feat: support opencode

Author: 35C4n0r

README.md

@@ -65,7 +65,7 @@ agentapi server -- goose
 ```
 
 > [!NOTE]
-> When using Codex, Gemini, Amp or CursorCLI, always specify the agent type explicitly (eg: `agentapi server --type=codex -- codex`), or message formatting may break.
+> When using Codex, Opencode, Gemini, Amp or CursorCLI, always specify the agent type explicitly (eg: `agentapi server --type=codex -- codex`), or message formatting may break.
 
 An OpenAPI schema is available in [openapi.json](openapi.json).
 

cmd/server/server.go

@@ -32,6 +32,7 @@ const (
 	AgentTypeCursorAgent AgentType = msgfmt.AgentTypeCursorAgent
 	AgentTypeCursor      AgentType = msgfmt.AgentTypeCursor
 	AgentTypeAuggie      AgentType = msgfmt.AgentTypeAuggie
+	AgentTypeOpencode    AgentType = msgfmt.AgentTypeOpencode
 	AgentTypeCustom      AgentType = msgfmt.AgentTypeCustom
 )
 
@@ -46,6 +47,7 @@ var agentTypeMap = map[AgentType]bool{
 	AgentTypeCursorAgent: true,
 	AgentTypeCursor:      true,
 	AgentTypeAuggie:      true,
+	AgentTypeOpencode:    true,
 	AgentTypeCustom:      true,
 }
 

cmd/server/server_test.go

@@ -57,6 +57,11 @@ func TestParseAgentType(t *testing.T) {
 			agentTypeVar: "",
 			want:         AgentTypeCursor,
 		},
+		{
+			firstArg:     "opencode",
+			agentTypeVar: "",
+			want:         AgentTypeOpencode,
+		},
 		{
 			firstArg:     "auggie",
 			agentTypeVar: "",
@@ -97,6 +102,11 @@ func TestParseAgentType(t *testing.T) {
 			agentTypeVar: "gemini",
 			want:         AgentTypeGemini,
 		},
+		{
+			firstArg:     "claude",
+			agentTypeVar: "opencode",
+			want:         AgentTypeOpencode,
+		},
 		{
 			firstArg:     "claude",
 			agentTypeVar: "cursor-agent",

lib/httpapi/server.go

@@ -196,7 +196,8 @@ func NewServer(ctx context.Context, config ServerConfig) (*Server, error) {
 		return mf.FormatAgentMessage(config.AgentType, message, userInput)
 	}
 	conversation := st.NewConversation(ctx, st.ConversationConfig{
-		AgentIO: config.Process,
+		AgentType: config.AgentType,
+		AgentIO:   config.Process,
 		GetTime: func() time.Time {
 			return time.Now()
 		},

lib/msgfmt/message_box.go

@@ -60,3 +60,21 @@ func removeCodexInputBox(msg string) string {
 	}
 	return strings.Join(lines, "\n")
 }
+
+func removeOpencodeMessageBox(msg string) string {
+	lines := strings.Split(msg, "\n")
+	// Check the last 3 lines for
+	//
+	//  ┃                                                                      ┃
+	//  ┃ >                                                                    ┃
+	//  ┃                                                                      ┃
+	// We only check for the first ┃ and then an empty line above it as sometimes the full block load within a snapshot this leads to ..
+	for i := len(lines) - 1; i >= 1; i-- {
+		if strings.TrimSpace(lines[i-1]) == "" &&
+			strings.ReplaceAll(lines[i], " ", "") == "┃┃" {
+			lines = lines[:i-1]
+			break
+		}
+	}
+	return strings.Join(lines, "\n")
+}

lib/msgfmt/msgfmt.go

@@ -196,6 +196,13 @@ func RemoveUserInput(msgRaw string, userInputRaw string, agentType AgentType) st
 		if idx, found := skipTrailingInputBoxLine(msgLines, lastUserInputLineIdx, "┘", "└"); found {
 			lastUserInputLineIdx = idx
 		}
+	} else if agentType == AgentTypeOpencode {
+		// skip +2 lines after the input
+		//   ┃  jkmr (08:46 PM)                                                     ┃
+		//   ┃                                                                      ┃
+		if lastUserInputLineIdx+2 < len(msgLines) {
+			lastUserInputLineIdx += 2
+		}
 	}
 
 	return strings.Join(msgLines[lastUserInputLineIdx+1:], "\n")
@@ -234,6 +241,7 @@ const (
 	AgentTypeCursorAgent AgentType = "cursor-agent"
 	AgentTypeCursor      AgentType = "cursor"
 	AgentTypeAuggie      AgentType = "auggie"
