1package provider
2
3import (
4 "bytes"
5 "context"
6 "encoding/base64"
7 "encoding/json"
8 "fmt"
9 "io"
10 "net/http"
11 "regexp"
12 "strings"
13 "time"
14)
15
16const openaiDefaultBaseURL = "https://api.openai.com"
17
18// versionSegmentSuffix matches a trailing API version segment such as
19// "/v1" or Z.AI's "/v4".
20var versionSegmentSuffix = regexp.MustCompile(`/v\d+$`)
21
22// chatCompletionsURL builds the chat-completions endpoint for an
23// OpenAI-compatible base URL. A base that already carries an API
24// version segment gets "/chat/completions" appended directly; a bare
25// host (e.g. api.openai.com) gets the conventional "/v1/chat/completions".
26//
27// Matching any "/vN" segment (not just "/v1") keeps Z.AI's coding-plan
28// base, which ends in "/paas/v4", from getting a spurious "/v1" that
29// yields ".../paas/v4/v1/chat/completions" and a 404.
30func chatCompletionsURL(baseURL string) string {
31 if versionSegmentSuffix.MatchString(baseURL) {
32 return baseURL + "/chat/completions"
33 }
34 return baseURL + "/v1/chat/completions"
35}
36
37type openaiClient struct {
38 apiKey string
39 baseURL string
40 chatCompletionsPath string
41 name string
42 oauth bool // when true, apiKey actually holds an OAuth access token
43 headers map[string]string
44 http *http.Client
45}
46
47// NewOpenAI creates an OpenAI client using an API key. baseURL may be empty.
48func NewOpenAI(apiKey, baseURL string) Client {
49 if baseURL == "" {
50 baseURL = openaiDefaultBaseURL
51 }
52 return &openaiClient{
53 apiKey: apiKey,
54 baseURL: strings.TrimRight(baseURL, "/"),
55 name: "openai",
56 http: &http.Client{Timeout: 0},
57 }
58}
59
60// NewOpenAIOAuth creates an OpenAI client using a subscription OAuth access token.
61// The token is sent as an HTTP Bearer credential on the standard chat/completions endpoint.
62func NewOpenAIOAuth(accessToken, baseURL string) Client {
63 if baseURL == "" {
64 baseURL = openaiDefaultBaseURL
65 }
66 return &openaiClient{
67 apiKey: accessToken,
68 baseURL: strings.TrimRight(baseURL, "/"),
69 name: "openai",
70 oauth: true,
71 http: &http.Client{Timeout: 0},
72 }
73}
74
75// NewKimi creates a Kimi/Moonshot client. Kimi's chat API is OpenAI-compatible.
76func NewKimi(apiKey, baseURL string) Client {
77 return NewKimiWithHeaders(apiKey, baseURL, nil)
78}
79
80// NewDeepSeek creates a DeepSeek client. DeepSeek's chat API is
81// OpenAI-compatible at https://api.deepseek.com/v1.
82func NewDeepSeek(apiKey, baseURL string) Client {
83 if baseURL == "" {
84 baseURL = "https://api.deepseek.com/v1"
85 }
86 return &openaiClient{
87 apiKey: apiKey,
88 baseURL: strings.TrimRight(baseURL, "/"),
89 name: "deepseek",
90 http: &http.Client{Timeout: 0},
91 }
92}
93
94// NewKimiWithHeaders creates a Kimi/Moonshot client with extra headers.
95// Subscription tokens from Kimi Code need the official CLI's X-Msh-* headers.
96func NewKimiWithHeaders(apiKey, baseURL string, headers map[string]string) Client {
97 if baseURL == "" {
98 baseURL = "https://api.kimi.com/coding/v1"
99 }
100 return &openaiClient{
101 apiKey: apiKey,
102 baseURL: strings.TrimRight(baseURL, "/"),
103 name: "kimi",
104 headers: headers,
105 http: &http.Client{Timeout: 0},
106 }
107}
108
109func (c *openaiClient) Name() string {
110 if c.name != "" {
111 return c.name
112 }
113 return "openai"
114}
115
116// ---- wire types ----
117
118type oaiContentText struct {
119 Type string `json:"type"` // "text"
120 Text string `json:"text"`
121}
122
123type oaiContentImage struct {
124 Type string `json:"type"` // "image_url"
125 ImageURL struct {
126 URL string `json:"url"`
127 } `json:"image_url"`
128}
129
130type oaiToolCallFn struct {
131 Name string `json:"name"`
132 Arguments string `json:"arguments"` // JSON string
133}
134
135type oaiToolCall struct {
136 ID string `json:"id"`
137 Type string `json:"type"` // "function"
138 Function oaiToolCallFn `json:"function"`
139}
140
141type oaiMessage struct {
142 Role string `json:"role"`
143 Content interface{} `json:"content,omitempty"` // string or []block
144 Name string `json:"name,omitempty"`
145 ToolCalls []oaiToolCall `json:"tool_calls,omitempty"`
146 ToolCallID string `json:"tool_call_id,omitempty"`
147 Tools []oaiTool `json:"tools,omitempty"`
148 // ReasoningContent carries the model's chain-of-thought summary
149 // alongside an assistant tool-call message. Required by Kimi's
150 // chat completions endpoint when thinking is enabled and the
151 // assistant message contains a tool call; OpenAI ignores it.
