| 1 | package agent |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "errors" |
| 6 | "fmt" |
| 7 | "slices" |
| 8 | "strings" |
| 9 | |
| 10 | "reasonix/internal/event" |
| 11 | "reasonix/internal/provider" |
| 12 | "reasonix/internal/tool" |
| 13 | ) |
| 14 | |
| 15 | const ( |
| 16 | maxCompressAnchorBytes = 512 |
| 17 | maxCompressFocusBytes = 2000 |
| 18 | ) |
| 19 | |
| 20 | var errCompressStaleContext = errors.New("compress: conversation changed while compression was running; retry with the current context") |
| 21 | |
| 22 | // CompressContext implements the context-bound compress tool. It resolves the |
| 23 | // anchor against the current model-visible view and installs a projection only; |
| 24 | // the canonical transcript and checkpoint lineage remain untouched. |
| 25 | func (a *Agent) CompressContext(ctx context.Context, req tool.CompressRequest) (tool.CompressResult, error) { |
| 26 | direction := strings.TrimSpace(req.Direction) |
| 27 | anchor := strings.TrimSpace(req.Anchor) |
| 28 | focus := strings.TrimSpace(req.Focus) |
| 29 | if direction != "before" && direction != "after" { |
| 30 | return tool.CompressResult{}, fmt.Errorf("compress: direction must be before or after") |
| 31 | } |
| 32 | if anchor == "" { |
| 33 | return tool.CompressResult{}, fmt.Errorf("compress: anchor must not be empty") |
| 34 | } |
| 35 | if len(anchor) > maxCompressAnchorBytes { |
| 36 | return tool.CompressResult{}, fmt.Errorf("compress: anchor exceeds %d bytes", maxCompressAnchorBytes) |
| 37 | } |
| 38 | if len(focus) > maxCompressFocusBytes { |
| 39 | return tool.CompressResult{}, fmt.Errorf("compress: focus exceeds %d bytes", maxCompressFocusBytes) |
| 40 | } |
| 41 | |
| 42 | snap := a.snapshotExplicitCompression() |
| 43 | matches := make([]int, 0, 2) |
| 44 | for i, msg := range snap.visible { |
| 45 | if !compressAnchorCandidate(msg) { |
| 46 | continue |
| 47 | } |
| 48 | if strings.Contains(UserMessageText(msg), anchor) { |
| 49 | matches = append(matches, i) |
| 50 | } |
| 51 | } |
| 52 | if len(matches) == 0 { |
| 53 | return tool.CompressResult{}, fmt.Errorf("compress: anchor did not match any current user message; retry with an exact excerpt from a visible user turn") |
| 54 | } |
| 55 | if len(matches) > 1 { |
| 56 | return tool.CompressResult{}, fmt.Errorf("compress: anchor matched %d user messages; retry with a longer unique excerpt", len(matches)) |
| 57 | } |
| 58 | |
| 59 | return a.compressVisibleRange(ctx, snap, CompactionTriggerTool, direction, matches[0], anchorPreview(UserMessageText(snap.visible[matches[0]])), focus) |
| 60 | } |
| 61 | |
| 62 | type explicitCompressionSnapshot struct { |
| 63 | canonical []provider.Message |
| 64 | visible []provider.Message |
| 65 | transcriptVersion uint64 |
| 66 | coveredHash string |
| 67 | projectionVersion uint64 |
| 68 | generation uint64 |
| 69 | promptCacheKey string |
| 70 | } |
| 71 | |
| 72 | func (a *Agent) snapshotExplicitCompression() explicitCompressionSnapshot { |
| 73 | canonical, version := a.sess.conversation.snapshotMessagesVersion() |
| 74 | cacheKey := a.currentPromptCacheKey() |
| 75 | a.sess.compactionMu.Lock() |
| 76 | state := a.sess.compactionState |
| 77 | a.sess.compactionMu.Unlock() |
| 78 | visible := canonical |
| 79 | if projectionValid(state, canonical, cacheKey) { |
| 80 | if projected := modelVisibleFromProjection(state.Projection, canonical); len(projected) > 0 { |
| 81 | visible = projected |
| 82 | } |
| 83 | } |
| 84 | return explicitCompressionSnapshot{ |
| 85 | canonical: canonical, |
| 86 | visible: compressionVisibleMessages(visible), |
| 87 | transcriptVersion: version, |
| 88 | coveredHash: coveredPrefixHash(canonical, len(canonical)), |
| 89 | projectionVersion: state.Projection.ProjectionVersion, |
| 90 | generation: state.Generation, |
| 91 | promptCacheKey: cacheKey, |
| 92 | } |
| 93 | } |
| 94 | |
| 95 | func compressionVisibleMessages(msgs []provider.Message) []provider.Message { |
| 96 | out := make([]provider.Message, 0, len(msgs)+1) |
| 97 | for _, msg := range msgs { |
| 98 | if !msg.LocalOnly { |
| 99 | summary, user, split := splitLegacyCoalescedSummary(msg) |
| 100 | if split { |