+	AgentTypeOpencode    AgentType = "opencode"
 	AgentTypeCustom      AgentType = "custom"
 )
 
@@ -251,6 +259,13 @@ func formatCodexMessage(message string, userInput string) string {
 	return message
 }
 
+func formatOpencodeMessage(message string, userInput string) string {
+	message = RemoveUserInput(message, userInput, AgentTypeOpencode)
+	message = removeOpencodeMessageBox(message)
+	message = trimEmptyLines(message)
+	return message
+}
+
 func FormatAgentMessage(agentType AgentType, message string, userInput string) string {
 	switch agentType {
 	case AgentTypeClaude:
@@ -271,6 +286,8 @@ func FormatAgentMessage(agentType AgentType, message string, userInput string) s
 		return formatGenericMessage(message, userInput, agentType)
 	case AgentTypeAuggie:
 		return formatGenericMessage(message, userInput, agentType)
+	case AgentTypeOpencode:
+		return formatOpencodeMessage(message, userInput)
 	case AgentTypeCustom:
 		return formatGenericMessage(message, userInput, agentType)
 	default:

lib/msgfmt/msgfmt_test.go

@@ -218,7 +218,7 @@ func TestTrimEmptyLines(t *testing.T) {
 
 func TestFormatAgentMessage(t *testing.T) {
 	dir := "testdata/format"
-	agentTypes := []AgentType{AgentTypeClaude, AgentTypeGoose, AgentTypeAider, AgentTypeGemini, AgentTypeAmp, AgentTypeCodex, AgentTypeCursorAgent, AgentTypeCursor, AgentTypeAuggie, AgentTypeCustom}
+	agentTypes := []AgentType{AgentTypeClaude, AgentTypeGoose, AgentTypeAider, AgentTypeGemini, AgentTypeAmp, AgentTypeCodex, AgentTypeCursorAgent, AgentTypeCursor, AgentTypeAuggie, AgentTypeOpencode, AgentTypeCustom}
 	for _, agentType := range agentTypes {
 		t.Run(string(agentType), func(t *testing.T) {
 			cases, err := testdataDir.ReadDir(path.Join(dir, string(agentType)))

lib/screentracker/conversation.go

@@ -24,7 +24,8 @@ type AgentIO interface {
 }
 
 type ConversationConfig struct {
-	AgentIO AgentIO
+	AgentType msgfmt.AgentType
+	AgentIO   AgentIO
 	// GetTime returns the current time
 	GetTime func() time.Time
 	// How often to take a snapshot for the stability check
@@ -133,15 +134,29 @@ func (c *Conversation) StartSnapshotLoop(ctx context.Context) {
 	}()
 }
 
-func FindNewMessage(oldScreen, newScreen string) string {
+func FindNewMessage(oldScreen, newScreen string, agentType msgfmt.AgentType) string {
 	oldLines := strings.Split(oldScreen, "\n")
 	newLines := strings.Split(newScreen, "\n")
 	oldLinesMap := make(map[string]bool)
+
+	// -1 indicates no header
+	dynamicHeaderEnd := -1
+
+	// Skip header lines for Opencode agent type to avoid false positives
+	// The header contains dynamic content (token count, context percentage, cost)
+	// that changes between screens, causing line comparison mismatches:
+	//
+	// ┃  # Getting Started with Claude CLI                                   ┃
+	// ┃  /share to create a shareable link                 12.6K/6% ($0.05)  ┃
+	if len(newLines) >= 2 && agentType == msgfmt.AgentTypeOpencode {
+		dynamicHeaderEnd = 2
+	}
+
 	for _, line := range oldLines {
 		oldLinesMap[line] = true
 	}
 	firstNonMatchingLine := len(newLines)
-	for i, line := range newLines {
+	for i, line := range newLines[dynamicHeaderEnd+1:] {
 		if !oldLinesMap[line] {
 			firstNonMatchingLine = i
 			break
@@ -178,7 +193,7 @@ func (c *Conversation) lastMessage(role ConversationRole) ConversationMessage {
 
 // This function assumes that the caller holds the lock
 func (c *Conversation) updateLastAgentMessage(screen string, timestamp time.Time) {
-	agentMessage := FindNewMessage(c.screenBeforeLastUserMessage, screen)
+	agentMessage := FindNewMessage(c.screenBeforeLastUserMessage, screen, c.cfg.AgentType)
 	lastUserMessage := c.lastMessage(ConversationRoleUser)
 	if c.cfg.FormatMessage != nil {
 		agentMessage = c.cfg.FormatMessage(agentMessage, lastUserMessage.Message)