152 ReasoningContent string `json:"reasoning_content,omitempty"`
153}
154
155type oaiTool struct {
156 Type string `json:"type"` // "function"
157 Function struct {
158 Name string `json:"name"`
159 Description string `json:"description,omitempty"`
160 Parameters json.RawMessage `json:"parameters"`
161 } `json:"function"`
162}
163
164type oaiStreamOptions struct {
165 IncludeUsage bool `json:"include_usage"`
166}
167
168type oaiRequest struct {
169 Model string `json:"model"`
170 Messages []oaiMessage `json:"messages"`
171 Tools []oaiTool `json:"tools,omitempty"`
172 ToolChoice string `json:"tool_choice,omitempty"`
173 Stream bool `json:"stream"`
174 StreamOptions *oaiStreamOptions `json:"stream_options,omitempty"`
175 Temperature *float32 `json:"temperature,omitempty"`
176 MaxTokens *int `json:"max_tokens,omitempty"`
177 MaxCompletionTok *int `json:"max_completion_tokens,omitempty"`
178 ReasoningEffort string `json:"reasoning_effort,omitempty"`
179}
180
181// ---- request building ----
182
183func (c *openaiClient) buildRequest(req Request) (*oaiRequest, error) {
184 // The OpenAI wire client is shared by many providers, so prefer its own
185 // provider namespace before falling back to a provider-agnostic lookup.
186 m, err := FindModel(c.Name(), req.Model)
187 if err != nil {
188 m, err = FindModel("", req.Model)
189 }
190 if err != nil {
191 // Unknown model: use sensible defaults so local/custom
192 // models still work without a catalog entry.
193 m = Model{
194 ID: req.Model,
195 ContextWindow: 32768,
196 MaxOutput: 8192,
197 }
198 }
199 reasoning := ClampReasoningForModel(m, req.Reasoning)
200 out := &oaiRequest{
201 Model: req.Model,
202 Stream: true,
203 StreamOptions: &oaiStreamOptions{IncludeUsage: true},
204 Temperature: req.Temperature,
205 }
206
207 maxTok := req.MaxTokens
208 if maxTok <= 0 {
209 maxTok = m.MaxOutput
210 }
211 // Clamp max_tokens so output plus a minimum input reservation fits
212 // within the context window. Some providers (OpenRouter) enforce
213 // input + max_output <= context_length and reject requests where the
214 // total exceeds it. Reserving headroom guarantees the system prompt,
215 // first message, and tool definitions have room.
216 //
217 // The cap is derived from the context window, never from MaxOutput:
218 // MaxOutput is already the output ceiling, so subtracting from it
219 // would shrink every model's budget even when its output comfortably
220 // fits the window. We only lower maxTok when ContextWindow - reserve
221 // is actually tighter than the requested budget, which is exactly the
222 // pathological case (e.g. a model whose MaxOutput equals its window).
223 //
224 // The reserve is proportional (window/8, capped at 4096) rather than a
225 // flat 4096 so small-window models aren't over-penalized: a flat 4096
226 // would halve gpt-4's 8192 budget, while window/8 reserves a sensible
227 // 1024 there and still tops out at 4096 for large contexts.
228 //
229 // Some providers (OpenRouter) report inflated model-level context
230 // windows (e.g. 1000000) while the serving provider enforces a much
231 // tighter limit (e.g. 262144). Discovery already prefers the serving
232 // provider's smaller context_length, so m.ContextWindow is the real
233 // limit by the time we get here.
