thread.rs

  1use std::sync::Arc;
  2
  3use anyhow::{Context as _, Result};
  4use assistant_tool::ToolWorkingSet;
  5use chrono::{DateTime, Utc};
  6use collections::{BTreeMap, HashMap, HashSet};
  7use futures::StreamExt as _;
  8use gpui::{App, AppContext, Context, Entity, EventEmitter, SharedString, Task};
  9use language_model::{
 10    LanguageModel, LanguageModelCompletionEvent, LanguageModelRegistry, LanguageModelRequest,
 11    LanguageModelRequestMessage, LanguageModelRequestTool, LanguageModelToolResult,
 12    LanguageModelToolUseId, MaxMonthlySpendReachedError, MessageContent, PaymentRequiredError,
 13    Role, StopReason,
 14};
 15use project::Project;
 16use prompt_store::PromptBuilder;
 17use scripting_tool::{ScriptingSession, ScriptingTool};
 18use serde::{Deserialize, Serialize};
 19use util::{post_inc, ResultExt, TryFutureExt as _};
 20use uuid::Uuid;
 21
 22use crate::context::{attach_context_to_message, ContextId, ContextSnapshot};
 23use crate::thread_store::SavedThread;
 24use crate::tool_use::{PendingToolUse, ToolUse, ToolUseState};
 25
 26#[derive(Debug, Clone, Copy)]
 27pub enum RequestKind {
 28    Chat,
 29    /// Used when summarizing a thread.
 30    Summarize,
 31}
 32
 33#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Serialize, Deserialize)]
 34pub struct ThreadId(Arc<str>);
 35
 36impl ThreadId {
 37    pub fn new() -> Self {
 38        Self(Uuid::new_v4().to_string().into())
 39    }
 40}
 41
 42impl std::fmt::Display for ThreadId {
 43    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 44        write!(f, "{}", self.0)
 45    }
 46}
 47
 48#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Copy, Serialize, Deserialize)]
 49pub struct MessageId(pub(crate) usize);
 50
 51impl MessageId {
 52    fn post_inc(&mut self) -> Self {
 53        Self(post_inc(&mut self.0))
 54    }
 55}
 56
 57/// A message in a [`Thread`].
 58#[derive(Debug, Clone)]
 59pub struct Message {
 60    pub id: MessageId,
 61    pub role: Role,
 62    pub text: String,
 63}
 64
 65/// A thread of conversation with the LLM.
 66pub struct Thread {
 67    id: ThreadId,
 68    updated_at: DateTime<Utc>,
 69    summary: Option<SharedString>,
 70    pending_summary: Task<Option<()>>,
 71    messages: Vec<Message>,
 72    next_message_id: MessageId,
 73    context: BTreeMap<ContextId, ContextSnapshot>,
 74    context_by_message: HashMap<MessageId, Vec<ContextId>>,
 75    completion_count: usize,
 76    pending_completions: Vec<PendingCompletion>,
 77    project: Entity<Project>,
 78    prompt_builder: Arc<PromptBuilder>,
 79    tools: Arc<ToolWorkingSet>,
 80    tool_use: ToolUseState,
 81    scripting_session: Entity<ScriptingSession>,
 82    scripting_tool_use: ToolUseState,
 83}
 84
 85impl Thread {
 86    pub fn new(
 87        project: Entity<Project>,
 88        tools: Arc<ToolWorkingSet>,
 89        prompt_builder: Arc<PromptBuilder>,
 90        cx: &mut Context<Self>,
 91    ) -> Self {
 92        let scripting_session = cx.new(|cx| ScriptingSession::new(project.clone(), cx));
 93
 94        Self {
 95            id: ThreadId::new(),
 96            updated_at: Utc::now(),
 97            summary: None,
 98            pending_summary: Task::ready(None),
 99            messages: Vec::new(),
100            next_message_id: MessageId(0),
101            context: BTreeMap::default(),
102            context_by_message: HashMap::default(),
103            completion_count: 0,
104            pending_completions: Vec::new(),
105            project,
106            prompt_builder,
107            tools,
108            tool_use: ToolUseState::new(),
109            scripting_session,
110            scripting_tool_use: ToolUseState::new(),
111        }
112    }
113
114    pub fn from_saved(
115        id: ThreadId,
116        saved: SavedThread,
117        project: Entity<Project>,