| 101 | out = append(out, summary, user) |
| 102 | } else { |
| 103 | out = append(out, msg) |
| 104 | } |
| 105 | } |
| 106 | } |
| 107 | return out |
| 108 | } |
| 109 | |
| 110 | // Older schema-v1 sidecars may have persisted a strict-role merge of the |
| 111 | // summary and its following user turn. Split that legacy shape for range |
| 112 | // planning; new sidecars keep the logical messages separate and coalesce only |
| 113 | // on the provider request copy. |
| 114 | func splitLegacyCoalescedSummary(msg provider.Message) (provider.Message, provider.Message, bool) { |
| 115 | if !isCompactionSummary(msg) { |
| 116 | return provider.Message{}, provider.Message{}, false |
| 117 | } |
| 118 | separator := summaryTagClose + "\n\n" |
| 119 | i := strings.Index(msg.Content, separator) |
| 120 | if i < 0 || i+len(separator) >= len(msg.Content) { |
| 121 | return provider.Message{}, provider.Message{}, false |
| 122 | } |
| 123 | summary := msg |
| 124 | summary.Origin = provider.MessageOriginHost |
| 125 | summary.Content = msg.Content[:i+len(summaryTagClose)] |
| 126 | summary.RawContent = "" |
| 127 | summary.Images = nil |
| 128 | summary.ImageInputs = nil |
| 129 | summary.ToolCalls = nil |
| 130 | summary.ResponsesItems = nil |
| 131 | summary.ServerSearch = nil |
| 132 | summary.CreatedAt = 0 |
| 133 | user := msg |
| 134 | // The legacy coalesced record did not retain the following turn's |
| 135 | // provenance. Empty keeps old-session fallback available instead of |
| 136 | // asserting that an old host continuation was user-authored. |
| 137 | user.Origin = "" |
| 138 | user.Content = msg.Content[i+len(separator):] |
| 139 | user.RawContent = "" |
| 140 | return summary, user, true |
| 141 | } |
| 142 | |
| 143 | func compressAnchorCandidate(msg provider.Message) bool { |
| 144 | if msg.Role != provider.RoleUser || msg.LocalOnly || isCompactionSummary(msg) { |
| 145 | return false |
| 146 | } |
| 147 | return IsUserAuthoredTurnMessage(msg) |
| 148 | } |
| 149 | |
| 150 | func anchorPreview(text string) string { |
| 151 | return truncatePreview(previewProse(text)) |
| 152 | } |
| 153 | |
| 154 | type visibleCompressionPlan struct { |
| 155 | result tool.CompressResult |
| 156 | foldMask []bool |
| 157 | dropMask []bool |
| 158 | fold []provider.Message |
| 159 | firstFold int |
| 160 | } |
| 161 | |
| 162 | type preparedVisibleCompression struct { |
| 163 | fold []provider.Message |
| 164 | instructions string |
| 165 | inputMode string |
| 166 | } |
| 167 | |
| 168 | func (a *Agent) compressVisibleRange( |
| 169 | ctx context.Context, |
| 170 | snap explicitCompressionSnapshot, |
| 171 | trigger string, |
| 172 | direction string, |
| 173 | anchorIndex int, |
| 174 | preview string, |
| 175 | instructions string, |
| 176 | ) (tool.CompressResult, error) { |
| 177 | a.sess.compactionRunMu.Lock() |
| 178 | defer a.sess.compactionRunMu.Unlock() |
| 179 | if !a.explicitCompressionSnapshotCurrent(snap) { |
| 180 | return tool.CompressResult{}, errCompressStaleContext |
| 181 | } |
| 182 | plan, ok := a.planVisibleCompression(snap, direction, anchorIndex, preview) |
| 183 | if !ok { |
| 184 | return plan.result, nil |
| 185 | } |
| 186 | result := plan.result |
| 187 | inputMode := SummaryInputNonPrefix |
| 188 | if direction == "before" && foldMatchesVisiblePrefix(snap.visible, plan.fold) { |
| 189 | inputMode = SummaryInputCachePrefix |
| 190 | } |
| 191 | |
| 192 | a.svc.sink.Emit(event.Event{Kind: event.CompactionStarted, Compaction: event.Compaction{Trigger: trigger}}) |
| 193 | prepared, reason, err := a.prepareVisibleCompression(ctx, trigger, plan.fold, instructions, inputMode) |
| 194 | if err != nil { |
| 195 | a.emitCompactionAborted(trigger) |
| 196 | return tool.CompressResult{}, err |
| 197 | } |
| 198 | if reason != "" { |
| 199 | a.emitCompactionAborted(trigger) |
| 200 | result.Reason = reason |
| 201 | return result, nil |
| 202 | } |
| 203 | |
| 204 | res, err := a.foldToSummaryMode(ctx, prepared.fold, prepared.instructions, prepared.inputMode) |
| 205 | summary := res.Text |
| 206 | tele := compactionTelemetryFromSummary(trigger, a.CacheState(), result.SourceTokens, res) |
| 207 | if err != nil { |
| 208 | tele.Error = err.Error() |
