feat: support opencode (#79)

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

@@ -23,16 +23,17 @@ import (
 type AgentType = msgfmt.AgentType
 
 const (
-	AgentTypeClaude  AgentType = msgfmt.AgentTypeClaude
-	AgentTypeGoose   AgentType = msgfmt.AgentTypeGoose
-	AgentTypeAider   AgentType = msgfmt.AgentTypeAider
-	AgentTypeCodex   AgentType = msgfmt.AgentTypeCodex
-	AgentTypeGemini  AgentType = msgfmt.AgentTypeGemini
-	AgentTypeAmp     AgentType = msgfmt.AgentTypeAmp
-	AgentTypeCursor  AgentType = msgfmt.AgentTypeCursor
-	AgentTypeAuggie  AgentType = msgfmt.AgentTypeAuggie
-	AgentTypeAmazonQ AgentType = msgfmt.AgentTypeAmazonQ
-	AgentTypeCustom  AgentType = msgfmt.AgentTypeCustom
+	AgentTypeClaude   AgentType = msgfmt.AgentTypeClaude
+	AgentTypeGoose    AgentType = msgfmt.AgentTypeGoose
+	AgentTypeAider    AgentType = msgfmt.AgentTypeAider
+	AgentTypeCodex    AgentType = msgfmt.AgentTypeCodex
+	AgentTypeGemini   AgentType = msgfmt.AgentTypeGemini
+	AgentTypeAmp      AgentType = msgfmt.AgentTypeAmp
+	AgentTypeCursor   AgentType = msgfmt.AgentTypeCursor
+	AgentTypeAuggie   AgentType = msgfmt.AgentTypeAuggie
+	AgentTypeAmazonQ  AgentType = msgfmt.AgentTypeAmazonQ
+	AgentTypeOpencode AgentType = msgfmt.AgentTypeOpencode
+	AgentTypeCustom   AgentType = msgfmt.AgentTypeCustom
 )
 
 // agentTypeAliases contains the mapping of possible input agent type strings to their canonical AgentType values
@@ -48,6 +49,7 @@ var agentTypeAliases = map[string]AgentType{
 	"cursor-agent": AgentTypeCursor,
 	"q":            AgentTypeAmazonQ,
 	"amazonq":      AgentTypeAmazonQ,
+	"opencode":     AgentTypeOpencode,
 	"custom":       AgentTypeCustom,
 }
 

cmd/server/server_test.go

@@ -67,6 +67,11 @@ func TestParseAgentType(t *testing.T) {
 			agentTypeVar: "",
 			want:         AgentTypeAmazonQ,
 		},
+		{
+			firstArg:     "opencode",
+			agentTypeVar: "",
+			want:         AgentTypeOpencode,
+		},
 		{
 			firstArg:     "auggie",
 			agentTypeVar: "",
@@ -117,6 +122,11 @@ func TestParseAgentType(t *testing.T) {
 			agentTypeVar: "q",
 			want:         AgentTypeAmazonQ,
 		},
+		{
+			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 +60,22 @@ 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 input block does not load within a snapshot,
+	// this leads to displaying a bunch of newlines.
+	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 (
 	AgentTypeCursor  AgentType = "cursor"
 	AgentTypeAuggie  AgentType = "auggie"
 	AgentTypeAmazonQ AgentType = "amazonq"
+	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 AgentTypeAmazonQ:
 		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, AgentTypeCursor, AgentTypeAuggie, AgentTypeAmazonQ, AgentTypeCustom}
+	agentTypes := []AgentType{AgentTypeClaude, AgentTypeGoose, AgentTypeAider, AgentTypeGemini, AgentTypeAmp, AgentTypeCodex, AgentTypeCursor, AgentTypeAuggie, AgentTypeAmazonQ, AgentTypeOpencode, AgentTypeCustom}
 	for _, agentType := range agentTypes {
 		t.Run(string(agentType), func(t *testing.T) {
 			cases, err := testdataDir.ReadDir(path.Join(dir, string(agentType)))

lib/msgfmt/testdata/format/opencode/first_message/expected.txt

@@ -0,0 +1,12 @@
+                    █▀▀█ █▀▀█ █▀▀ █▀▀▄ █▀▀ █▀▀█ █▀▀▄ █▀▀
+                    █░░█ █░░█ █▀▀ █░░█ █░░ █░░█ █░░█ █▀▀
+                    ▀▀▀▀ █▀▀▀ ▀▀▀ ▀  ▀ ▀▀▀ ▀▀▀▀ ▀▀▀  ▀▀▀
+                                                  v0.6.8
+
+                     /new      new session     ctrl+x n
+                     /help     show help       ctrl+x h
+                     /share    share session   ctrl+x s
+                     /models   list models     ctrl+x m
+
+
+                    Grok Code is free for a limited time