Files
Termind/Frameworks/TermindApplication/Agent/AssistantExecutionController.swift
T
2026-09-11 21:07:44 +08:00

419 lines
19 KiB
Swift

import AgentKit
import Foundation
import TermindDomain
/// One runtime assembly and compaction policy for both app surfaces.
@MainActor
public final class AssistantExecutionController {
public typealias RegistryFactory =
@MainActor (ConversationModel, AIModel, ModelProvider, AgentSkillCatalog, AgentEventChannel, Bool) ->
AgentToolRegistry
private let ai: AIConfigurationModel
private let skills: SkillLibraryModel
private let agentRunRepository: any AgentRunPersisting
private let authorize: @MainActor () -> Bool
private let makeRegistry: RegistryFactory
private let title: @MainActor (ConversationTitleContext) async throws -> String
private let agentCompaction = AgentCompactionService()
private var titledConversationIDs = Set<UUID>()
private var preparationGeneration: UInt64 = 0
private var preparing = Set<UUID>()
public func cancelPendingRuns() { preparationGeneration &+= 1 }
public init(
ai: AIConfigurationModel, skills: SkillLibraryModel, repository: any AgentRunPersisting,
authorize: @escaping @MainActor () -> Bool, makeRegistry: @escaping RegistryFactory,
title: @escaping @MainActor (ConversationTitleContext) async throws -> String
) {
self.ai = ai
self.skills = skills
agentRunRepository = repository
self.authorize = authorize
self.makeRegistry = makeRegistry
self.title = title
}
public func sendAgentDraft(
_ conversation: ConversationModel,
context: SessionContext = .none,
includesTerminalSuggestion: Bool = false
) {
guard authorize() else { return }
let draft = conversation.composer.draft.trimmingCharacters(in: .whitespacesAndNewlines)
guard conversation.canSendDraft, !conversation.isArchived, !conversation.isStreaming,
!conversation.isCompacting, !conversation.isHistoryChanging,
conversation.composer.pendingAttachments.isEmpty,
preparing.insert(conversation.id).inserted
else { return }
let generation = preparationGeneration
// The *returned* text, not `draft`: attachments are folded in there, and
// running on the pre-fold string would show the model a turn that does
// not match the one the conversation recorded.
let prompt = conversation.appendUserTurnContent(draft)
conversation.composer.draft = ""
// Compaction happens *after* the turn is recorded and before the run,
// so the message the user just typed is inside the kept window rather
// than being the first thing summarized away. When nothing needs
// compacting this is a synchronous check that starts the run in the same
// tick, which is what keeps the composer feeling immediate.
Task { [weak self, weak conversation] in
guard let self, let conversation else { return }
defer { preparing.remove(conversation.id) }
await compactIfNeeded(conversation)
guard generation == preparationGeneration, !Task.isCancelled else {
do {
try await agentRunRepository.save(
AgentRunSnapshot(
conversationID: conversation.id, state: .interrupted,
permissionMode: ai.resolve(conversation: conversation.permissionMode),
messages: conversation.transcript, finishedAt: .now))
conversation.handle(.runState(.interrupted))
} catch {
conversation.messages.append(ChatMessage(role: .assistant, text: error.localizedDescription))
}
return
}
startAgentRun(
conversation, promptID: prompt.id, prompt: prompt.text,
authoredPrompt: prompt.authoredText, promptImages: prompt.images,
promptContextAttachments: prompt.contextAttachments, context: context,
includesTerminalSuggestion: includesTerminalSuggestion
)
}
}
public func startAgentRun(
_ conversation: ConversationModel,
promptID: UUID? = nil,
prompt: String? = nil,
authoredPrompt: String? = nil,
promptImages: [AgentImageAttachment]? = nil,
promptContextAttachments: [AgentContextAttachment]? = nil,
context: SessionContext = .none,
includesTerminalSuggestion: Bool = false
) {
guard authorize() else { return }
guard !conversation.isStreaming, !conversation.isArchived, !conversation.isHistoryChanging else { return }
let lastUserTurn = conversation.transcript.last(where: { $0.role == .user })
let userPrompt =
prompt
?? lastUserTurn?.text
?? ""
let userImages =
promptImages
?? lastUserTurn?.images
?? []
let userContextAttachments =
promptContextAttachments
?? lastUserTurn?.contextAttachments
?? []
guard !userPrompt.isEmpty || !userImages.isEmpty || !userContextAttachments.isEmpty
else { return }
guard let chat = ai.resolve(conversation: conversation.model) else {
conversation.messages.append(
ChatMessage(
role: .assistant, text: String(localized: "No Chat model is configured.")