| 209 | a.emitCompactionTelemetry(tele) |
| 210 | a.emitCompactionAborted(trigger) |
| 211 | return tool.CompressResult{}, err |
| 212 | } |
| 213 | summary, err = a.interceptCompactionComplete(ctx, summary) |
| 214 | if err != nil { |
| 215 | tele.Error = err.Error() |
| 216 | a.emitCompactionTelemetry(tele) |
| 217 | a.emitCompactionAborted(trigger) |
| 218 | return tool.CompressResult{}, err |
| 219 | } |
| 220 | |
| 221 | projection := buildVisibleCompressionProjection(snap.visible, plan, summary) |
| 222 | projection, pinnedCheckpoint, err := rebasePinnedContextProjection(projection, snap.canonical, len(snap.canonical)) |
| 223 | if err != nil { |
| 224 | a.emitCompactionAborted(trigger) |
| 225 | return tool.CompressResult{}, err |
| 226 | } |
| 227 | projectionTokens := a.estimatedVisibleRequestTokens(projection) |
| 228 | tele.ProjectionTokens = projectionTokens |
| 229 | result.Messages = len(plan.fold) |
| 230 | result.ProjectionTokens = projectionTokens |
| 231 | result.Mode = res.Mode |
| 232 | if projectionTokens >= result.SourceTokens { |
| 233 | if pinnedCheckpoint { |
| 234 | result.Reason = "pinned-context-too-large: checkpoint prevents compaction from reducing context" |
| 235 | a.emitCompactionTelemetry(tele) |
| 236 | a.emitCompactionAborted(trigger) |
| 237 | return result, nil |
| 238 | } |
| 239 | result.Reason = "compressed context would not be smaller" |
| 240 | a.emitCompactionTelemetry(tele) |
| 241 | a.emitCompactionAborted(trigger) |
| 242 | return result, nil |
| 243 | } |
| 244 | |
| 245 | inputHash := providerVisibleFingerprint(modelInputMessages(snap.visible)) |
| 246 | outputHash := providerVisibleFingerprint(projection) |
| 247 | state, err := a.commitSummaryProjection(summaryProjectionCommit{ |
| 248 | canonical: snap.canonical, fold: prepared.fold, projected: projection, result: res, |
| 249 | transcriptVersion: snap.transcriptVersion, projectionVersion: snap.projectionVersion, generation: snap.generation, |
| 250 | activeTurn: a.activeTurnCreatedAt.Load(), trigger: trigger, summary: summary, |
| 251 | inputHash: inputHash, outputHash: outputHash, sourceTokens: result.SourceTokens, projectionTokens: projectionTokens, |
| 252 | covered: len(snap.canonical), |
| 253 | }) |
| 254 | if err != nil { |
| 255 | if errors.Is(err, errCompressStaleContext) { |
| 256 | tele.Error = err.Error() |
| 257 | a.emitCompactionTelemetry(tele) |
| 258 | } |
| 259 | a.emitCompactionAborted(trigger) |
| 260 | return tool.CompressResult{}, err |
| 261 | } |
| 262 | a.emitCompactionTelemetry(tele) |
| 263 | a.svc.sink.Emit(event.Event{Kind: event.CompactionDone, Compaction: event.Compaction{ |
| 264 | Trigger: trigger, Messages: len(plan.fold), Summary: summary, Archive: state.LastReceipt.Archive, |
| 265 | }}) |
| 266 | result.Status = "ok" |
| 267 | result.Reason = "" |
| 268 | return result, nil |
| 269 | } |
| 270 | |
| 271 | func foldMatchesVisiblePrefix(visible, fold []provider.Message) bool { |
| 272 | head := 0 |
| 273 | if len(visible) > 0 && visible[0].Role == provider.RoleSystem { |
| 274 | head = 1 |
| 275 | } |
| 276 | if len(fold) == 0 || head+len(fold) > len(visible) { |
| 277 | return false |
| 278 | } |
| 279 | return providerVisibleFingerprint(modelInputMessages(fold)) == |
| 280 | providerVisibleFingerprint(modelInputMessages(visible[head:head+len(fold)])) |
| 281 | } |
| 282 | |
| 283 | func (a *Agent) explicitCompressionSnapshotCurrent(snap explicitCompressionSnapshot) bool { |
| 284 | current, version := a.sess.conversation.snapshotMessagesVersion() |
| 285 | a.sess.compactionMu.Lock() |
| 286 | projectionVersion := a.sess.compactionState.Projection.ProjectionVersion |
| 287 | generation := a.sess.compactionState.Generation |
| 288 | a.sess.compactionMu.Unlock() |
| 289 | return version == snap.transcriptVersion && len(current) == len(snap.canonical) && |
| 290 | coveredPrefixHash(current, len(current)) == snap.coveredHash && |
| 291 | projectionVersion == snap.projectionVersion && generation == snap.generation && |
| 292 | a.currentPromptCacheKey() == snap.promptCacheKey |
| 293 | } |
| 294 | |
