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::{AssistantSystemPromptWorktree, 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            .visible_worktrees(cx)
388            .map(|worktree| {
389                let worktree = worktree.read(cx);
390                AssistantSystemPromptWorktree {
391                    root_name: worktree.root_name().into(),
392                    abs_path: worktree.abs_path(),
393                }
394            })
395            .collect::<Vec<_>>();
396        let system_prompt = self
397            .prompt_builder
398            .generate_assistant_system_prompt(worktree_root_names)
399            .context("failed to generate assistant system prompt")
400            .log_err()
401            .unwrap_or_default();
402
403        let mut request = LanguageModelRequest {
404            messages: vec![LanguageModelRequestMessage {
405                role: Role::System,
406                content: vec![MessageContent::Text(system_prompt)],
407                cache: true,
408            }],
409            tools: Vec::new(),
410            stop: Vec::new(),
411            temperature: None,
412        };
413
414        let mut referenced_context_ids = HashSet::default();
415
416        for message in &self.messages {
417            if let Some(context_ids) = self.context_by_message.get(&message.id) {
418                referenced_context_ids.extend(context_ids);
419            }
420
421            let mut request_message = LanguageModelRequestMessage {
422                role: message.role,
423                content: Vec::new(),
424                cache: false,
425            };
426
427            match request_kind {
428                RequestKind::Chat => {
429                    self.tool_use
430                        .attach_tool_results(message.id, &mut request_message);
431                    self.scripting_tool_use
432                        .attach_tool_results(message.id, &mut request_message);
433                }
434                RequestKind::Summarize => {
435                    // We don't care about tool use during summarization.
436                }
437            }
438
439            if !message.text.is_empty() {
440                request_message
441                    .content
442                    .push(MessageContent::Text(message.text.clone()));
443            }
444
445            match request_kind {
446                RequestKind::Chat => {
447                    self.tool_use
448                        .attach_tool_uses(message.id, &mut request_message);
449                    self.scripting_tool_use
450                        .attach_tool_uses(message.id, &mut request_message);
451                }
452                RequestKind::Summarize => {
453                    // We don't care about tool use during summarization.
454                }
455            };
456
457            request.messages.push(request_message);
458        }
459
460        if !referenced_context_ids.is_empty() {
461            let mut context_message = LanguageModelRequestMessage {
462                role: Role::User,
463                content: Vec::new(),
464                cache: false,
465            };
466
467            let referenced_context = referenced_context_ids
468                .into_iter()
469                .filter_map(|context_id| self.context.get(context_id))
470                .cloned();
471            attach_context_to_message(&mut context_message, referenced_context);
472
473            request.messages.push(context_message);
474        }
475
476        request
477    }
478
479    pub fn stream_completion(
480        &mut self,
481        request: LanguageModelRequest,
482        model: Arc<dyn LanguageModel>,
483        cx: &mut Context<Self>,
484    ) {
485        let pending_completion_id = post_inc(&mut self.completion_count);
486
487        let task = cx.spawn(|thread, mut cx| async move {
488            let stream = model.stream_completion(request, &cx);
489            let stream_completion = async {
490                let mut events = stream.await?;
491                let mut stop_reason = StopReason::EndTurn;
492
493                while let Some(event) = events.next().await {
494                    let event = event?;
495
496                    thread.update(&mut cx, |thread, cx| {
497                        match event {
498                            LanguageModelCompletionEvent::StartMessage { .. } => {
499                                thread.insert_message(Role::Assistant, String::new(), cx);
500                            }
501                            LanguageModelCompletionEvent::Stop(reason) => {
502                                stop_reason = reason;
503                            }
504                            LanguageModelCompletionEvent::Text(chunk) => {
505                                if let Some(last_message) = thread.messages.last_mut() {
506                                    if last_message.role == Role::Assistant {
507                                        last_message.text.push_str(&chunk);
508                                        cx.emit(ThreadEvent::StreamedAssistantText(
509                                            last_message.id,
510                                            chunk,
511                                        ));
512                                    } else {
513                                        // If we won't have an Assistant message yet, assume this chunk marks the beginning
514                                        // of a new Assistant response.
515                                        //
516                                        // Importantly: We do *not* want to emit a `StreamedAssistantText` event here, as it
517                                        // will result in duplicating the text of the chunk in the rendered Markdown.