118        tools: Arc<ToolWorkingSet>,
119        prompt_builder: Arc<PromptBuilder>,
120        cx: &mut Context<Self>,
121    ) -> Self {
122        let next_message_id = MessageId(
123            saved
124                .messages
125                .last()
126                .map(|message| message.id.0 + 1)
127                .unwrap_or(0),
128        );
129        let tool_use =
130            ToolUseState::from_saved_messages(&saved.messages, |name| name != ScriptingTool::NAME);
131        let scripting_tool_use =
132            ToolUseState::from_saved_messages(&saved.messages, |name| name == ScriptingTool::NAME);
133        let scripting_session = cx.new(|cx| ScriptingSession::new(project.clone(), cx));
134
135        Self {
136            id,
137            updated_at: saved.updated_at,
138            summary: Some(saved.summary),
139            pending_summary: Task::ready(None),
140            messages: saved
141                .messages
142                .into_iter()
143                .map(|message| Message {
144                    id: message.id,
145                    role: message.role,
146                    text: message.text,
147                })
148                .collect(),
149            next_message_id,
150            context: BTreeMap::default(),
151            context_by_message: HashMap::default(),
152            completion_count: 0,
153            pending_completions: Vec::new(),
154            project,
155            prompt_builder,
156            tools,
157            tool_use,
158            scripting_session,
159            scripting_tool_use,
160        }
161    }
162
163    pub fn id(&self) -> &ThreadId {
164        &self.id
165    }
166
167    pub fn is_empty(&self) -> bool {
168        self.messages.is_empty()
169    }
170
171    pub fn updated_at(&self) -> DateTime<Utc> {
172        self.updated_at
173    }
174
175    pub fn touch_updated_at(&mut self) {
176        self.updated_at = Utc::now();
177    }
178
179    pub fn summary(&self) -> Option<SharedString> {
180        self.summary.clone()
181    }
182
183    pub fn summary_or_default(&self) -> SharedString {
184        const DEFAULT: SharedString = SharedString::new_static("New Thread");
185        self.summary.clone().unwrap_or(DEFAULT)
186    }
187
188    pub fn set_summary(&mut self, summary: impl Into<SharedString>, cx: &mut Context<Self>) {
189        self.summary = Some(summary.into());
190        cx.emit(ThreadEvent::SummaryChanged);
191    }
192
193    pub fn message(&self, id: MessageId) -> Option<&Message> {
194        self.messages.iter().find(|message| message.id == id)
195    }
196
197    pub fn messages(&self) -> impl Iterator<Item = &Message> {
198        self.messages.iter()
199    }
200
201    pub fn is_streaming(&self) -> bool {
202        !self.pending_completions.is_empty()
203    }
204
205    pub fn tools(&self) -> &Arc<ToolWorkingSet> {
206        &self.tools
207    }
208
209    pub fn context_for_message(&self, id: MessageId) -> Option<Vec<ContextSnapshot>> {
210        let context = self.context_by_message.get(&id)?;
211        Some(
212            context
213                .into_iter()
214                .filter_map(|context_id| self.context.get(&context_id))
215                .cloned()
216                .collect::<Vec<_>>(),
217        )
218    }
219
220    /// Returns whether all of the tool uses have finished running.
221    pub fn all_tools_finished(&self) -> bool {
222        let mut all_pending_tool_uses = self
223            .tool_use
224            .pending_tool_uses()
225            .into_iter()
226            .chain(self.scripting_tool_use.pending_tool_uses());
227
228        // If the only pending tool uses left are the ones with errors, then that means that we've finished running all
229        // of the pending tools.
