Fix opencode PRD conversion by extracting JSON from NDJSON output

Author: tpaulshippy

internal/agent/claude.go

@@ -68,3 +68,6 @@ func (p *ClaudeProvider) ParseLine(line string) *loop.Event {
 
 // LogFileName implements loop.Provider.
 func (p *ClaudeProvider) LogFileName() string { return "claude.log" }
+
+// CleanOutput implements loop.Provider - Claude doesn't use a special format.
+func (p *ClaudeProvider) CleanOutput(output string) string { return output }

internal/agent/codex.go

@@ -79,3 +79,6 @@ func (p *CodexProvider) ParseLine(line string) *loop.Event {
 
 // LogFileName implements loop.Provider.
 func (p *CodexProvider) LogFileName() string { return "codex.log" }
+
+// CleanOutput implements loop.Provider - Codex doesn't use a special format.
+func (p *CodexProvider) CleanOutput(output string) string { return output }

internal/agent/opencode.go

@@ -2,6 +2,7 @@ package agent
 
 import (
 	"context"
+	"encoding/json"
 	"os/exec"
 	"strings"
 
@@ -53,3 +54,32 @@ func (p *OpenCodeProvider) ParseLine(line string) *loop.Event {
 }
 
 func (p *OpenCodeProvider) LogFileName() string { return "opencode.log" }
+
+// CleanOutput extracts JSON from opencode's NDJSON output format.
+func (p *OpenCodeProvider) CleanOutput(output string) string {
+	output = strings.TrimSpace(output)
+
+	if !strings.Contains(output, "\n") || !strings.Contains(output, `"type":"step_start"`) || !strings.Contains(output, `"type":"text"`) {
+		return output
+	}
+
+	lines := strings.Split(output, "\n")
+	for _, line := range lines {
+		line = strings.TrimSpace(line)
+		if line == "" {
+			continue
+		}
+		if strings.Contains(line, `"type":"text"`) {
+			var ev struct {
+				Type string `json:"type"`
+				Part struct {
+					Text string `json:"text"`
+				} `json:"part"`
+			}
+			if json.Unmarshal([]byte(line), &ev) == nil && ev.Part.Text != "" {
+				return ev.Part.Text
+			}
+		}
+	}
+	return output
+}

internal/cmd/new.go

@@ -120,10 +120,18 @@ func RunConvertWithOptions(opts ConvertOptions) error {
 		Merge:  opts.Merge,
 		Force:  opts.Force,
 		RunConversion: func(absPRDDir string) (string, error) {
-			return runConversionWithProvider(provider, absPRDDir)
+			raw, err := runConversionWithProvider(provider, absPRDDir)
+			if err != nil {
+				return "", err
+			}
+			return provider.CleanOutput(raw), nil
 		},
 		RunFixJSON: func(prompt string) (string, error) {
-			return runFixJSONWithProvider(provider, prompt)
+			raw, err := runFixJSONWithProvider(provider, prompt)
+			if err != nil {
+				return "", err
+			}
+			return provider.CleanOutput(raw), nil
 		},
 	})
 }

internal/loop/provider.go

@@ -24,6 +24,9 @@ type Provider interface {
 	InteractiveCommand(workDir, prompt string) *exec.Cmd
 	ConvertCommand(workDir, prompt string) (cmd *exec.Cmd, mode OutputMode, outPath string, err error)
 	FixJSONCommand(prompt string) (cmd *exec.Cmd, mode OutputMode, outPath string, err error)
+	// CleanOutput extracts JSON from the provider's output format (e.g., NDJSON).
+	// Returns the original output if no cleaning needed.
+	CleanOutput(output string) string
 	ParseLine(line string) *Event
 	LogFileName() string
 }

internal/prd/generator.go

@@ -54,9 +54,9 @@ var waitingJokes = []string{
 
 // ConvertOptions contains configuration for PRD conversion.
 type ConvertOptions struct {
-	PRDDir   string // Directory containing prd.md
-	Merge    bool   // Auto-merge progress on conversion conflicts
-	Force    bool   // Auto-overwrite on conversion conflicts
+	PRDDir string // Directory containing prd.md
+	Merge  bool   // Auto-merge progress on conversion conflicts
+	Force  bool   // Auto-overwrite on conversion conflicts
 	// RunConversion runs the agent to convert prd.md to JSON. Required.
 	RunConversion func(absPRDDir string) (string, error)
 	// RunFixJSON runs the agent to fix invalid JSON. Required.
@@ -117,7 +117,7 @@ func Convert(opts ConvertOptions) error {
 	}
 
 	// Clean up output (strip markdown fences if any)
-	cleanedJSON := cleanJSONOutput(rawJSON)
+	cleanedJSON := stripMarkdownFences(rawJSON)
 
 	// Parse and validate
 	newPRD, err := parseAndValidatePRD(cleanedJSON)
@@ -130,7 +130,7 @@ func Convert(opts ConvertOptions) error {
 			return fmt.Errorf("conversion retry failed: %w", retryErr)
 		}
 
-		cleanedJSON = cleanJSONOutput(fixedJSON)
+		cleanedJSON = stripMarkdownFences(fixedJSON)
 		newPRD, err = parseAndValidatePRD(cleanedJSON)
 		if err != nil {
 			return fmt.Errorf("conversion produced invalid JSON after retry:\n---\n%s\n---\n%w", cleanedJSON, err)
@@ -555,9 +555,9 @@ func NeedsConversion(prdDir string) (bool, error) {
 	return mdInfo.ModTime().After(jsonInfo.ModTime()), nil
 }
 
-// cleanJSONOutput removes markdown code blocks, conversational preamble, and trims
-// whitespace from Claude's output to extract the JSON object.
-func cleanJSONOutput(output string) string {
+// stripMarkdownFences removes markdown code blocks and extracts the JSON object.
+// This handles output from providers like Claude that may wrap JSON in markdown fences.
+func stripMarkdownFences(output string) string {
 	output = strings.TrimSpace(output)
 
 	// Remove markdown code blocks if present
@@ -573,7 +573,7 @@ func cleanJSONOutput(output string) string {
 
 	output = strings.TrimSpace(output)
 
-	// If output doesn't start with '{', Claude may have added preamble text.
+	// If output doesn't start with '{', the provider may have added preamble text.
 	// Extract the JSON object by finding the first '{' and matching closing '}'.
 	if len(output) > 0 && output[0] != '{' {
 		start := strings.Index(output, "{")

internal/prd/generator_test.go

@@ -8,7 +8,7 @@ import (
 	"time"
 )
 
-func TestCleanJSONOutput(t *testing.T) {
+func TestStripMarkdownFences(t *testing.T) {
 	tests := []struct {
 		name     string
 		input    string
@@ -63,9 +63,9 @@ func TestCleanJSONOutput(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			result := cleanJSONOutput(tt.input)
+			result := stripMarkdownFences(tt.input)
 			if result != tt.expected {
-				t.Errorf("cleanJSONOutput() = %q, want %q", result, tt.expected)
+				t.Errorf("stripMarkdownFences() = %q, want %q", result, tt.expected)
 			}
 		})
 	}