add Automatically compacted context

README.md

@@ -156,6 +156,7 @@ Shell 工具默认启用 Risk Gate。检测到破坏性命令时，默认阻断
 
 - `memory_search`：增加结构化索引（倒排索引 + 缓存），优先走索引检索。
 - 记忆分层：支持 `profile / project / procedures / recent notes`。
+- 自动上下文压缩（Automatically Compacted Context）：会话过长时自动生成摘要并裁剪历史，降低 token 开销与卡顿风险。
 
 ```json
 "memory": {
@@ -169,6 +170,30 @@ Shell 工具默认启用 Risk Gate。检测到破坏性命令时，默认阻断
 }
 ```
 
+上下文自动压缩配置：
+
+```json
+"agents": {
+  "defaults": {
+    "context_compaction": {
+      "enabled": true,
+      "trigger_messages": 60,
+      "keep_recent_messages": 20,
+      "max_summary_chars": 6000,
+      "max_transcript_chars": 20000
+    }
+  }
+}
+```
+
+也可以热更新：
+
+```bash
+clawgo config set agents.defaults.context_compaction.enabled true
+clawgo config set agents.defaults.context_compaction.trigger_messages 80
+clawgo config set agents.defaults.context_compaction.keep_recent_messages 24
+```
+
 ## 🗺️ Repo-Map 与原子技能
 
 - `repo_map`：生成并查询代码全景地图，先定位目标文件再精读。

pkg/agent/loop.go

@@ -44,6 +44,7 @@ type AgentLoop struct {
 	tools          *tools.ToolRegistry
 	orchestrator   *tools.Orchestrator
 	running        atomic.Bool
+	compactionCfg  config.ContextCompactionConfig
 }
 
 func NewAgentLoop(cfg *config.Config, msgBus *bus.MessageBus, provider providers.LLMProvider, cs *cron.CronService) *AgentLoop {
@@ -125,6 +126,7 @@ func NewAgentLoop(cfg *config.Config, msgBus *bus.MessageBus, provider providers
 		contextBuilder: NewContextBuilder(workspace, cfg.Memory, func() []string { return toolsRegistry.GetSummaries() }),
 		tools:          toolsRegistry,
 		orchestrator:   orchestrator,
+		compactionCfg:  cfg.Agents.Defaults.ContextCompaction,
 	}
 
 	// 注入递归运行逻辑，使 subagent 具备 full tool-calling 能力
@@ -259,7 +261,7 @@ func (al *AgentLoop) processMessage(ctx context.Context, msg bus.InboundMessage)
 		Content: userContent,
 	})
 
-	if err := al.sessions.Save(al.sessions.GetOrCreate(msg.SessionKey)); err != nil {
+	if err := al.persistSessionWithCompaction(ctx, msg.SessionKey); err != nil {
 		logger.WarnCF("agent", "Failed to save session metadata", map[string]interface{}{
 			"session_key":     msg.SessionKey,
 			logger.FieldError: err.Error(),
@@ -348,7 +350,7 @@ func (al *AgentLoop) processSystemMessage(ctx context.Context, msg bus.InboundMe
 		Content: finalContent,
 	})
 
-	if err := al.sessions.Save(al.sessions.GetOrCreate(sessionKey)); err != nil {
+	if err := al.persistSessionWithCompaction(ctx, sessionKey); err != nil {
 		logger.WarnCF("agent", "Failed to save session metadata", map[string]interface{}{
 			"session_key":     sessionKey,
 			logger.FieldError: err.Error(),
@@ -718,6 +720,124 @@ func formatToolsForLog(tools []providers.ToolDefinition) string {
 	return result
 }
 