230        all_pending_tool_uses.all(|tool_use| tool_use.status.is_error())
231    }
232
233    pub fn tool_uses_for_message(&self, id: MessageId) -> Vec<ToolUse> {
234        self.tool_use.tool_uses_for_message(id)
235    }
236
237    pub fn scripting_tool_uses_for_message(&self, id: MessageId) -> Vec<ToolUse> {
238        self.scripting_tool_use.tool_uses_for_message(id)
239    }
240
241    pub fn tool_results_for_message(&self, id: MessageId) -> Vec<&LanguageModelToolResult> {
242        self.tool_use.tool_results_for_message(id)
243    }
244
245    pub fn scripting_tool_results_for_message(
246        &self,
247        id: MessageId,
248    ) -> Vec<&LanguageModelToolResult> {
249        self.scripting_tool_use.tool_results_for_message(id)
250    }
251
252    pub fn scripting_changed_buffers<'a>(
253        &self,
254        cx: &'a App,
255    ) -> impl ExactSizeIterator<Item = &'a Entity<language::Buffer>> {
256        self.scripting_session.read(cx).changed_buffers()
257    }
258
259    pub fn message_has_tool_results(&self, message_id: MessageId) -> bool {
260        self.tool_use.message_has_tool_results(message_id)
261    }
262
263    pub fn message_has_scripting_tool_results(&self, message_id: MessageId) -> bool {
264        self.scripting_tool_use.message_has_tool_results(message_id)
265    }
266
267    pub fn insert_user_message(
268        &mut self,
269        text: impl Into<String>,
270        context: Vec<ContextSnapshot>,
271        cx: &mut Context<Self>,
272    ) -> MessageId {
273        let message_id = self.insert_message(Role::User, text, cx);
274        let context_ids = context.iter().map(|context| context.id).collect::<Vec<_>>();
275        self.context
276            .extend(context.into_iter().map(|context| (context.id, context)));
277        self.context_by_message.insert(message_id, context_ids);
278        message_id
279    }
280
281    pub fn insert_message(
282        &mut self,
283        role: Role,
284        text: impl Into<String>,
285        cx: &mut Context<Self>,
286    ) -> MessageId {
287        let id = self.next_message_id.post_inc();
288        self.messages.push(Message {
289            id,
290            role,
291            text: text.into(),
292        });
293        self.touch_updated_at();
294        cx.emit(ThreadEvent::MessageAdded(id));
295        id
296    }
297
298    pub fn edit_message(
299        &mut self,
300        id: MessageId,
301        new_role: Role,
302        new_text: String,
303        cx: &mut Context<Self>,
304    ) -> bool {
305        let Some(message) = self.messages.iter_mut().find(|message| message.id == id) else {
306            return false;
307        };
308        message.role = new_role;
309        message.text = new_text;
310        self.touch_updated_at();
311        cx.emit(ThreadEvent::MessageEdited(id));
312        true
313    }
314
315    pub fn delete_message(&mut self, id: MessageId, cx: &mut Context<Self>) -> bool {
316        let Some(index) = self.messages.iter().position(|message| message.id == id) else {
317            return false;
318        };
319        self.messages.remove(index);
320        self.context_by_message.remove(&id);
321        self.touch_updated_at();
322        cx.emit(ThreadEvent::MessageDeleted(id));
323        true
324    }
325
326    /// Returns the representation of this [`Thread`] in a textual form.
327    ///
328    /// This is the representation we use when attaching a thread as context to another thread.
329    pub fn text(&self) -> String {
330        let mut text = String::new();
331
332        for message in &self.messages {
333            text.push_str(match message.role {
334                language_model::Role::User => "User:",
335                language_model::Role::Assistant => "Assistant:",
336                language_model::Role::System => "System:",
337            });
338            text.push('\n');
339
340            text.push_str(&message.text);
341            text.push('\n');
342        }
343
344        text
345    }
346
347    pub fn send_to_model(
348        &mut self,
349        model: Arc<dyn LanguageModel>,
350        request_kind: RequestKind,
351        cx: &mut Context<Self>,
352    ) {
353        let mut request = self.to_completion_request(request_kind, cx);
354        request.tools = {
355            let mut tools = Vec::new();
356
357            if self.tools.is_scripting_tool_enabled() {
358                tools.push(LanguageModelRequestTool {
359                    name: ScriptingTool::NAME.into(),
360                    description: ScriptingTool::DESCRIPTION.into(),
361                    input_schema: ScriptingTool::input_schema(),
362                });
363            }
364
365            tools.extend(self.tools().enabled_tools(cx).into_iter().map(|tool| {
366                LanguageModelRequestTool {
367                    name: tool.name(),
368                    description: tool.description(),
369                    input_schema: tool.input_schema(),
370                }
371            }));
372
373            tools
374        };
375
376        self.stream_completion(request, model, cx);
377    }
378
379    pub fn to_completion_request(
380        &self,
381        request_kind: RequestKind,
382        cx: &App,
383    ) -> LanguageModelRequest {
384        let worktree_root_names = self
385            .project
386            .read(cx)
387            .worktree_root_names(cx)
388            .map(ToString::to_string)
389            .collect::<Vec<_>>();
390        let system_prompt = self
391            .prompt_builder
392            .generate_assistant_system_prompt(worktree_root_names)
393            .context("failed to generate assistant system prompt")
394            .log_err()
395            .unwrap_or_default();
396
397        let mut request = LanguageModelRequest {
398            messages: vec![LanguageModelRequestMessage {
399                role: Role::System,
400                content: vec![MessageContent::Text(system_prompt)],
401                cache: true,
402            }],
403            tools: Vec::new(),
404            stop: Vec::new(),
405            temperature: None,
406        };
407
408        let mut referenced_context_ids = HashSet::default();
409
410        for message in &self.messages {
411            if let Some(context_ids) = self.context_by_message.get(&message.id) {
412                referenced_context_ids.extend(context_ids);
413            }
414
415            let mut request_message = LanguageModelRequestMessage {
416                role: message.role,
417                content: Vec::new(),
418                cache: false,
419            };
420
421            match request_kind {
422                RequestKind::Chat => {
423                    self.tool_use
424                        .attach_tool_results(message.id, &mut request_message);
425                    self.scripting_tool_use
426                        .attach_tool_results(message.id, &mut request_message);
427                }
428                RequestKind::Summarize => {
429                    // We don't care about tool use during summarization.