234 if m.ContextWindow > 0 {
235 reserve := m.ContextWindow / 8
236 const maxReserve = 4096
237 if reserve > maxReserve {
238 reserve = maxReserve
239 }
240 clamped := m.ContextWindow - reserve
241 if clamped < 1 {
242 clamped = 1
243 }
244 if maxTok > clamped {
245 maxTok = clamped
246 }
247 }
248 if m.Reasoning {
249 if maxTok > 0 {
250 out.MaxCompletionTok = &maxTok
251 }
252 effort := OpenAIReasoningEffort(reasoning)
253 if usesAdaptiveThinking(m) {
254 // Some gateways expose adaptive-thinking Anthropic models through
255 // the OpenAI-compatible chat-completions wire. They accept the
256 // same reasoning_effort knob, including the top "xhigh" tier;
257 // don't clamp zot's "maximum" to "high" for those models.
258 effort = OpenAICompatAnthropicEffort(reasoning)
259 }
260 if hasReasoningLevelOverride(m, req.Reasoning) {
261 // Explicit model mappings describe the endpoint's actual effort
262 // values and take precedence over conservative protocol defaults.
263 effort = reasoning
264 }
265 if effort != "" {
266 out.ReasoningEffort = effort
267 }
268 } else if maxTok > 0 {
269 // Omit max_tokens when unknown (some discovered models don't
270 // advertise an output cap) so the server applies its own default
271 // instead of receiving an invalid max_tokens: 0.
272 out.MaxTokens = &maxTok
273 }
274
275 if req.System != "" {
276 out.Messages = append(out.Messages, oaiMessage{Role: "system", Content: req.System})
277 }
278
279 deferredMode := supportsDeferredTools(c.Name()) && isKimiDeferredModel(req.Model)
280 toolByName := make(map[string]Tool, len(req.Tools))
281 for _, t := range req.Tools {
282 toolByName[t.Name] = t
283 }
284 activatedTools := activatedToolNames(req.Messages)
285
286 // DeepSeek's chat-completions API rejects the multimodal content
287 // schema (parts arrays containing image_url). Force every user/tool
288 // message to a plain string and silently drop image blocks for
289 // this provider so historical sessions with screenshots still replay.
290 textOnly := c.name == "deepseek"
291
292 req.Messages = RepairOrphanedToolResults(req.Messages)
293 for _, msg := range req.Messages {
294 switch msg.Role {
295 case RoleUser:
296 content := buildOAIUserContent(msg.Content, textOnly)
297 out.Messages = append(out.Messages, oaiMessage{Role: "user", Content: content})
298 case RoleAssistant:
299 am := oaiMessage{Role: "assistant"}
300 var text strings.Builder
301 var reasoning strings.Builder
302 for _, b := range msg.Content {
303 switch v := b.(type) {
304 case TextBlock:
305 if strings.TrimSpace(v.Text) == "" {
306 continue
307 }
308 if text.Len() > 0 {
309 text.WriteString("\n")
310 }
311 text.WriteString(v.Text)
312 case ToolCallBlock:
313 args := v.Arguments
314 if len(args) == 0 || !json.Valid(args) {
315 args = json.RawMessage("{}")
316 }
317 am.ToolCalls = append(am.ToolCalls, oaiToolCall{
318 ID: v.ID,
319 Type: "function",
320 Function: oaiToolCallFn{
321 Name: v.Name,
322 Arguments: string(args),
323 },
324 })
325 case ReasoningBlock:
326 if v.Summary != "" {
327 if reasoning.Len() > 0 {
328 reasoning.WriteString("\n")
329 }
330 reasoning.WriteString(v.Summary)
331 }
332 }
333 }
334 if text.Len() > 0 {
335 am.Content = text.String()
336 }
337 if reasoning.Len() > 0 && len(am.ToolCalls) > 0 {
338 am.ReasoningContent = reasoning.String()
339 }
340 // Kimi rejects assistant messages with neither visible text nor
341 // tool calls ("assistant must not be empty"). This can happen when
342 // a previous stream produced only reasoning_content, which zot keeps
343 // internally for provider replay but cannot send back as standalone
344 // assistant content on OpenAI-compatible chat-completions APIs.
345 if am.Content == nil && len(am.ToolCalls) == 0 {
346 continue
347 }
348 out.Messages = append(out.Messages, am)
349 case RoleTool:
350 // Each ToolResultBlock becomes its own tool message. Preserve
351 // image blocks for vision-capable OpenAI models instead of
352 // flattening the tool output to plain text.
