Remove legacy claude field and working_dir backward compat

- Remove Claude field alias from Task struct (already removed in sandbox)
- Remove UnmarshalJSON from AgentConfig that silently accepted working_dir
- Remove legacy claude fallback in scanTask (db.go)
- Remove TestGetTask_BackwardCompatibility test that validated removed behavior

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

3 files changed, 0 insertions, 60 deletions

diff --git a/internal/storage/db.go b/internal/storage/db.go
index 835ac29..31d38ed 100644
--- a/internal/storage/db.go
+++ b/internal/storage/db.go
@@ -519,15 +519,6 @@ func scanTask(row scanner) (*task.Task, error) {
 	if err := json.Unmarshal([]byte(configJSON), &t.Agent); err != nil {
 		return nil, fmt.Errorf("unmarshaling agent config: %w", err)
 	}
-	// Fallback for legacy 'claude' field
-	if t.Agent.Instructions == "" {
-		var legacy struct {
-			Claude task.AgentConfig `json:"claude"`
-		}
-		if err := json.Unmarshal([]byte(configJSON), &legacy); err == nil && legacy.Claude.Instructions != "" {
-			t.Agent = legacy.Claude
-		}
-	}
 	if err := json.Unmarshal([]byte(retryJSON), &t.Retry); err != nil {
 		return nil, fmt.Errorf("unmarshaling retry: %w", err)
 	}
diff --git a/internal/storage/db_test.go b/internal/storage/db_test.go
index 5f786ac..d28a4a8 100644
--- a/internal/storage/db_test.go
+++ b/internal/storage/db_test.go
@@ -733,35 +733,3 @@ func TestListRecentExecutions_LargeDataset(t *testing.T) {
 	})
 }
 
-func TestGetTask_BackwardCompatibility(t *testing.T) {
-	db := testDB(t)
-	now := time.Now().UTC().Truncate(time.Second)
-
-	// Legacy config JSON using "claude" field instead of "agent"
-	legacyConfig := `{"claude":{"model":"haiku","instructions":"legacy instructions","max_budget_usd":0.5}}`
-
-	_, err := db.db.Exec(`
-		INSERT INTO tasks (id, name, description, config_json, priority, timeout_ns, retry_json, tags_json, depends_on_json, state, created_at, updated_at)
-		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
-		"legacy-id", "Legacy Task", "A legacy test", legacyConfig, "normal",
-		0, "{}", "[]", "[]", "PENDING", now, now,
-	)
-	if err != nil {
-		t.Fatalf("inserting legacy task: %v", err)
-	}
-
-	got, err := db.GetTask("legacy-id")
-	if err != nil {
-		t.Fatalf("getting legacy task: %v", err)
-	}
-
-	if got.Agent.Instructions != "legacy instructions" {
-		t.Errorf("instructions: want 'legacy instructions', got %q", got.Agent.Instructions)
-	}
-	if got.Agent.Model != "haiku" {
-		t.Errorf("model: want 'haiku', got %q", got.Agent.Model)
-	}
-	if got.Agent.MaxBudgetUSD != 0.5 {
-		t.Errorf("budget: want 0.5, got %f", got.Agent.MaxBudgetUSD)
-	}
-}
diff --git a/internal/task/task.go b/internal/task/task.go
index 4977f40..c0aa036 100644
--- a/internal/task/task.go
+++ b/internal/task/task.go
@@ -1,7 +1,6 @@
 package task
 
 import (
-	"encoding/json"
 	"time"
 )
 
@@ -43,24 +42,6 @@ type AgentConfig struct {
 	SkipPlanning       bool     `yaml:"skip_planning"       json:"skip_planning"`
 }
 
-// UnmarshalJSON reads project_dir with fallback to legacy working_dir.
-func (c *AgentConfig) UnmarshalJSON(data []byte) error {
-	type Alias AgentConfig
-	aux := &struct {
-		ProjectDir string `json:"project_dir"`
-		WorkingDir string `json:"working_dir"` // legacy
-		*Alias
-	}{Alias: (*Alias)(c)}
-	if err := json.Unmarshal(data, aux); err != nil {
-		return err
-	}
-	if aux.ProjectDir != "" {
-		c.ProjectDir = aux.ProjectDir
-	} else {
-		c.ProjectDir = aux.WorkingDir
-	}
-	return nil
-}
 
 type RetryConfig struct {
 	MaxAttempts int    `yaml:"max_attempts" json:"max_attempts"`