430                }
431            }
432
433            if !message.text.is_empty() {
434                request_message
435                    .content
436                    .push(MessageContent::Text(message.text.clone()));
437            }
438
439            match request_kind {
440                RequestKind::Chat => {
441                    self.tool_use
442                        .attach_tool_uses(message.id, &mut request_message);
443                    self.scripting_tool_use
444                        .attach_tool_uses(message.id, &mut request_message);
445                }
446                RequestKind::Summarize => {
447                    // We don't care about tool use during summarization.
448                }
449            };
450
451            request.messages.push(request_message);
452        }
453
454        if !referenced_context_ids.is_empty() {
455            let mut context_message = LanguageModelRequestMessage {
456                role: Role::User,
457                content: Vec::new(),
458                cache: false,
459            };
460
461            let referenced_context = referenced_context_ids
462                .into_iter()
463                .filter_map(|context_id| self.context.get(context_id))
464                .cloned();
465            attach_context_to_message(&mut context_message, referenced_context);
466
467            request.messages.push(context_message);
468        }
469
470        request
471    }
472
473    pub fn stream_completion(
474        &mut self,
475        request: LanguageModelRequest,
476        model: Arc<dyn LanguageModel>,
477        cx: &mut Context<Self>,
478    ) {
479        let pending_completion_id = post_inc(&mut self.completion_count);
480
481        let task = cx.spawn(|thread, mut cx| async move {
482            let stream = model.stream_completion(request, &cx);
483            let stream_completion = async {
484                let mut events = stream.await?;
485                let mut stop_reason = StopReason::EndTurn;
486
487                while let Some(event) = events.next().await {
488                    let event = event?;
489
490                    thread.update(&mut cx, |thread, cx| {
491                        match event {
492                            LanguageModelCompletionEvent::StartMessage { .. } => {
493                                thread.insert_message(Role::Assistant, String::new(), cx);
494                            }
495                            LanguageModelCompletionEvent::Stop(reason) => {
496                                stop_reason = reason;
497                            }
498                            LanguageModelCompletionEvent::Text(chunk) => {
499                                if let Some(last_message) = thread.messages.last_mut() {
500                                    if last_message.role == Role::Assistant {
501                                        last_message.text.push_str(&chunk);
502                                        cx.emit(ThreadEvent::StreamedAssistantText(
503                                            last_message.id,
504                                            chunk,
505                                        ));
506                                    } else {
507                                        // If we won't have an Assistant message yet, assume this chunk marks the beginning
508                                        // of a new Assistant response.
509                                        //
510                                        // Importantly: We do *not* want to emit a `StreamedAssistantText` event here, as it
511                                        // will result in duplicating the text of the chunk in the rendered Markdown.