+func (al *AgentLoop) persistSessionWithCompaction(ctx context.Context, sessionKey string) error {
+	if err := al.maybeCompactContext(ctx, sessionKey); err != nil {
+		logger.WarnCF("agent", "Context compaction skipped due to error", map[string]interface{}{
+			"session_key":     sessionKey,
+			logger.FieldError: err.Error(),
+		})
+	}
+	return al.sessions.Save(al.sessions.GetOrCreate(sessionKey))
+}
+
+func (al *AgentLoop) maybeCompactContext(ctx context.Context, sessionKey string) error {
+	cfg := al.compactionCfg
+	if !cfg.Enabled {
+		return nil
+	}
+
+	messageCount := al.sessions.MessageCount(sessionKey)
+	if messageCount < cfg.TriggerMessages {
+		return nil
+	}
+
+	history := al.sessions.GetHistory(sessionKey)
+	if len(history) < cfg.TriggerMessages {
+		return nil
+	}
+	if cfg.KeepRecentMessages >= len(history) {
+		return nil
+	}
+
+	summary := al.sessions.GetSummary(sessionKey)
+	compactUntil := len(history) - cfg.KeepRecentMessages
+	compactCtx, cancel := context.WithTimeout(ctx, 25*time.Second)
+	defer cancel()
+	newSummary, err := al.buildCompactedSummary(compactCtx, summary, history[:compactUntil], cfg.MaxTranscriptChars)
+	if err != nil {
+		return err
+	}
+	newSummary = strings.TrimSpace(newSummary)
+	if newSummary == "" {
+		return nil
+	}
+	if len(newSummary) > cfg.MaxSummaryChars {
+		newSummary = truncateString(newSummary, cfg.MaxSummaryChars)
+	}
+
+	before, after, err := al.sessions.CompactHistory(sessionKey, newSummary, cfg.KeepRecentMessages)
+	if err != nil {
+		return err
+	}
+
+	logger.InfoCF("agent", "Context compacted automatically", map[string]interface{}{
+		"session_key":      sessionKey,
+		"before_messages":  before,
+		"after_messages":   after,
+		"kept_recent":      cfg.KeepRecentMessages,
+		"summary_chars":    len(newSummary),
+		"trigger_messages": cfg.TriggerMessages,
+	})
+	return nil
+}
+
+func (al *AgentLoop) buildCompactedSummary(
+	ctx context.Context,
+	existingSummary string,
+	messages []providers.Message,
+	maxTranscriptChars int,
+) (string, error) {
+	transcript := formatCompactionTranscript(messages, maxTranscriptChars)
+	if strings.TrimSpace(transcript) == "" {
+		return strings.TrimSpace(existingSummary), nil
+	}
+
+	systemPrompt := "You are a conversation compactor. Merge prior summary and transcript into a concise, factual memory for future turns. Keep user preferences, constraints, decisions, unresolved tasks, and key technical context. Do not include speculative content."
+	userPrompt := fmt.Sprintf("Existing summary:\n%s\n\nTranscript to compact:\n%s\n\nReturn a compact markdown summary with sections: Key Facts, Decisions, Open Items, Next Steps.",
+		strings.TrimSpace(existingSummary), transcript)
+
+	resp, err := al.callLLMWithModelFallback(ctx, []providers.Message{
+		{Role: "system", Content: systemPrompt},
+		{Role: "user", Content: userPrompt},
+	}, nil, map[string]interface{}{
+		"max_tokens":  1200,
+		"temperature": 0.2,
+	})
+	if err != nil {
+		return "", err
+	}
+	return resp.Content, nil
+}
+
+func formatCompactionTranscript(messages []providers.Message, maxChars int) string {
+	if maxChars <= 0 || len(messages) == 0 {
+		return ""
+	}
+
+	var sb strings.Builder
+	used := 0
+	for _, m := range messages {
+		role := strings.TrimSpace(m.Role)
+		if role == "" {
+			role = "unknown"
+		}
+		line := fmt.Sprintf("[%s] %s\n", role, strings.TrimSpace(m.Content))
+		if len(line) > 1200 {
+			line = truncateString(line, 1200) + "\n"
+		}
+		if used+len(line) > maxChars {
+			remain := maxChars - used
+			if remain > 16 {
+				sb.WriteString(truncateString(line, remain))
+			}
+			break
+		}
+		sb.WriteString(line)
+		used += len(line)
+	}
+	return strings.TrimSpace(sb.String())
+}
+
 func (al *AgentLoop) handleSlashCommand(content string) (bool, string, error) {
 	text := strings.TrimSpace(content)
 	if !strings.HasPrefix(text, "/") {