| 295 | func (a *Agent) planVisibleCompression(snap explicitCompressionSnapshot, direction string, anchorIndex int, preview string) (visibleCompressionPlan, bool) { |
| 296 | sourceTokens := a.estimatedVisibleRequestTokens(snap.visible) |
| 297 | plan := visibleCompressionPlan{result: tool.CompressResult{ |
| 298 | Status: "noop", |
| 299 | Direction: direction, |
| 300 | Anchor: preview, |
| 301 | SourceTokens: sourceTokens, |
| 302 | ProjectionTokens: sourceTokens, |
| 303 | }} |
| 304 | if anchorIndex < 0 || anchorIndex >= len(snap.visible) { |
| 305 | plan.result.Reason = "anchor is no longer present in the model context" |
| 306 | return plan, false |
| 307 | } |
| 308 | head := 0 |
| 309 | if len(snap.visible) > 0 && snap.visible[0].Role == provider.RoleSystem { |
| 310 | head = 1 |
| 311 | } |
| 312 | completedEnd := len(snap.visible) |
| 313 | if active := a.activeTurnStart(snap.visible); active >= 0 { |
| 314 | completedEnd = active |
| 315 | } |
| 316 | start, end := head, anchorIndex |
| 317 | if direction == "after" { |
| 318 | start, end = anchorIndex, completedEnd |
| 319 | } |
| 320 | if start < head { |
| 321 | start = head |
| 322 | } |
| 323 | if end > completedEnd { |
| 324 | end = completedEnd |
| 325 | } |
| 326 | if start >= end { |
| 327 | plan.result.Reason = "selected range is empty" |
| 328 | return plan, false |
| 329 | } |
| 330 | |
| 331 | plan.foldMask = make([]bool, len(snap.visible)) |
| 332 | plan.dropMask = make([]bool, len(snap.visible)) |
| 333 | plan.firstFold = len(snap.visible) |
| 334 | latestContext := latestSessionContextIndex(snap.visible) |
| 335 | for i, msg := range snap.visible { |
| 336 | selected := i >= start && i < end |
| 337 | mergeSummary := i < completedEnd && isCompactionSummary(msg) |
| 338 | if isSessionContextMessage(msg) { |
| 339 | // Context never enters the summarizer. Once an older snapshot falls |
| 340 | // inside the explicitly compressed range, remove it from the |
| 341 | // projection; the latest valid snapshot remains byte-identical. |
| 342 | plan.dropMask[i] = selected && i != latestContext |
| 343 | continue |
| 344 | } |
| 345 | if msg.Role == provider.RoleSystem || i < head || (!selected && !mergeSummary) { |
| 346 | continue |
| 347 | } |
| 348 | plan.foldMask[i] = true |
| 349 | plan.fold = append(plan.fold, msg) |
| 350 | if i < plan.firstFold { |
| 351 | plan.firstFold = i |
| 352 | } |
| 353 | } |
| 354 | if len(plan.fold) == 0 { |
| 355 | plan.result.Reason = "selected range has no model-visible messages" |
| 356 | return plan, false |
| 357 | } |
| 358 | return plan, true |
| 359 | } |
| 360 | |
| 361 | func (a *Agent) prepareVisibleCompression(ctx context.Context, trigger string, fold []provider.Message, instructions, inputMode string) (preparedVisibleCompression, string, error) { |
| 362 | if a.svc.hooks != nil { |
| 363 | if hookInstructions := a.svc.hooks.PreCompact(ctx, trigger); hookInstructions != "" { |
| 364 | if instructions != "" { |
| 365 | instructions += "\n" |
| 366 | } |
| 367 | instructions += hookInstructions |
| 368 | } |
| 369 | } |
| 370 | filteredFold, removedPinned := withoutPinnedContextRevisions(fold) |
| 371 | if len(filteredFold) == 0 { |
| 372 | return preparedVisibleCompression{}, "selected range contains no summarizable messages", nil |
| 373 | } |
| 374 | if removedPinned { |
| 375 | inputMode = SummaryInputNonPrefix |
| 376 | } |
| 377 | originalHash := providerVisibleFingerprint(modelInputMessages(filteredFold)) |
| 378 | preparedFold, preparedInstructions, err := a.interceptCompactionPrepare(ctx, filteredFold, instructions) |
| 379 | if err != nil { |
| 380 | return preparedVisibleCompression{}, "", err |
| 381 | } |
| 382 | preparedFold = modelInputMessages(preparedFold) |
| 383 | if len(preparedFold) == 0 { |
| 384 | return preparedVisibleCompression{}, "compaction hook removed the selected range", nil |
| 385 | } |
| 386 | if !removedPinned && providerVisibleFingerprint(modelInputMessages(preparedFold)) != originalHash { |
| 387 | inputMode = SummaryInputExtensionRewritten |
| 388 | } |
| 389 | return preparedVisibleCompression{fold: preparedFold, instructions: preparedInstructions, inputMode: inputMode}, "", nil |
| 390 | } |
| 391 | |