353 for _, b := range msg.Content {
354 if tr, ok := b.(ToolResultBlock); ok {
355 content := buildOAIToolContent(tr.Content, tr.IsError, textOnly)
356 out.Messages = append(out.Messages, oaiMessage{
357 Role: "tool",
358 ToolCallID: tr.CallID,
359 Content: content,
360 })
361 }
362 }
363 }
364 if deferredMode {
365 var loaded []oaiTool
366 for _, name := range msg.AddedToolNames {
367 if t, ok := toolByName[name]; ok && t.Deferred {
368 loaded = append(loaded, makeOAITool(t))
369 }
370 }
371 if len(loaded) > 0 {
372 out.Messages = append(out.Messages, oaiMessage{Role: "system", Tools: loaded})
373 }
374 }
375 }
376
377 for _, t := range req.Tools {
378 if t.Deferred && (deferredMode || !activatedTools[t.Name]) {
379 continue
380 }
381 out.Tools = append(out.Tools, makeOAITool(t))
382 }
383 if len(out.Tools) > 0 {
384 out.ToolChoice = "auto"
385 }
386
387 return out, nil
388}
389
390func isKimiDeferredModel(model string) bool {
391 model = strings.ToLower(model)
392 return model == "kimi-k3" || strings.HasSuffix(model, "/kimi-k3")
393}
394
395// supportsDeferredTools reports whether a provider speaks Moonshot's
396// deferred-tools handshake, where a tool that becomes available mid-conversation
397// is delivered on a system message carrying a `tools` array.
398//
399// That message is a Moonshot API extension, not OpenAI wire format: it has no
400// content, which a strict chat-completions schema rejects outright. Gondola,
401// which serves kimi-k3 on top of Venice, answers "messages.N: Invalid input"
402// and the conversation cannot recover, because the injection is rebuilt from
403// message history on every later turn. Providers outside this list take the
404// standard path instead, where an activated deferred tool joins the top-level
405// tools array.
406func supportsDeferredTools(provider string) bool {
407 return provider == "moonshotai" || provider == "moonshotai-cn"
408}
409
410func makeOAITool(t Tool) oaiTool {
411 var tool oaiTool
412 tool.Type = "function"
413 tool.Function.Name = t.Name
414 tool.Function.Description = t.Description
415 tool.Function.Parameters = t.Schema
416 return tool
417}
418
419func buildOAIUserContent(blocks []Content, textOnly bool) interface{} {
420 hasImage := false
421 for _, b := range blocks {
422 if _, ok := b.(ImageBlock); ok {
423 hasImage = true
424 break
425 }
426 }
427 if textOnly || !hasImage {
428 var sb strings.Builder
429 for _, b := range blocks {
430 if tb, ok := b.(TextBlock); ok {
431 if sb.Len() > 0 {
432 sb.WriteString("\n")
433 }
434 sb.WriteString(tb.Text)
435 }
436 }
437 return sb.String()
438 }
439 return buildOAIContentBlocks(blocks, false)
440}
441
442func buildOAIToolContent(blocks []Content, isError, textOnly bool) interface{} {
443 hasImage := false
444 for _, b := range blocks {
445 if _, ok := b.(ImageBlock); ok {
446 hasImage = true
447 break
448 }
449 }
450 if textOnly || !hasImage {
451 var sb strings.Builder
452 for _, b := range blocks {
453 if tb, ok := b.(TextBlock); ok {
454 if sb.Len() > 0 {
455 sb.WriteString("\n")
456 }
457 sb.WriteString(tb.Text)
458 }
459 }
460 if isError && sb.Len() > 0 {
461 sb.WriteString(" [error]")
462 }
463 return sb.String()
464 }
465 return buildOAIContentBlocks(blocks, isError)
466}
467
468func buildOAIContentBlocks(blocks []Content, isError bool) []interface{} {
469 var arr []interface{}
470 for _, b := range blocks {
471 switch v := b.(type) {
472 case TextBlock:
473 arr = append(arr, oaiContentText{Type: "text", Text: v.Text})