))
return
}
guard let secret = ai.secret(for: chat.provider.effectiveCredentialRef), !secret.isEmpty else {
conversation.messages.append(
ChatMessage(
role: .assistant, text: String(localized: "The Chat model has no available credential.")
))
return
}
let mode = ai.resolve(conversation: conversation.permissionMode)
let nativeSearch =
ai.webSearch.isEnabled && ai.webSearch.prefersBuiltIn
&& chat.provider.supportsNativeWebSearch(model: chat.model)
let model = AgentProviderClient(
provider: chat.provider, model: chat.model, secret: secret,
reasoning: conversation.reasoningEffort,
webSearch: nativeSearch
)
let reviewer: (any SecurityReviewing)? = {
guard mode == .approveForMe, let review = ai.resolve(.securityReview) else { return nil }
guard let reviewSecret = ai.secret(for: review.provider.effectiveCredentialRef),
!reviewSecret.isEmpty
else { return nil }
let reasoning = SecurityReviewClient.preferredReasoning(
model: review.model, provider: review.provider
)
return SecurityReviewClient(
model: AgentProviderClient(
provider: review.provider, model: review.model, secret: reviewSecret,
reasoning: reasoning
))
}()
// One channel for the whole run, shared by everything that publishes
// into it. The broker used to raise its review events through a closure
// of its own, each wrapped in an unstructured `Task` — so a review's
// events had no defined order against the tool events they belong
// between, and its durable writes had no defined order against
// anything. See `AgentEventChannel`.
let channel = AgentEventChannel(repository: agentRunRepository)
// Weakly. The conversation owns the runtime, the runtime owns the broker
// and the interaction handler, and both of those used to own the
// conversation back — so every chat that had ever run an agent stayed
// alive, with its runtime, for the life of the process. A conversation
// that is gone denies and cancels: fail closed.
let approval = AgentApprovalBroker(
reviewer: reviewer,
manualApproval: { [weak conversation] request in
guard let conversation else {
return .deny(String(localized: "The conversation was closed before this action was approved."))
}
return await conversation.requestApproval(request)
},
event: channel.emit
)
// Read once, here, for the reason `isPlanning` below is: a run's posture
// is fixed when it starts, so enabling a skill while the agent is
// thinking must not change what this run was told it had. Empty when the
// model cannot call tools, which is what keeps the catalog block from
// naming a tool this run was never given.
let skillCatalog =
chat.model.abilities.contains(.toolCall)
? skills.catalog : AgentSkillCatalog()
let registry = makeRegistry(
conversation, chat.model, chat.provider, skillCatalog, channel, includesTerminalSuggestion)
// The one place the resolved tool set exists. Recorded on the
// conversation so the context gauge can account for the schemas without
// rebuilding a registry on every keystroke.
conversation.noteToolSchemas(registry.descriptors)
// Read once, here: the posture a run enforces is the one it started
// under, and the user is free to leave plan mode while it is thinking.
let isPlanning = conversation.isPlanning
// The catalog reaches the model boundary through the pipeline rather
// than through the system prompt, so the prompt stays byte-identical for
// every run and the provider's prefix cache survives a skill being
// enabled. See `AgentSkillCatalogInjection`.