| 392 | func buildVisibleCompressionProjection(visible []provider.Message, plan visibleCompressionPlan, summary string) []provider.Message { |
| 393 | projection := make([]provider.Message, 0, len(visible)-len(plan.fold)+1) |
| 394 | for i, msg := range visible { |
| 395 | if i == plan.firstFold { |
| 396 | projection = append(projection, formatSummaryMessage(summary)) |
| 397 | } |
| 398 | if !plan.foldMask[i] && (len(plan.dropMask) <= i || !plan.dropMask[i]) { |
| 399 | projection = append(projection, msg) |
| 400 | } |
| 401 | } |
| 402 | return projectionMessagesPreservingPinnedContext(projection) |
| 403 | } |
| 404 | |
| 405 | func compactionTelemetryFromSummary(trigger, cacheState string, sourceTokens int, res foldSummary) CompactionTelemetry { |
| 406 | tele := CompactionTelemetry{ |
| 407 | Trigger: trigger, CacheState: cacheState, Mode: res.Mode, |
| 408 | SourceTokens: sourceTokens, |
| 409 | ProviderRequestID: res.RequestID, |
| 410 | FoldTokens: res.FoldTokens, |
| 411 | Spans: res.Spans, |
| 412 | SummaryInputMode: res.InputMode, |
| 413 | } |
| 414 | if tele.Spans <= 0 { |
| 415 | tele.Spans = 1 |
| 416 | } |
| 417 | usage := res.Usage |
| 418 | if usage == nil { |
| 419 | return tele |
| 420 | } |
| 421 | tele.InputTokens = usage.PromptTokens |
| 422 | tele.OutputTokens = usage.CompletionTokens |
| 423 | tele.CacheHitTokens = usage.CacheHitTokens |
| 424 | tele.CacheMissTokens = usage.CacheMissTokens |
| 425 | tele.CacheWriteTokens = usage.CacheWriteTokens |
| 426 | tele.RequestCount = usage.RequestCount |
| 427 | if tele.RequestCount <= 0 { |
| 428 | tele.RequestCount = 1 |
| 429 | } |
| 430 | return tele |
| 431 | } |
| 432 | |
| 433 | // foldSummaryWithChunkedFallback retries summary size failures through the |
| 434 | // resilient fragment/tree-reduce path used for over-length sessions. |
| 435 | func (a *Agent) foldSummaryWithChunkedFallback(ctx context.Context, trigger string, fold []provider.Message, instructions string, sourceTokens int, inputMode string) (foldSummary, CompactionTelemetry, error) { |
| 436 | res, tele, err := a.foldSummaryWithTelemetry(ctx, trigger, fold, instructions, sourceTokens, inputMode) |
| 437 | if err == nil || !chunkedFallbackApplies(err, inputMode) { |
| 438 | return res, tele, err |
| 439 | } |
| 440 | chunked, chunkedErr := a.chunkedFoldSummary(ctx, fold, instructions, nil) |
| 441 | chunked.Usage = mergeSamplingUsage(res.Usage, chunked.Usage) |
| 442 | chunked.Spans += res.Spans |
| 443 | if chunked.FoldTokens <= 0 { |
| 444 | chunked.FoldTokens = res.FoldTokens |
| 445 | } |
| 446 | if chunked.RequestID == "" { |
| 447 | chunked.RequestID = res.RequestID |
| 448 | } |
| 449 | if chunkedErr != nil { |
| 450 | tele = compactionTelemetryFromSummary(trigger, a.CacheState(), sourceTokens, chunked) |
| 451 | tele.Error = fmt.Sprintf("%v (chunked fallback: %v)", err, chunkedErr) |
| 452 | return chunked, tele, chunkedErr |
| 453 | } |
| 454 | return chunked, compactionTelemetryFromSummary(trigger, a.CacheState(), sourceTokens, chunked), nil |
| 455 | } |
| 456 | |
| 457 | // chunkedFallbackApplies reports a size failure the fragment path can fix. A |
| 458 | // provider overflow qualifies only once the transcript form has failed too; |
| 459 | // before that a re-planned replay is one request instead of many. |
| 460 | func chunkedFallbackApplies(err error, inputMode string) bool { |
| 461 | if provider.AsContextLimitError(err) != nil { |
| 462 | return inputMode == SummaryInputSlim |
| 463 | } |
| 464 | return summarySizeFailure(err) |
| 465 | } |
| 466 | |
| 467 | // compact writes a context projection; trigger stays "auto"/"manual" for UI cards. |
| 468 | func (a *Agent) summarizeFold(ctx context.Context, trigger string, fold []provider.Message, instructions string, sourceTokens int, inputMode string, req foldRequest) (foldSummary, CompactionTelemetry, error) { |
| 469 | if req.allowChunked { |
| 470 | return a.foldSummaryWithChunkedFallback(ctx, trigger, fold, instructions, sourceTokens, inputMode) |
| 471 | } |
| 472 | return a.foldSummaryWithTelemetry(ctx, trigger, fold, instructions, sourceTokens, inputMode) |
| 473 | } |
| 474 | |
| 475 | func (a *Agent) compactToProjectionLocked(ctx context.Context, trigger, instructions string, req foldRequest) (CompactionOutcome, error) { |