pkg/config/config.go

@@ -27,12 +27,21 @@ type AgentsConfig struct {
 }
 
 type AgentDefaults struct {
-	Workspace         string   `json:"workspace" env:"CLAWGO_AGENTS_DEFAULTS_WORKSPACE"`
+	Workspace         string                  `json:"workspace" env:"CLAWGO_AGENTS_DEFAULTS_WORKSPACE"`
-	Model             string   `json:"model" env:"CLAWGO_AGENTS_DEFAULTS_MODEL"`
+	Model             string                  `json:"model" env:"CLAWGO_AGENTS_DEFAULTS_MODEL"`
-	ModelFallbacks    []string `json:"model_fallbacks" env:"CLAWGO_AGENTS_DEFAULTS_MODEL_FALLBACKS"`
+	ModelFallbacks    []string                `json:"model_fallbacks" env:"CLAWGO_AGENTS_DEFAULTS_MODEL_FALLBACKS"`
-	MaxTokens         int      `json:"max_tokens" env:"CLAWGO_AGENTS_DEFAULTS_MAX_TOKENS"`
+	MaxTokens         int                     `json:"max_tokens" env:"CLAWGO_AGENTS_DEFAULTS_MAX_TOKENS"`
-	Temperature       float64  `json:"temperature" env:"CLAWGO_AGENTS_DEFAULTS_TEMPERATURE"`
+	Temperature       float64                 `json:"temperature" env:"CLAWGO_AGENTS_DEFAULTS_TEMPERATURE"`
-	MaxToolIterations int      `json:"max_tool_iterations" env:"CLAWGO_AGENTS_DEFAULTS_MAX_TOOL_ITERATIONS"`
+	MaxToolIterations int                     `json:"max_tool_iterations" env:"CLAWGO_AGENTS_DEFAULTS_MAX_TOOL_ITERATIONS"`
+	ContextCompaction ContextCompactionConfig `json:"context_compaction"`
+}
+
+type ContextCompactionConfig struct {
+	Enabled            bool `json:"enabled" env:"CLAWGO_AGENTS_DEFAULTS_CONTEXT_COMPACTION_ENABLED"`
+	TriggerMessages    int  `json:"trigger_messages" env:"CLAWGO_AGENTS_DEFAULTS_CONTEXT_COMPACTION_TRIGGER_MESSAGES"`
+	KeepRecentMessages int  `json:"keep_recent_messages" env:"CLAWGO_AGENTS_DEFAULTS_CONTEXT_COMPACTION_KEEP_RECENT_MESSAGES"`
+	MaxSummaryChars    int  `json:"max_summary_chars" env:"CLAWGO_AGENTS_DEFAULTS_CONTEXT_COMPACTION_MAX_SUMMARY_CHARS"`
+	MaxTranscriptChars int  `json:"max_transcript_chars" env:"CLAWGO_AGENTS_DEFAULTS_CONTEXT_COMPACTION_MAX_TRANSCRIPT_CHARS"`
 }
 
 type ChannelsConfig struct {
@@ -213,6 +222,13 @@ func DefaultConfig() *Config {
 				MaxTokens:         8192,
 				Temperature:       0.7,
 				MaxToolIterations: 20,
+				ContextCompaction: ContextCompactionConfig{
+					Enabled:            true,
+					TriggerMessages:    60,
+					KeepRecentMessages: 20,
+					MaxSummaryChars:    6000,
+					MaxTranscriptChars: 20000,
+				},
 			},
 		},
 		Channels: ChannelsConfig{