var configuration = AgentLoopConfiguration()
// Termind draws the reply as it streams, so the bursts a provider
// delivers in need smoothing before they reach a view. A surface that
// only records events would leave this off — see `AgentStreamPacing`.
configuration.streamPacing = .animated
configuration.contextPipeline = { sessionContext, promptID, planning in
AgentContextPipeline.chat(
sessionContext: sessionContext, before: promptID,
isPlanning: planning, skills: skillCatalog,
planContract: TermindAgentPolicy.planContract
)
}
let interaction = WeakAgentUserInteraction(conversation)
let runtime = AgentRuntime(
model: model, registry: registry,
approval: approval,
repository: agentRunRepository,
userInteraction: interaction,
services: AgentToolServices()
.setting(interaction.sshInteraction, for: .sshInteraction),
hooks: [TermindAgentPolicy.planModeHook(isPlanning: isPlanning)],
configuration: configuration,
channel: channel
)
// No second Shell Integration gate here. `Pane.remoteSystemInfo` already
// withholds the probe when the setting is off, and `context` is the same
// value the chips were drawn from — so what is shown and what is sent
// cannot disagree.
conversation.start(
runtime: runtime,
request: AgentRunRequest(
conversationID: conversation.id,
promptID: promptID ?? lastUserTurn?.id ?? UUID(), prompt: userPrompt,
authoredPrompt: authoredPrompt ?? lastUserTurn?.authoredText,
promptImages: userImages,
promptContextAttachments: userContextAttachments,
permissionMode: mode, isPlanning: isPlanning,
systemPrompt: TermindAgentPolicy.systemPrompt,
priorMessages: conversation.pendingPriorMessages,
sessionContext: context.modelContext
))
scheduleTitle(for: conversation)
}
/// Which of the two web-search paths this turn gets, resolved once so the
/// request body and the tool list cannot disagree.
///
/// Native wins where it exists. It searches better than a snippet API can,
/// costs no second key, and needs no round trip through Termind — the model
/// simply knows things. What it gives up is visibility, which
/// `AgentRuntime.recordNativeWebSearch` buys back after the fact.
///
// MARK: - Compaction
/// Summarizes the older part of a conversation so it can keep going.
///
/// Never while a run is in flight: the transcript it would rewrite is the
/// one the runtime is appending to, and the two would disagree about what
/// the conversation is. `/compact` during a run is refused rather than
/// queued, because by the time the run ends the thing the user wanted
/// compacted has changed.
@discardableResult
public func compact(
_ conversation: ConversationModel,
instructions: String = "",
isManual: Bool = true
) async -> Bool {
guard authorize() else { return false }
guard !conversation.isStreaming, !conversation.isCompacting else { return false }
conversation.beginCompaction()
guard
let span = conversation.compactionSpan(
keepRecentTokens: compactionBudget.keepRecentTokens
)
else {
if isManual {
conversation.failCompaction(
AgentCompactionError.nothingToCompact.localizedDescription
)
} else {
conversation.endCompaction()
}
return false
}
guard let model = compactionModel() else {
conversation.failCompaction(AgentCompactionError.missingModel.localizedDescription)
return false
}
do {
let summary = try await agentCompaction.summarize(
span.summarize, instructions: instructions,
toolResultLimit: compactionBudget.toolResultLimit, model: model
)
guard
let record = conversation.prepareCompaction(
summary: summary, cut: span.cut
)
else {
throw AgentCompactionError.nothingToCompact
}
try await persistAndApplyCompaction(record, to: conversation, cut: span.cut)
conversation.endCompaction()
return true
} catch {
conversation.failCompaction(error.localizedDescription)
return false
}
}
/// The atomicity boundary for compaction: persistence happens first, and
/// the observable model changes only after that succeeds.
public func persistAndApplyCompaction(
_ record: AgentCompactionRecord, to conversation: ConversationModel, cut: Int
) async throws {
try await agentRunRepository.persistCompaction(
record, conversationID: conversation.id
)
conversation.applyCompaction(record, cut: cut)
}
/// Compacts before a run when the conversation is close to the window.