| 476 | activeTurn := a.activeTurnCreatedAt.Load() |
| 477 | canonical, transcriptVersion := a.sess.conversation.snapshotMessagesVersion() |
| 478 | a.sess.compactionMu.Lock() |
| 479 | stateSnapshot := a.sess.compactionState |
| 480 | startProjectionVersion := a.sess.compactionState.Projection.ProjectionVersion |
| 481 | startGeneration := a.sess.compactionState.Generation |
| 482 | a.sess.compactionMu.Unlock() |
| 483 | msgs, onProjection := a.visibleInputForFold(stateSnapshot, canonical, transcriptVersion) |
| 484 | viewInputHash := providerVisibleFingerprint(modelInputMessages(msgs)) |
| 485 | head, start, ok := a.planFoldRegion(msgs, req.force, req.mustFree) |
| 486 | if !ok { |
| 487 | return CompactionNoop, nil |
| 488 | } |
| 489 | latestContext := latestSessionContextIndex(msgs) |
| 490 | _, preliminaryFold, _ := a.partitionFoldForProjectionAt(msgs[head:start], head, latestContext) |
| 491 | if len(preliminaryFold) == 0 || (!req.force && !foldEconomics(preliminaryFold)) { |
| 492 | return CompactionNoop, nil |
| 493 | } |
| 494 | fixedPrefixTokens := a.estimatedVisibleRequestTokens(msgs[:head]) |
| 495 | if a.contextWindow > 0 && fixedPrefixTokens >= a.compactTrigger() { |
| 496 | return CompactionNoop, fmt.Errorf("%w: fixed prefix (%d tokens) already exceeds trigger (%d)", errCheckpointRejected, fixedPrefixTokens, a.compactTrigger()) |
| 497 | } |
| 498 | |
| 499 | a.svc.sink.Emit(event.Event{Kind: event.CompactionStarted, Compaction: event.Compaction{Trigger: trigger}}) |
| 500 | if a.svc.hooks != nil { |
| 501 | if hookInstr := a.svc.hooks.PreCompact(ctx, trigger); hookInstr != "" { |
| 502 | if instructions != "" { |
| 503 | instructions += "\n" |
| 504 | } |
| 505 | instructions += hookInstr |
| 506 | } |
| 507 | } |
| 508 | // Cap every automatic summary input (#9572), including pressure folds after |
| 509 | // projection invalidation. mustFree also covers the over-ceiling manual rescue |
| 510 | // merged in #9474; ordinary manual compaction keeps its requested range. |
| 511 | if req.mustFree || trigger != CompactionTriggerManual { |
| 512 | start = a.maximumSafeSummaryPrefixEnd(msgs, head, start, instructions) |
| 513 | if start <= head { |
| 514 | a.emitCompactionAborted(trigger) |
| 515 | return CompactionNoop, fmt.Errorf("%w: no balanced prefix leaves enough room for a summary response", errCheckpointRejected) |
| 516 | } |
| 517 | } |
| 518 | |
| 519 | covered, bodySuffix := projectionCoverageForFold(stateSnapshot, msgs, start, onProjection) |
| 520 | regionHadPinnedRevision := containsPinnedContextRevision(msgs[head:start]) |
| 521 | kept, fold, retention := a.partitionFoldForProjectionAt(msgs[head:start], head, latestContext) |
| 522 | if len(fold) == 0 { |
| 523 | a.emitCompactionAborted(trigger) |
| 524 | return CompactionNoop, nil |
| 525 | } |
| 526 | originalFoldHash := providerVisibleFingerprint(modelInputMessages(fold)) |
| 527 | var err error |
| 528 | fold, instructions, err = a.interceptCompactionPrepare(ctx, fold, instructions) |
| 529 | if err != nil { |
| 530 | a.emitCompactionAborted(trigger) |
| 531 | return CompactionNoop, err |
| 532 | } |
| 533 | if len(fold) == 0 { |
| 534 | a.emitCompactionAborted(trigger) |
| 535 | return CompactionNoop, nil |
| 536 | } |
| 537 | if req.mustFree || trigger != CompactionTriggerManual { |
| 538 | if err := a.validateSafeSummaryRequest(fold, instructions, req.slim); err != nil { |
| 539 | a.emitCompactionAborted(trigger) |
| 540 | return CompactionNoop, err |
| 541 | } |
| 542 | } |
| 543 | |
| 544 | sourceTokens := a.estimatedVisibleRequestTokens(msgs) |
| 545 | inputMode := summaryInputModeFor(req, regionHadPinnedRevision, |
| 546 | providerVisibleFingerprint(modelInputMessages(fold)) != originalFoldHash) |
| 547 | res, tele, err := a.summarizeFold(ctx, trigger, fold, instructions, sourceTokens, inputMode, req) |
| 548 | if err != nil { |
| 549 | a.emitCompactionTelemetry(tele) |
| 550 | a.emitCompactionAborted(trigger) |
| 551 | return CompactionNoop, err |
| 552 | } |
| 553 | summary, err := a.interceptCompactionComplete(ctx, res.Text) |
| 554 | if err != nil { |
| 555 | tele.Error = err.Error() |
