tweak(edit): separate edit tool error message with clearer guidance to avoid llm doom editing loop (anomalyco#2051)

spoons-and-mirrors · web-flow · commit 900fe5ca041c · 2025-09-05T12:36:13.000-04:00
diff --git a/packages/opencode/src/tool/edit.ts b/packages/opencode/src/tool/edit.ts
@@ -594,6 +594,8 @@ export function replace(content: string, oldString: string, newString: string, r
     throw new Error("oldString and newString must be different")
   }
 
+  let notFound = true
+
   for (const replacer of [
     SimpleReplacer,
     LineTrimmedReplacer,
@@ -608,6 +610,7 @@ export function replace(content: string, oldString: string, newString: string, r
     for (const search of replacer(content, oldString)) {
       const index = content.indexOf(search)
       if (index === -1) continue
+      notFound = false
       if (replaceAll) {
         return content.replaceAll(search, newString)
       }
@@ -616,5 +619,9 @@ export function replace(content: string, oldString: string, newString: string, r
       return content.substring(0, index) + newString + content.substring(index + search.length)
     }
   }
-  throw new Error("oldString not found in content or was found multiple times")
+
+  if (notFound) {
+    throw new Error("oldString not found in content")
+  }
+  throw new Error("oldString found multiple times and requires more code context to uniquely identify the intended match")
 }
diff --git a/packages/opencode/src/tool/edit.txt b/packages/opencode/src/tool/edit.txt
@@ -5,5 +5,6 @@ Usage:
 - When editing text from Read tool output, ensure you preserve the exact indentation (tabs/spaces) as it appears AFTER the line number prefix. The line number prefix format is: spaces + line number + tab. Everything after that tab is the actual file content to match. Never include any part of the line number prefix in the oldString or newString.
 - ALWAYS prefer editing existing files in the codebase. NEVER write new files unless explicitly required.
 - Only use emojis if the user explicitly requests it. Avoid adding emojis to files unless asked.
-- The edit will FAIL if `oldString` is not unique in the file. Either provide a larger string with more surrounding context to make it unique or use `replaceAll` to change every instance of `oldString`. 
+- The edit will FAIL if `oldString` is not found in the file with an error "oldString not found in content".
+- The edit will FAIL if `oldString` is found multiple times in the file with an error "oldString found multiple times and requires more code context to uniquely identify the intended match". Either provide a larger string with more surrounding context to make it unique or use `replaceAll` to change every instance of `oldString`. 
 - Use `replaceAll` for replacing and renaming strings across the file. This parameter is useful if you want to rename a variable for instance.

Original file line number	Diff line number	Diff line change
`@@ -594,6 +594,8 @@ export function replace(content: string, oldString: string, newString: string, r`
`594`	`594`	`throw new Error("oldString and newString must be different")`
`595`	`595`	`}`
`596`	`596`
	`597`	`+ let notFound = true`
	`598`	`+`
`597`	`599`	`for (const replacer of [`
`598`	`600`	`SimpleReplacer,`
`599`	`601`	`LineTrimmedReplacer,`
`@@ -608,6 +610,7 @@ export function replace(content: string, oldString: string, newString: string, r`
`608`	`610`	`for (const search of replacer(content, oldString)) {`
`609`	`611`	`const index = content.indexOf(search)`
`610`	`612`	`if (index === -1) continue`
	`613`	`+ notFound = false`
`611`	`614`	`if (replaceAll) {`
`612`	`615`	`return content.replaceAll(search, newString)`
`613`	`616`	`}`
`@@ -616,5 +619,9 @@ export function replace(content: string, oldString: string, newString: string, r`
`616`	`619`	`return content.substring(0, index) + newString + content.substring(index + search.length)`
`617`	`620`	`}`
`618`	`621`	`}`
`619`		`- throw new Error("oldString not found in content or was found multiple times")`
	`622`	`+`
	`623`	`+ if (notFound) {`
	`624`	`+ throw new Error("oldString not found in content")`
	`625`	`+ }`
	`626`	`+ throw new Error("oldString found multiple times and requires more code context to uniquely identify the intended match")`
`620`	`627`	`}`