		t.Fatalf("segments = %#v", got.Segments)
 	}
+	if got.SchemaVersion != ResultSchemaVersion {
+		t.Fatalf("schema_version = %q, want %q", got.SchemaVersion, ResultSchemaVersion)
+	}
 }
 
 func TestWhisperFallsBackToJSONWhenVerboseJSONUnsupported(t *testing.T) {