518                                        thread.insert_message(Role::Assistant, chunk, cx);
519                                    };
520                                }
521                            }
522                            LanguageModelCompletionEvent::ToolUse(tool_use) => {
523                                if let Some(last_assistant_message) = thread
524                                    .messages
525                                    .iter()
526                                    .rfind(|message| message.role == Role::Assistant)
527                                {
528                                    if tool_use.name.as_ref() == ScriptingTool::NAME {
529                                        thread
530                                            .scripting_tool_use
531                                            .request_tool_use(last_assistant_message.id, tool_use);
532                                    } else {
533                                        thread
534                                            .tool_use
535                                            .request_tool_use(last_assistant_message.id, tool_use);
536                                    }
537                                }
538                            }
539                        }
540
541                        thread.touch_updated_at();
542                        cx.emit(ThreadEvent::StreamedCompletion);
543                        cx.notify();
544                    })?;
545
546                    smol::future::yield_now().await;
547                }
548
549                thread.update(&mut cx, |thread, cx| {
550                    thread
551                        .pending_completions
552                        .retain(|completion| completion.id != pending_completion_id);
553
554                    if thread.summary.is_none() && thread.messages.len() >= 2 {
555                        thread.summarize(cx);
556                    }
557                })?;
558
559                anyhow::Ok(stop_reason)
560            };
561
562            let result = stream_completion.await;
563
564            thread
565                .update(&mut cx, |thread, cx| match result.as_ref() {
566                    Ok(stop_reason) => match stop_reason {
567                        StopReason::ToolUse => {
568                            cx.emit(ThreadEvent::UsePendingTools);
569                        }
570                        StopReason::EndTurn => {}
571                        StopReason::MaxTokens => {}
572                    },
573                    Err(error) => {
574                        if error.is::<PaymentRequiredError>() {
575                            cx.emit(ThreadEvent::ShowError(ThreadError::PaymentRequired));
576                        } else if error.is::<MaxMonthlySpendReachedError>() {
577                            cx.emit(ThreadEvent::ShowError(ThreadError::MaxMonthlySpendReached));
578                        } else {
579                            let error_message = error
580                                .chain()
581                                .map(|err| err.to_string())
582                                .collect::<Vec<_>>()
583                                .join("\n");
584                            cx.emit(ThreadEvent::ShowError(ThreadError::Message(
585                                SharedString::from(error_message.clone()),
586                            )));
587                        }
588
589                        thread.cancel_last_completion();
590                    }
591                })
592                .ok();
593        });
594
595        self.pending_completions.push(PendingCompletion {
596            id: pending_completion_id,
597            _task: task,
598        });
599    }
600
601    pub fn summarize(&mut self, cx: &mut Context<Self>) {
602        let Some(provider) = LanguageModelRegistry::read_global(cx).active_provider() else {
603            return;
604        };
605        let Some(model) = LanguageModelRegistry::read_global(cx).active_model() else {
606            return;
607        };
608
609        if !provider.is_authenticated(cx) {
610            return;
611        }
612
613        let mut request = self.to_completion_request(RequestKind::Summarize, cx);
614        request.messages.push(LanguageModelRequestMessage {
615            role: Role::User,
616            content: vec![
617                "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:`"
618                    .into(),
619            ],
620            cache: false,
621        });
622
623        self.pending_summary = cx.spawn(|this, mut cx| {
624            async move {
625                let stream = model.stream_completion_text(request, &cx);
626                let mut messages = stream.await?;
627
628                let mut new_summary = String::new();
629                while let Some(message) = messages.stream.next().await {
630                    let text = message?;
631                    let mut lines = text.lines();
632                    new_summary.extend(lines.next());
633
634                    // Stop if the LLM generated multiple lines.
635                    if lines.next().is_some() {
636                        break;
637                    }
638                }
639
640                this.update(&mut cx, |this, cx| {
641                    if !new_summary.is_empty() {
642                        this.summary = Some(new_summary.into());
643                    }
644
645                    cx.emit(ThreadEvent::SummaryChanged);
646                })?;
647
648                anyhow::Ok(())
649            }
650            .log_err()
651        });
652    }
653
654    pub fn use_pending_tools(&mut self, cx: &mut Context<Self>) {
655        let request = self.to_completion_request(RequestKind::Chat, cx);
656        let pending_tool_uses = self
657            .tool_use
658            .pending_tool_uses()
659            .into_iter()
660            .filter(|tool_use| tool_use.status.is_idle())
661            .cloned()
662            .collect::<Vec<_>>();
663
664        for tool_use in pending_tool_uses {
665            if let Some(tool) = self.tools.tool(&tool_use.name, cx) {
666                let task = tool.run(tool_use.input, &request.messages, self.project.clone(), cx);
667
668                self.insert_tool_output(tool_use.id.clone(), task, cx);
669            }
670        }
671
672        let pending_scripting_tool_uses = self
673            .scripting_tool_use
674            .pending_tool_uses()
675            .into_iter()
676            .filter(|tool_use| tool_use.status.is_idle())
677            .cloned()
678            .collect::<Vec<_>>();
679
680        for scripting_tool_use in pending_scripting_tool_uses {
681            let task = match ScriptingTool::deserialize_input(scripting_tool_use.input) {
682                Err(err) => Task::ready(Err(err.into())),
683                Ok(input) => {
684                    let (script_id, script_task) =
685                        self.scripting_session.update(cx, move |session, cx| {
686                            session.run_script(input.lua_script, cx)
687                        });
688
689                    let session = self.scripting_session.clone();
690                    cx.spawn(|_, cx| async move {
691                        script_task.await;
692
693                        let message = session.read_with(&cx, |session, _cx| {
694                            // Using a id to get the script output seems impractical.