| 556 | a.emitCompactionTelemetry(tele) |
| 557 | a.emitCompactionAborted(trigger) |
| 558 | return CompactionNoop, err |
| 559 | } |
| 560 | |
| 561 | // The projection body freezes only prefix + digest + kept messages; the |
| 562 | // verbatim tail splices live from canonical[start:] so tail-side rewrites |
| 563 | // (rewind truncation, snips) stay visible without rebuilding the fold. |
| 564 | projMsgs := checkpointProjectionMessages(msgs, head, kept, summary) |
| 565 | if len(bodySuffix) > 0 { |
| 566 | projMsgs = append(projMsgs, projectionMessagesPreservingPinnedContext(bodySuffix)...) |
| 567 | } |
| 568 | tele.UserTurnsKept, tele.UserTurnsDropped = retention.Kept, retention.Dropped |
| 569 | projMsgs, spliced, projTokens, err := a.preparePinnedCheckpointCandidate(trigger, projMsgs, canonical, covered, sourceTokens, &tele) |
| 570 | if err != nil { |
| 571 | a.emitCompactionAborted(trigger) |
| 572 | return CompactionNoop, err |
| 573 | } |
| 574 | viewOutputHash := providerVisibleFingerprint(modelInputMessages(spliced)) |
| 575 | _, err = a.commitSummaryProjection(summaryProjectionCommit{ |
| 576 | canonical: canonical, fold: fold, projected: projMsgs, result: res, |
| 577 | transcriptVersion: transcriptVersion, projectionVersion: startProjectionVersion, |
| 578 | generation: startGeneration, activeTurn: activeTurn, trigger: trigger, |
| 579 | summary: summary, inputHash: viewInputHash, outputHash: viewOutputHash, |
| 580 | sourceTokens: sourceTokens, projectionTokens: projTokens, covered: covered, |
| 581 | }) |
| 582 | if err != nil { |
| 583 | a.emitCompactionAborted(trigger) |
| 584 | return CompactionNoop, err |
| 585 | } |
| 586 | a.svc.sink.Emit(event.Event{Kind: event.CompactionDone, Compaction: event.Compaction{ |
| 587 | Trigger: trigger, Messages: len(fold), Summary: summary, |
| 588 | }}) |
| 589 | return CompactionInstalled, nil |
| 590 | } |
| 591 | |
| 592 | func (a *Agent) preparePinnedCheckpointCandidate( |
| 593 | trigger string, |
| 594 | projection, canonical []provider.Message, |
| 595 | covered, sourceTokens int, |
| 596 | tele *CompactionTelemetry, |
| 597 | ) ([]provider.Message, []provider.Message, int, error) { |
| 598 | projection, pinnedCheckpoint, err := rebasePinnedContextProjection(projection, canonical, covered) |
| 599 | if err != nil { |
| 600 | return nil, nil, 0, err |
| 601 | } |
| 602 | spliced := append(append([]provider.Message(nil), projection...), canonical[covered:]...) |
| 603 | projectionTokens := a.estimatedVisibleRequestTokens(spliced) |
| 604 | tele.ProjectionTokens = projectionTokens |
| 605 | a.emitCompactionTelemetry(*tele) |
| 606 | if err := a.acceptCheckpointCandidate(trigger, sourceTokens, projectionTokens); err != nil { |
| 607 | if pinnedCheckpoint { |
| 608 | return nil, nil, 0, fmt.Errorf("pinned-context-too-large: checkpoint prevents compaction acceptance: %w", err) |
| 609 | } |
| 610 | return nil, nil, 0, err |
| 611 | } |
| 612 | return projection, spliced, projectionTokens, nil |
| 613 | } |
| 614 | |
| 615 | // projectionCoverageForFold maps a working-view boundary to canonical |
| 616 | // coverage. A suffix inside an existing frozen body remains in the new body |
| 617 | // because it has no corresponding canonical tail to splice from. |
| 618 | func projectionCoverageForFold(state CompactionState, msgs []provider.Message, start int, onProjection bool) (int, []provider.Message) { |
| 619 | if !onProjection { |
| 620 | return start, nil |
| 621 | } |
| 622 | body := len(state.Projection.Messages) |
| 623 | prior := state.Projection.CoveredCount |
| 624 | if start < body { |
| 625 | return prior, msgs[start:body] |
| 626 | } |
| 627 | return prior + (start - body), nil |
| 628 | } |
| 629 | |
| 630 | // visibleInputForFold prefers the prior projection + new history over full |
| 631 | // canonical. The second return reports whether the projection was used, so |
| 632 | // fold boundaries can be translated back to canonical indices. |
| 633 | func (a *Agent) visibleInputForFold(state CompactionState, canonical []provider.Message, transcriptVersion uint64) ([]provider.Message, bool) { |
| 634 | if projectionValid(state, canonical, a.currentPromptCacheKey()) { |
