diff --git a/packages/opencode/src/acp/content.ts b/packages/opencode/src/acp/content.ts
index 5f149d85f0f2..45c61aa03ca9 100644
--- a/packages/opencode/src/acp/content.ts
+++ b/packages/opencode/src/acp/content.ts
@@ -1,6 +1,6 @@
 import type { ContentBlock, ContentChunk, ResourceLink, Role } from "@agentclientprotocol/sdk"
 import path from "node:path"
-import { pathToFileURL } from "node:url"
+import { fileURLToPath, pathToFileURL } from "node:url"
 import { SessionV1 } from "@opencode-ai/core/v1/session"
 
 export type PromptPart = SessionV1.TextPartInput | SessionV1.FilePartInput
@@ -76,7 +76,11 @@ export function contentBlockToParts(block: ContentBlock): PromptPart[] {
 
     case "resource":
       if ("text" in block.resource) {
-        return [{ type: "text", text: block.resource.text }]
+        // Prefix the selected text with its source location when the editor
+        // (e.g. Zed) supplies a `file://` uri, so the LLM and session replays
+        // can trace the snippet back to its file (and line range). See #32558.
+        const source = fileSourcePrefix(block.resource.uri)
+        return [{ type: "text", text: source ? `${source}\n${block.resource.text}` : block.resource.text }]
       }
       if (block.resource.mimeType) {
         return [
@@ -237,6 +241,21 @@ function partAudience(part: Extract<ReplayPart, { type: "text" }>) {
   return { annotations: { audience } }
 }
 
+function fileSourcePrefix(uri: string | undefined) {
+  if (!uri || !uri.startsWith("file://")) return undefined
+  try {
+    const hashIndex = uri.indexOf("#")
+    const base = hashIndex === -1 ? uri : uri.slice(0, hashIndex)
+    const fragment = hashIndex === -1 ? "" : uri.slice(hashIndex + 1)
+    const filePath = fileURLToPath(base)
+    // ACP encodes line ranges as a `#L12` or `#L12-15` fragment.
+    const lines = /^L?(\d+(?:-\d+)?)/.exec(fragment)
+    return `[${filePath}${lines ? `:${lines[1]}` : ""}]`
+  } catch {
+    return undefined
+  }
+}
+
 function filenameFromUri(uri: string | undefined) {
   if (!uri) return
   if (uri.startsWith("data:")) return
diff --git a/packages/opencode/test/acp/content.test.ts b/packages/opencode/test/acp/content.test.ts
index 90f62f9d1892..22f5ad2269ad 100644
--- a/packages/opencode/test/acp/content.test.ts
+++ b/packages/opencode/test/acp/content.test.ts
@@ -1,5 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import type { ContentBlock } from "@agentclientprotocol/sdk"
+import path from "node:path"
 import { pathToFileURL } from "node:url"
 import { contentBlockToParts, partsToContentChunks, promptContentToParts } from "../../src/acp/content"
 
@@ -99,12 +100,40 @@ describe("acp content conversion", () => {
     ])
   })
 
-  test("resource with text becomes a text part", () => {
+  test("resource with text prefixes the file source location", () => {
+    const filePath = path.resolve("tmp", "context.txt")
     expect(
       contentBlockToParts({
         type: "resource",
         resource: {
-          uri: "file:///tmp/context.txt",
+          uri: pathToFileURL(filePath).href,
+          mimeType: "text/plain",
+          text: "context",
+        },
+      }),
+    ).toEqual([{ type: "text", text: `[${filePath}]\ncontext` }])
+  })
+
+  test("resource with text includes the line range from the uri fragment", () => {
+    const filePath = path.resolve("tmp", "app.ts")
+    expect(
+      contentBlockToParts({
+        type: "resource",
+        resource: {
+          uri: `${pathToFileURL(filePath).href}#L12-15`,
+          mimeType: "text/typescript",
+          text: "const x = 1",
+        },
+      }),
+    ).toEqual([{ type: "text", text: `[${filePath}:12-15]\nconst x = 1` }])
+  })
+
+  test("resource with text and a non-file uri is left untouched", () => {
+    expect(
+      contentBlockToParts({
+        type: "resource",
+        resource: {
+          uri: "https://example.com/notes",
           mimeType: "text/plain",
           text: "context",
         },