diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index d036c6542d..41aa66dcad 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -1558,6 +1558,18 @@ export const layer = Layer.effect(
       }
 
       const templateParts = yield* resolvePromptParts(template)
+      const stripParams = (url: string) => {
+        const u = new URL(url)
+        u.search = ""
+        u.hash = ""
+        return u.href
+      }
+      const inputFileUrls = new Set(
+        (input.parts ?? []).flatMap((p) => (p.type === "file" ? [stripParams(p.url)] : [])),
+      )
+      const dedupedTemplateParts = templateParts.filter(
+        (p) => !(p.type === "file" && inputFileUrls.has(stripParams(p.url))),
+      )
       const isSubtask = (agent.mode === "subagent" && cmd.subtask !== false) || cmd.subtask === true
       const parts = isSubtask
         ? [
@@ -1570,7 +1582,7 @@ export const layer = Layer.effect(
               prompt: templateParts.find((y) => y.type === "text")?.text ?? "",
             },
           ]
-        : [...templateParts, ...(input.parts ?? [])]
+        : [...dedupedTemplateParts, ...(input.parts ?? [])]
 
       const userAgent = isSubtask ? (input.agent ?? (yield* agents.defaultInfo()).name) : agent.name
       const userModel = isSubtask