feat(agent): gpt-5.4-mini/mature pass 1

Commit:

Co-Authored-By: Virgil <virgil@lethean.io>

.core/TODO.md

@@ -0,0 +1,2 @@
+- @bug pkg/agentic/deps.go:59 — `go.work` is written without checking the result, so dependency cloning can fail silently.
+- @bug pkg/agentic/prep.go:835 — the PHP-specific `CODEX.md` overwrite ignores write failures, leaving prep to continue with a partial workspace.

pkg/agentic/prep.go

@@ -796,6 +796,9 @@ func (s *PrepSubsystem) prepWorkspace(ctx context.Context, _ *mcp.CallToolReques
 		}
 		return nil, PrepOutput{}, core.E("prepWorkspace", "extract default workspace template", nil)
 	}
+	if err := ensureWorkspaceTaskFile(workspaceDir); err != nil {
+		return nil, PrepOutput{}, err
+	}
 
 	if !resumed {
 		if r := process.RunIn(ctx, ".", "git", "clone", repoPath, repoDir); !r.OK {
@@ -1021,6 +1024,32 @@ func (s *PrepSubsystem) buildPrompt(ctx context.Context, input PrepInput, branch
 	return promptBuilder.String(), memoryCount, consumerCount
 }
 
+// ensureWorkspaceTaskFile("/srv/.core/workspace/core/go-io/task-42")
+// keeps TODO.md present for the prompt and the local agent shell wrapper.
+func ensureWorkspaceTaskFile(workspaceDir string) error {
+	todoPath := core.JoinPath(workspaceDir, "TODO.md")
+	if readResult := fs.Read(todoPath); readResult.OK && core.Trim(readResult.Value.(string)) != "" {
+		return nil
+	}
+
+	templateResult := lib.WorkspaceFile("default", "TODO.md.tmpl")
+	if !templateResult.OK {
+		if err, ok := templateResult.Value.(error); ok {
+			return core.E("prepWorkspace", "load TODO.md template", err)
+		}
+		return core.E("prepWorkspace", "load TODO.md template", nil)
+	}
+
+	if writeResult := fs.Write(todoPath, templateResult.Value.(string)); !writeResult.OK {
+		if err, ok := writeResult.Value.(error); ok {
+			return core.E("prepWorkspace", "write TODO.md", err)
+		}
+		return core.E("prepWorkspace", "write TODO.md", nil)
+	}
+
+	return nil
+}
+
 // writePromptSnapshot stores an immutable prompt snapshot for a workspace.
 //
 //	snapshot := writePromptSnapshot("/srv/.core/workspace/core/go-io/task-42", "TASK: Fix tests")

pkg/agentic/prep_test.go

@@ -1228,6 +1228,12 @@ func TestPrep_PrepWorkspace_Good(t *testing.T) {
 
 	promptSnapshotPath := core.JoinPath(WorkspaceMetaDir(out.WorkspaceDir), "prompt-versions", core.Concat(out.PromptVersion, ".json"))
 	require.True(t, fs.Exists(promptSnapshotPath))
+
+	todoPath := core.JoinPath(out.WorkspaceDir, "TODO.md")
+	require.True(t, fs.Exists(todoPath))
+	todoResult := fs.Read(todoPath)
+	require.True(t, todoResult.OK)
+	assert.NotEmpty(t, core.Trim(todoResult.Value.(string)))
 }
 
 func TestPrep_TestPrepWorkspace_Good(t *testing.T) {
@@ -1274,6 +1280,12 @@ func TestPrep_TestPrepWorkspace_Good(t *testing.T) {
 	require.NoError(t, err)
 	assert.True(t, out.Success)
 	assert.NotEmpty(t, out.WorkspaceDir)
+
+	todoPath := core.JoinPath(out.WorkspaceDir, "TODO.md")
+	require.True(t, fs.Exists(todoPath))
+	todoResult := fs.Read(todoPath)
+	require.True(t, todoResult.OK)
+	assert.NotEmpty(t, core.Trim(todoResult.Value.(string)))
 }
 
 func TestPrep_TestPrepWorkspace_Bad(t *testing.T) {