474 case ImageBlock:
475 var img oaiContentImage
476 img.Type = "image_url"
477 img.ImageURL.URL = "data:" + v.MimeType + ";base64," + base64.StdEncoding.EncodeToString(v.Data)
478 arr = append(arr, img)
479 }
480 }
481 if isError {
482 arr = append(arr, oaiContentText{Type: "text", Text: "[error]"})
483 }
484 return arr
485}
486
487// ---- streaming ----
488
489func (c *openaiClient) chatCompletionsURL() string {
490 if c.chatCompletionsPath != "" {
491 return strings.TrimRight(c.baseURL, "/") + "/" + strings.TrimLeft(c.chatCompletionsPath, "/")
492 }
493 return chatCompletionsURL(c.baseURL)
494}
495
496func (c *openaiClient) Stream(ctx context.Context, req Request) (<-chan Event, error) {
497 endpoint := c.chatCompletionsURL()
498 wire, err := c.buildRequest(req)
499 if err != nil {
500 return nil, err
501 }
502 body, err := json.Marshal(wire)
503 if err != nil {
504 return nil, err
505 }
506 newReq := func() (*http.Request, error) {
507 httpReq, err := http.NewRequestWithContext(ctx, "POST", endpoint, bytes.NewReader(body))
508 if err != nil {
509 return nil, err
510 }
511 httpReq.Header.Set("content-type", "application/json")
512 httpReq.Header.Set("accept", "text/event-stream")
513 httpReq.Header.Set("authorization", "Bearer "+c.apiKey)
514 for k, v := range c.headers {
515 httpReq.Header.Set(k, v)
516 }
517 return httpReq, nil
518 }
519
520 resp, err := doStreamWithRetry(ctx, c.http, newReq)
521 if err != nil {
522 return nil, fmt.Errorf("%s: %w", c.Name(), err)
523 }
524 if resp.StatusCode != http.StatusOK {
525 b, _ := io.ReadAll(resp.Body)
526 resp.Body.Close()
527 return nil, fmt.Errorf("%s: http %d: %s", c.Name(), resp.StatusCode, strings.TrimSpace(string(b)))
528 }
529
530 out := make(chan Event, 16)
531 go c.runStream(ctx, resp, req, out)
532 return out, nil
533}
534
535func (c *openaiClient) runStream(ctx context.Context, resp *http.Response, req Request, out chan<- Event) {
536 defer close(out)
537 defer resp.Body.Close()
538
539 model, _ := FindModel("", req.Model)
540 out <- EventStart{Model: req.Model, Provider: c.Name()}
541
542 raw := make(chan sseEvent, 16)
543 go readSSE(resp.Body, raw)
544
545 // Interleaved block tracking: text and tool_calls preserve their
546 // emission order so the assistant message renders in the same order
547 // the model produced it. The builder fires one kind of block at a
548 // time — incoming text deltas after a tool_call split into a fresh
549 // text block; subsequent tool_calls each get their own slot.
550 type blockEntry struct {
551 kind string // "text" | "tool_use"
552 textBuf strings.Builder
553 toolID string
554 toolName string
555 toolArgs strings.Builder
556 announced bool
557 }
558 var (
559 blocks []*blockEntry
560 currentText *blockEntry // most-recent text block, nil if none
561 toolByIdx = map[int]*blockEntry{} // openai tool_call index -> block
562 reasoningBuf strings.Builder
563 usage Usage
564 stop StopReason = StopEnd
565 finalErr error
566 )
567
568 appendText := func(delta string) {
569 if currentText == nil {
570 currentText = &blockEntry{kind: "text"}
571 blocks = append(blocks, currentText)
572 }
573 currentText.textBuf.WriteString(delta)
574 }
575
576 getOrCreateTool := func(idx int) *blockEntry {
577 if t, ok := toolByIdx[idx]; ok {
578 return t
579 }
580 t := &blockEntry{kind: "tool_use"}
581 toolByIdx[idx] = t
582 blocks = append(blocks, t)
583 // A new tool block breaks the current text block. Subsequent text
584 // deltas will start a fresh text block after this tool.
