diff --git a/TODO.md b/TODO.md
index 9791b16..09387b8 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,7 +1,5 @@
-[lang1] `load` -- use `Report` instead of `LangError`
-[lang0] `load` -- use `Report` instead of `LangError`
-[lang1] `Lang1Command` -- catch `Report`
-[lang0] `Lang0Command` -- catch `Report`
+[lang0] remove `ErrorReport`
+
 [lang0] add snapshot test for error report
 
 # lang1
@@ -12,6 +10,7 @@
 
 # docs
 
+[docs/lang0] simple readme like inet
 [docs/lang0] 用中文重新整理 lambda encoding 相关的知识。
 [docs/lang0] 用中文重新整理 lambda encoding 和 self type 相关的知识。
 
diff --git a/src/command-line/commands/Lang1Command.ts b/src/command-line/commands/Lang1Command.ts
index 2599cda..24a2a44 100644
--- a/src/command-line/commands/Lang1Command.ts
+++ b/src/command-line/commands/Lang1Command.ts
@@ -33,8 +33,12 @@ export class Lang1Command extends Command<Args, Opts> {
     try {
       await run(url)
     } catch (error) {
-      console.error(error)
-      process.exit(1)
+      if (error instanceof Error) {
+        console.error(error.message)
+        process.exit(1)
+      }
+
+      throw error
     }
   }
 }
diff --git a/src/lang1/errors/ErrorReport.ts b/src/lang1/errors/ErrorReport.ts
deleted file mode 100644
index c1e06e0..0000000
--- a/src/lang1/errors/ErrorReport.ts
+++ /dev/null
@@ -1,7 +0,0 @@
-import { LangError } from "./LangError.js"
-
-export class ErrorReport extends LangError {
-  constructor(public message: string) {
-    super(message)
-  }
-}
diff --git a/src/lang1/errors/index.ts b/src/lang1/errors/index.ts
index 0c64caa..7a58de4 100644
--- a/src/lang1/errors/index.ts
+++ b/src/lang1/errors/index.ts
@@ -1,2 +1 @@
-export * from "./ErrorReport.js"
 export * from "./LangError.js"
diff --git a/src/lang1/run/load.ts b/src/lang1/run/load.ts
index 87108b6..b17b699 100644
--- a/src/lang1/run/load.ts
+++ b/src/lang1/run/load.ts
@@ -1,7 +1,6 @@
 import { Fetcher } from "@cicada-lang/framework/lib/fetcher/index.js"
 import { ParsingError } from "@cicada-lang/sexp"
 import fs from "node:fs"
-import * as Errors from "../errors/index.js"
 import { createMod, type Mod } from "../mod/index.js"
 import { type Stmt } from "../stmt/index.js"
 import { Parser } from "../syntax/index.js"
@@ -36,7 +35,7 @@ export async function load(
     return mod
   } catch (error) {
     if (error instanceof ParsingError) {
-      throw new Errors.ErrorReport(error.report(text))
+      throw new Error(error.report(text))
     }
 
     throw error