512                                        thread.insert_message(Role::Assistant, chunk, cx);
513                                    };
514                                }
515                            }
516                            LanguageModelCompletionEvent::ToolUse(tool_use) => {
517                                if let Some(last_assistant_message) = thread
518                                    .messages
519                                    .iter()
520                                    .rfind(|message| message.role == Role::Assistant)
521                                {
522                                    if tool_use.name.as_ref() == ScriptingTool::NAME {
523                                        thread
524                                            .scripting_tool_use
525                                            .request_tool_use(last_assistant_message.id, tool_use);
526                                    } else {
527                                        thread
528                                            .tool_use
529                                            .request_tool_use(last_assistant_message.id, tool_use);
530                                    }
531                                }
532                            }
533                        }
534
535                        thread.touch_updated_at();
536                        cx.emit(ThreadEvent::StreamedCompletion);
537                        cx.notify();
538                    })?;
539
540                    smol::future::yield_now().await;
541                }
542
543                thread.update(&mut cx, |thread, cx| {
544                    thread
545                        .pending_completions
546                        .retain(|completion| completion.id != pending_completion_id);
547
548                    if thread.summary.is_none() && thread.messages.len() >= 2 {
549                        thread.summarize(cx);
550                    }
551                })?;
552
553                anyhow::Ok(stop_reason)
554            };
555
556            let result = stream_completion.await;
557
558            thread
559                .update(&mut cx, |thread, cx| match result.as_ref() {
560                    Ok(stop_reason) => match stop_reason {
561                        StopReason::ToolUse => {
562                            cx.emit(ThreadEvent::UsePendingTools);
563                        }
564                        StopReason::EndTurn => {}
565                        StopReason::MaxTokens => {}
566                    },
567                    Err(error) => {
568                        if error.is::<PaymentRequiredError>() {
569                            cx.emit(ThreadEvent::ShowError(ThreadError::PaymentRequired));
570                        } else if error.is::<MaxMonthlySpendReachedError>() {
571                            cx.emit(ThreadEvent::ShowError(ThreadError::MaxMonthlySpendReached));
572                        } else {
573                            let error_message = error
574                                .chain()
575                                .map(|err| err.to_string())
576                                .collect::<Vec<_>>()
577                                .join("\n");
578                            cx.emit(ThreadEvent::ShowError(ThreadError::Message(
579                                SharedString::from(error_message.clone()),
580                            )));
581                        }
582
583                        thread.cancel_last_completion();
584                    }
585                })
586                .ok();
587        });
588
589        self.pending_completions.push(PendingCompletion {
590            id: pending_completion_id,
591            _task: task,
592        });
593    }
594
595    pub fn summarize(&mut self, cx: &mut Context<Self>) {
596        let Some(provider) = LanguageModelRegistry::read_global(cx).active_provider() else {
597            return;
598        };
599        let Some(model) = LanguageModelRegistry::read_global(cx).active_model() else {
600            return;
601        };
602
603        if !provider.is_authenticated(cx) {
604            return;
605        }
606
607        let mut request = self.to_completion_request(RequestKind::Summarize, cx);
608        request.messages.push(LanguageModelRequestMessage {
609            role: Role::User,
610            content: vec![
611                "Generate a concise 3-7 word title for this conversation, omitting punctuation. Go straight to the title, without any preamble and prefix like `Here's a concise suggestion:...` or `Title:`"
612                    .into(),
613            ],
614            cache: false,
615        });
616
617        self.pending_summary = cx.spawn(|this, mut cx| {
618            async move {
619                let stream = model.stream_completion_text(request, &cx);
620                let mut messages = stream.await?;
621
622                let mut new_summary = String::new();
623                while let Some(message) = messages.stream.next().await {
624                    let text = message?;
625                    let mut lines = text.lines();
626                    new_summary.extend(lines.next());
627
628                    // Stop if the LLM generated multiple lines.
629                    if lines.next().is_some() {
630                        break;
631                    }
632                }
633
634                this.update(&mut cx, |this, cx| {
635                    if !new_summary.is_empty() {
636                        this.summary = Some(new_summary.into());
637                    }
638
639                    cx.emit(ThreadEvent::SummaryChanged);
640                })?;
641
642                anyhow::Ok(())
643            }
644            .log_err()
645        });
646    }
647
648    pub fn use_pending_tools(&mut self, cx: &mut Context<Self>) {
649        let request = self.to_completion_request(RequestKind::Chat, cx);
650        let pending_tool_uses = self
651            .tool_use
652            .pending_tool_uses()
653            .into_iter()
654            .filter(|tool_use| tool_use.status.is_idle())
655            .cloned()
656            .collect::<Vec<_>>();
657
658        for tool_use in pending_tool_uses {
659            if let Some(tool) = self.tools.tool(&tool_use.name, cx) {
660                let task = tool.run(tool_use.input, &request.messages, self.project.clone(), cx);
661
662                self.insert_tool_output(tool_use.id.clone(), task, cx);
663            }
664        }
665
666        let pending_scripting_tool_uses = self
667            .scripting_tool_use
668            .pending_tool_uses()
669            .into_iter()
670            .filter(|tool_use| tool_use.status.is_idle())
671            .cloned()
672            .collect::<Vec<_>>();
673
674        for scripting_tool_use in pending_scripting_tool_uses {
675            let task = match ScriptingTool::deserialize_input(scripting_tool_use.input) {
676                Err(err) => Task::ready(Err(err.into())),
677                Ok(input) => {
678                    let (script_id, script_task) =
679                        self.scripting_session.update(cx, move |session, cx| {
680                            session.run_script(input.lua_script, cx)
681                        });
682
683                    let session = self.scripting_session.clone();
684                    cx.spawn(|_, cx| async move {
685                        script_task.await;
686
687                        let message = session.read_with(&cx, |session, _cx| {
688                            // Using a id to get the script output seems impractical.