pkg/config/validate.go

@@ -17,6 +17,24 @@ func Validate(cfg *Config) []error {
 	if cfg.Agents.Defaults.MaxToolIterations <= 0 {
 		errs = append(errs, fmt.Errorf("agents.defaults.max_tool_iterations must be > 0"))
 	}
+	if cfg.Agents.Defaults.ContextCompaction.Enabled {
+		cc := cfg.Agents.Defaults.ContextCompaction
+		if cc.TriggerMessages <= 0 {
+			errs = append(errs, fmt.Errorf("agents.defaults.context_compaction.trigger_messages must be > 0 when enabled=true"))
+		}
+		if cc.KeepRecentMessages <= 0 {
+			errs = append(errs, fmt.Errorf("agents.defaults.context_compaction.keep_recent_messages must be > 0 when enabled=true"))
+		}
+		if cc.TriggerMessages > 0 && cc.KeepRecentMessages >= cc.TriggerMessages {
+			errs = append(errs, fmt.Errorf("agents.defaults.context_compaction.keep_recent_messages must be < trigger_messages"))
+		}
+		if cc.MaxSummaryChars <= 0 {
+			errs = append(errs, fmt.Errorf("agents.defaults.context_compaction.max_summary_chars must be > 0 when enabled=true"))
+		}
+		if cc.MaxTranscriptChars <= 0 {
+			errs = append(errs, fmt.Errorf("agents.defaults.context_compaction.max_transcript_chars must be > 0 when enabled=true"))
+		}
+	}
 
 	if cfg.Providers.Proxy.APIBase == "" {
 		errs = append(errs, fmt.Errorf("providers.proxy.api_base is required"))

pkg/session/manager.go

@@ -3,6 +3,7 @@ package session
 import (
 	"bufio"
 	"encoding/json"
+	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
@@ -120,6 +121,35 @@ func (sm *SessionManager) appendMessage(sessionKey string, msg providers.Message
 	return err
 }
 
+func (sm *SessionManager) rewriteHistory(sessionKey string, messages []providers.Message) error {
+	if sm.storage == "" {
+		return nil
+	}
+
+	sessionPath := filepath.Join(sm.storage, sessionKey+".jsonl")
+	tmpPath := sessionPath + ".tmp"
+
+	f, err := os.OpenFile(tmpPath, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0644)
+	if err != nil {
+		return err
+	}
+
+	enc := json.NewEncoder(f)
+	for _, msg := range messages {
+		if err := enc.Encode(msg); err != nil {
+			_ = f.Close()
+			_ = os.Remove(tmpPath)
+			return err
+		}
+	}
+
+	if err := f.Close(); err != nil {
+		_ = os.Remove(tmpPath)
+		return err
+	}
+	return os.Rename(tmpPath, sessionPath)
+}
+
 func (sm *SessionManager) GetHistory(key string) []providers.Message {
 	sm.mu.RLock()
 	session, ok := sm.sessions[key]
@@ -186,6 +216,49 @@ func (sm *SessionManager) TruncateHistory(key string, keepLast int) {
 	session.Updated = time.Now()
 }
 
+func (sm *SessionManager) MessageCount(key string) int {
+	sm.mu.RLock()
+	session, ok := sm.sessions[key]
+	sm.mu.RUnlock()
+	if !ok {
+		return 0
+	}
+
+	session.mu.RLock()
+	defer session.mu.RUnlock()
+	return len(session.Messages)
+}
+
+func (sm *SessionManager) CompactHistory(key, summary string, keepLast int) (int, int, error) {
+	sm.mu.RLock()
+	session, ok := sm.sessions[key]
+	sm.mu.RUnlock()
+	if !ok {
+		return 0, 0, fmt.Errorf("session not found: %s", key)
+	}
+
+	if keepLast < 0 {
+		keepLast = 0
+	}
+
+	session.mu.Lock()
+	before := len(session.Messages)
+	if keepLast < before {
+		session.Messages = session.Messages[before-keepLast:]
+	}
+	session.Summary = summary
+	session.Updated = time.Now()
+	after := len(session.Messages)
+	msgs := make([]providers.Message, after)
+	copy(msgs, session.Messages)
+	session.mu.Unlock()
+
+	if err := sm.rewriteHistory(key, msgs); err != nil {
+		return before, after, err
+	}
+	return before, after, nil
+}
+
 func (sm *SessionManager) Save(session *Session) error {
 	// 现已通过 AddMessageFull 实时增量持久化
 	// 这里保留 Save 方法用于更新 Summary 等元数据