///
/// Threshold only. Recovering a turn that has *already* overflowed means
/// recognising four providers' distinct context-length errors, which is its
/// own piece of work — this is what keeps a conversation from getting there.
private func compactIfNeeded(_ conversation: ConversationModel) async {
guard let usage = conversation.usage else { return }
let window = ai.resolve(conversation: conversation.model)?.model.contextLength
guard
AgentCompaction.shouldCompact(
contextTokens: usage.contextTokens, contextWindow: window,
reserveTokens: compactionBudget.reserveTokens
)
else { return }
await compact(conversation, isManual: false)
}
/// Resolves the Chat model with reasoning clamped off, like titling does.
///
/// Summarizing is not a task that improves with a thinking budget, and this
/// runs on the user's own key at the moment their conversation is already
/// expensive.
private func compactionModel() -> (any AgentModelCompleting)? {
guard let resolved = ai.resolve(.chat) else { return nil }
guard let secret = ai.secret(for: resolved.provider.effectiveCredentialRef), !secret.isEmpty
else { return nil }
let reasoning = ModelCapabilityResolver.reasoning(
model: resolved.model, provider: resolved.provider
).clamp(.off)
return AgentProviderClient(
provider: resolved.provider, model: resolved.model, secret: secret,
reasoning: reasoning
)
}
/// What a compaction is allowed to keep, reserve, and show the summarizer.
///
/// One value rather than three, so a future Settings control changes them
/// together — see `AgentCompaction.Budget`. Termind ships the defaults.
private var compactionBudget: AgentCompaction.Budget { .default }
/// Exactly one path is ever live. Offering both would put two tools in
/// front of the model for one job and leave it to guess which, and the
/// guess would decide whether the search shows up as a card beforehand or a
/// record afterwards.
/// Arms the one-shot summary for this conversation.
///
/// Titling is deliberately once per conversation, not per run: a chat list
/// whose rows rewrite themselves as the conversation grows is harder to scan
/// than one whose rows stay put. `titledConversationIDs` is what makes the
/// second run a no-op even though every run re-arms the hook.
private func scheduleTitle(for conversation: ConversationModel) {
conversation.runDidFinish = { [weak self, weak conversation] in
guard let self, let conversation,
let context = Self.titleContext(for: conversation),
!titledConversationIDs.contains(conversation.id)
else { return }
titledConversationIDs.insert(conversation.id)
Task { [weak self, weak conversation] in
guard let self else { return }
guard let title = try? await title(context),
let conversation
else { return }
do {
try await agentRunRepository.setTitle(title, conversationID: conversation.id)
conversation.title = title
} catch {
titledConversationIDs.remove(conversation.id)
}
}
}
}
/// The opening exchange, if this conversation has one worth naming.
///
/// Read from `transcript`, not `messages`. A run that failed puts its reason
/// in the visible list alone, so gating on `messages` would happily title a
/// conversation "The Chat model has no available credential."
///
/// Gated on there being a reply rather than on the run having *completed*,
/// so a run the user stopped after a full first answer still gets a title
/// instead of staying labelled by its opening line forever.
public static func titleContext(for conversation: ConversationModel) -> ConversationTitleContext? {
guard conversation.title == nil,
let firstUser = conversation.transcript.first(where: { $0.role == .user }),
let assistant = conversation.transcript.first(where: {
$0.role == .assistant && !$0.text.isEmpty
})?.text
else { return nil }
let user =
firstUser.text.isEmpty
? firstUser.images.first?.label
?? firstUser.contextAttachments.first?.label
?? ""
: firstUser.text
guard !user.isEmpty else { return nil }
return ConversationTitleContext(
firstUserMessage: user, firstAssistantMessage: assistant
)
}
}