689                            // Why not just include it in the Task result?
690                            // This is because we'll later report the script state as it runs,
691                            session
692                                .get(script_id)
693                                .output_message_for_llm()
694                                .expect("Script shouldn't still be running")
695                        })?;
696
697                        Ok(message)
698                    })
699                }
700            };
701
702            self.insert_scripting_tool_output(scripting_tool_use.id.clone(), task, cx);
703        }
704    }
705
706    pub fn insert_tool_output(
707        &mut self,
708        tool_use_id: LanguageModelToolUseId,
709        output: Task<Result<String>>,
710        cx: &mut Context<Self>,
711    ) {
712        let insert_output_task = cx.spawn(|thread, mut cx| {
713            let tool_use_id = tool_use_id.clone();
714            async move {
715                let output = output.await;
716                thread
717                    .update(&mut cx, |thread, cx| {
718                        let pending_tool_use = thread
719                            .tool_use
720                            .insert_tool_output(tool_use_id.clone(), output);
721
722                        cx.emit(ThreadEvent::ToolFinished {
723                            tool_use_id,
724                            pending_tool_use,
725                        });
726                    })
727                    .ok();
728            }
729        });
730
731        self.tool_use
732            .run_pending_tool(tool_use_id, insert_output_task);
733    }
734
735    pub fn insert_scripting_tool_output(
736        &mut self,
737        tool_use_id: LanguageModelToolUseId,
738        output: Task<Result<String>>,
739        cx: &mut Context<Self>,
740    ) {
741        let insert_output_task = cx.spawn(|thread, mut cx| {
742            let tool_use_id = tool_use_id.clone();
743            async move {
744                let output = output.await;
745                thread
746                    .update(&mut cx, |thread, cx| {
747                        let pending_tool_use = thread
748                            .scripting_tool_use
749                            .insert_tool_output(tool_use_id.clone(), output);
750
751                        cx.emit(ThreadEvent::ToolFinished {
752                            tool_use_id,
753                            pending_tool_use,
754                        });
755                    })
756                    .ok();
757            }
758        });
759
760        self.scripting_tool_use
761            .run_pending_tool(tool_use_id, insert_output_task);
762    }
763
764    pub fn send_tool_results_to_model(
765        &mut self,
766        model: Arc<dyn LanguageModel>,
767        cx: &mut Context<Self>,
768    ) {
769        // Insert a user message to contain the tool results.
770        self.insert_user_message(
771            // TODO: Sending up a user message without any content results in the model sending back
772            // responses that also don't have any content. We currently don't handle this case well,
773            // so for now we provide some text to keep the model on track.
774            "Here are the tool results.",
775            Vec::new(),
776            cx,
777        );
778        self.send_to_model(model, RequestKind::Chat, cx);
779    }
780
781    /// Cancels the last pending completion, if there are any pending.
782    ///
783    /// Returns whether a completion was canceled.
784    pub fn cancel_last_completion(&mut self) -> bool {
785        if let Some(_last_completion) = self.pending_completions.pop() {
786            true
787        } else {
788            false
789        }
790    }
791}
792
793#[derive(Debug, Clone)]
794pub enum ThreadError {
795    PaymentRequired,
796    MaxMonthlySpendReached,
797    Message(SharedString),
798}
799
800#[derive(Debug, Clone)]
801pub enum ThreadEvent {
802    ShowError(ThreadError),
803    StreamedCompletion,
804    StreamedAssistantText(MessageId, String),
805    MessageAdded(MessageId),
806    MessageEdited(MessageId),
807    MessageDeleted(MessageId),
808    SummaryChanged,
809    UsePendingTools,
810    ToolFinished {
811        #[allow(unused)]
812        tool_use_id: LanguageModelToolUseId,
813        /// The pending tool use that corresponds to this tool.
814        pending_tool_use: Option<PendingToolUse>,
815    },
816}
817
818impl EventEmitter<ThreadEvent> for Thread {}
819
820struct PendingCompletion {
821    id: usize,
822    _task: Task<()>,
823}