585 currentText = nil
586 return t
587 }
588
589 assembleMsg := func() Message {
590 content := []Content{}
591 for _, b := range blocks {
592 switch b.kind {
593 case "text":
594 if b.textBuf.Len() > 0 {
595 content = append(content, TextBlock{Text: b.textBuf.String()})
596 }
597 case "tool_use":
598 args := b.toolArgs.String()
599 if args == "" || !json.Valid([]byte(args)) {
600 args = "{}"
601 }
602 content = append(content, ToolCallBlock{
603 ID: b.toolID, Name: b.toolName, Arguments: json.RawMessage(args),
604 })
605 }
606 }
607 if reasoningBuf.Len() > 0 {
608 content = append(content, ReasoningBlock{Summary: reasoningBuf.String()})
609 }
610 return Message{Role: RoleAssistant, Content: content, Time: time.Now()}
611 }
612
613 sendDone := func() {
614 usage.CostUSD = ComputeCost(model, usage)
615 out <- EventUsage{Usage: usage}
616 out <- EventDone{Stop: stop, Err: finalErr, Message: assembleMsg()}
617 }
618
619 for {
620 select {
621 case <-ctx.Done():
622 stop = StopAborted
623 finalErr = ctx.Err()
624 sendDone()
625 return
626 case ev, ok := <-raw:
627 if !ok {
628 sendDone()
629 return
630 }
631 if ev.Data == "[DONE]" {
632 sendDone()
633 return
634 }
635 var chunk struct {
636 Choices []struct {
637 Index int `json:"index"`
638 Delta struct {
639 Content string `json:"content"`
640 ReasoningContent string `json:"reasoning_content"`
641 ToolCalls []struct {
642 Index int `json:"index"`
643 ID string `json:"id"`
644 Type string `json:"type"`
645 Function struct {
646 Name string `json:"name"`
647 Arguments string `json:"arguments"`
648 } `json:"function"`
649 } `json:"tool_calls"`
650 } `json:"delta"`
651 FinishReason string `json:"finish_reason"`
652 } `json:"choices"`
653 Usage *struct {
654 PromptTokens int `json:"prompt_tokens"`
655 CompletionTokens int `json:"completion_tokens"`
656 PromptTokensDetails struct {
657 CachedTokens int `json:"cached_tokens"`
658 } `json:"prompt_tokens_details"`
659 CompletionTokensDetails *struct {
660 ReasoningTokens int `json:"reasoning_tokens"`
661 } `json:"completion_tokens_details"`
662 } `json:"usage"`
663 Error *struct {
664 Message string `json:"message"`
665 Type string `json:"type"`
666 } `json:"error"`
667 }
668 if err := json.Unmarshal([]byte(ev.Data), &chunk); err != nil {
669 continue
670 }
671 if chunk.Error != nil {
672 stop = StopError
673 finalErr = fmt.Errorf("openai: %s", chunk.Error.Message)
674 sendDone()
675 return
676 }
677 if chunk.Usage != nil {
678 usage.InputTokens = chunk.Usage.PromptTokens - chunk.Usage.PromptTokensDetails.CachedTokens
679 if usage.InputTokens < 0 {
680 usage.InputTokens = chunk.Usage.PromptTokens
681 }
682 usage.OutputTokens = chunk.Usage.CompletionTokens
683 usage.CacheReadTokens = chunk.Usage.PromptTokensDetails.CachedTokens
684 if details := chunk.Usage.CompletionTokensDetails; details != nil {
685 usage.ReasoningTokens = details.ReasoningTokens
686 usage.ReasoningTokensKnown = true
687 }
688 }
689 for _, ch := range chunk.Choices {
690 if ch.Delta.ReasoningContent != "" {
691 reasoningBuf.WriteString(ch.Delta.ReasoningContent)
692 }
693 if ch.Delta.Content != "" {
694 appendText(ch.Delta.Content)
695 out <- EventTextDelta{Delta: ch.Delta.Content}
696 }
697 for _, tc := range ch.Delta.ToolCalls {
698 t := getOrCreateTool(tc.Index)
699 if tc.ID != "" {
700 t.toolID = tc.ID
701 }
702 if tc.Function.Name != "" {
703 t.toolName = tc.Function.Name
704 }
705 if !t.announced && t.toolID != "" && t.toolName != "" {
706 t.announced = true
707 out <- EventToolStart{ID: t.toolID, Name: t.toolName}
708 }
709 if tc.Function.Arguments != "" {
710 t.toolArgs.WriteString(tc.Function.Arguments)
711 if t.announced {
712 out <- EventToolArgs{ID: t.toolID, Delta: tc.Function.Arguments}
713 }
714 }
715 }
716 switch ch.FinishReason {
717 case "stop":
718 stop = StopEnd
719 case "length":
720 stop = StopLength
721 case "tool_calls", "function_call":
722 stop = StopToolUse
723 for _, b := range blocks {
724 if b.kind == "tool_use" && b.announced {
725 out <- EventToolEnd{ID: b.toolID}
726 }
727 }
728 }
729 }
730 }
731 }
732}