| 635 | if projected := modelVisibleFromProjection(state.Projection, canonical); len(projected) > 0 { |
| 636 | return projected, true |
| 637 | } |
| 638 | } |
| 639 | return canonical, false |
| 640 | } |
| 641 | |
| 642 | func checkpointProjectionMessages(msgs []provider.Message, head int, kept []provider.Message, summary string) []provider.Message { |
| 643 | projMsgs := make([]provider.Message, 0, head+1+len(kept)) |
| 644 | projMsgs = append(projMsgs, msgs[:head]...) |
| 645 | projMsgs = append(projMsgs, kept...) |
| 646 | projMsgs = append(projMsgs, formatSummaryMessage(summary)) |
| 647 | return provider.ProjectionMessages(projMsgs) |
| 648 | } |
| 649 | |
| 650 | // acceptCheckpointCandidate requires real savings and, for automatic |
| 651 | // maintenance, a result below the physical input ceiling. |
| 652 | func (a *Agent) acceptCheckpointCandidate(trigger string, sourceTokens, candidateTokens int) error { |
| 653 | if candidateTokens >= sourceTokens { |
| 654 | return fmt.Errorf("%w: candidate would not reduce tokens (%d >= %d)", errCheckpointRejected, candidateTokens, sourceTokens) |
| 655 | } |
| 656 | hard := a.hardInputCeiling() |
| 657 | if trigger != CompactionTriggerManual && hard > 0 && candidateTokens >= hard { |
| 658 | return fmt.Errorf("%w: candidate %d still at or above physical ceiling %d", errCheckpointRejected, candidateTokens, hard) |
| 659 | } |
| 660 | return nil |
| 661 | } |
| 662 | |
| 663 | // planFoldRegion returns [head:start] to fold; force shrinks the recent tail. |
| 664 | // splitActive lets an overflow rescue fold the active turn's older completed |
| 665 | // rounds as well; otherwise the active turn stays verbatim. |
| 666 | func (a *Agent) planFoldRegion(msgs []provider.Message, force, splitActive bool) (head, start int, ok bool) { |
| 667 | head, start, ok = a.planCompaction(msgs, minCompactMessages, force) |
| 668 | if !ok { |
| 669 | head, start, ok = a.planCompaction(msgs, 1, force) |
| 670 | } |
| 671 | if !ok { |
| 672 | return head, start, false |
| 673 | } |
| 674 | if active := a.activeTurnStart(msgs); active >= head && active < start { |
| 675 | if splitActive { |
| 676 | start = activeTurnFoldBoundary(msgs, active, start) |
| 677 | } else { |
| 678 | start = active |
| 679 | } |
| 680 | } |
| 681 | return head, start, start > head |
| 682 | } |
| 683 | |
| 684 | type userTurnRetention struct { |
| 685 | Kept int |
| 686 | Dropped int |
| 687 | } |
| 688 | |
| 689 | func (a *Agent) partitionFoldForProjection(region []provider.Message) (kept, fold []provider.Message, retention userTurnRetention) { |
| 690 | return a.partitionFoldForProjectionAt(region, 0, latestSessionContextIndex(region)) |
| 691 | } |
| 692 | |
| 693 | func (a *Agent) partitionFoldForProjectionAt(region []provider.Message, offset, latestContext int) (kept, fold []provider.Message, retention userTurnRetention) { |
| 694 | for i, m := range region { |
| 695 | if m.LocalOnly || IsPinnedContextRevision(m) { |
| 696 | continue |
| 697 | } |
| 698 | if isSessionContextMessage(m) { |
| 699 | if offset+i == latestContext { |
| 700 | kept = append(kept, m) |
| 701 | } |
| 702 | continue |
| 703 | } |
| 704 | fold = append(fold, m) |
| 705 | if IsUserAuthoredTurnMessage(m) { |
| 706 | retention.Dropped++ |
| 707 | } |
| 708 | } |
| 709 | return kept, fold, retention |
| 710 | } |
| 711 | |
| 712 | func latestSessionContextIndex(messages []provider.Message) int { |
| 713 | for i := range slices.Backward(messages) { |
| 714 | if isSessionContextMessage(messages[i]) { |
| 715 | return i |
| 716 | } |
| 717 | } |
| 718 | return -1 |
| 719 | } |
| 720 | |
| 721 | // runCompactionSummary uses the single local summarizer path for every provider. |
| 722 | func (a *Agent) runCompactionSummary(ctx context.Context, fold []provider.Message, instructions string) (summary, mode string, usage *provider.Usage, providerReqID string, err error) { |
| 723 | summary, usage, err = a.summarizeOnce(ctx, fold, instructions) |
| 724 | if err != nil { |
| 725 | return "", CompactionModeSummarized, usage, "", err |
| 726 | } |
| 727 | return summary, CompactionModeSummarized, usage, "", nil |
| 728 | } |
| 729 |