695                            // Why not just include it in the Task result?
696                            // This is because we'll later report the script state as it runs,
697                            session
698                                .get(script_id)
699                                .output_message_for_llm()
700                                .expect("Script shouldn't still be running")
701                        })?;
702
703                        Ok(message)
704                    })
705                }
706            };
707
708            self.insert_scripting_tool_output(scripting_tool_use.id.clone(), task, cx);
709        }
710    }
711
712    pub fn insert_tool_output(
713        &mut self,
714        tool_use_id: LanguageModelToolUseId,
715        output: Task<Result<String>>,
716        cx: &mut Context<Self>,
717    ) {
718        let insert_output_task = cx.spawn(|thread, mut cx| {
719            let tool_use_id = tool_use_id.clone();
720            async move {
721                let output = output.await;
722                thread
723                    .update(&mut cx, |thread, cx| {
724                        let pending_tool_use = thread
725                            .tool_use
726                            .insert_tool_output(tool_use_id.clone(), output);
727
728                        cx.emit(ThreadEvent::ToolFinished {
729                            tool_use_id,
730                            pending_tool_use,
731                        });
732                    })
733                    .ok();
734            }
735        });
736
737        self.tool_use
738            .run_pending_tool(tool_use_id, insert_output_task);
739    }
740
741    pub fn insert_scripting_tool_output(
742        &mut self,
743        tool_use_id: LanguageModelToolUseId,
744        output: Task<Result<String>>,
745        cx: &mut Context<Self>,
746    ) {
747        let insert_output_task = cx.spawn(|thread, mut cx| {
748            let tool_use_id = tool_use_id.clone();
749            async move {
750                let output = output.await;
751                thread
752                    .update(&mut cx, |thread, cx| {
753                        let pending_tool_use = thread
754                            .scripting_tool_use
755                            .insert_tool_output(tool_use_id.clone(), output);
756
757                        cx.emit(ThreadEvent::ToolFinished {
758                            tool_use_id,
759                            pending_tool_use,
760                        });
761                    })
762                    .ok();
763            }
764        });
765
766        self.scripting_tool_use
767            .run_pending_tool(tool_use_id, insert_output_task);
768    }
769
770    pub fn send_tool_results_to_model(
771        &mut self,
772        model: Arc<dyn LanguageModel>,
773        cx: &mut Context<Self>,
774    ) {
775        // Insert a user message to contain the tool results.
776        self.insert_user_message(
777            // TODO: Sending up a user message without any content results in the model sending back
778            // responses that also don't have any content. We currently don't handle this case well,
779            // so for now we provide some text to keep the model on track.
780            "Here are the tool results.",
781            Vec::new(),
782            cx,
783        );
784        self.send_to_model(model, RequestKind::Chat, cx);
785    }
786
787    /// Cancels the last pending completion, if there are any pending.
788    ///
789    /// Returns whether a completion was canceled.
790    pub fn cancel_last_completion(&mut self) -> bool {
791        if let Some(_last_completion) = self.pending_completions.pop() {
792            true
793        } else {
794            false
795        }
796    }
797}
798
799#[derive(Debug, Clone)]
800pub enum ThreadError {
801    PaymentRequired,
802    MaxMonthlySpendReached,
803    Message(SharedString),
804}
805
806#[derive(Debug, Clone)]
807pub enum ThreadEvent {
808    ShowError(ThreadError),
809    StreamedCompletion,
810    StreamedAssistantText(MessageId, String),
811    MessageAdded(MessageId),
812    MessageEdited(MessageId),
813    MessageDeleted(MessageId),
814    SummaryChanged,
815    UsePendingTools,
816    ToolFinished {
817        #[allow(unused)]
818        tool_use_id: LanguageModelToolUseId,
819        /// The pending tool use that corresponds to this tool.
820        pending_tool_use: Option<PendingToolUse>,
821    },
822}
823
824impl EventEmitter<ThreadEvent> for Thread {}
825
826struct PendingCompletion {
827    id: usize,
828    _task: Task<()>,
829}