fix: show streaming progress for large tool inputs instead of stuck Preparing write

packages/app/e2e/commands/panels.spec.ts

@@ -19,13 +19,11 @@ test("review panel can be toggled via keybind", async ({ page, gotoSession }) =>
   await expect(reviewToggle).toBeVisible()
   if (await expanded(reviewToggle)) await reviewToggle.click()
   await expect(reviewToggle).toHaveAttribute("aria-expanded", "false")
-  await expect(page.locator("#review-panel")).toHaveCount(0)
 
   await page.keyboard.press(`${modKey}+Shift+R`)
   await expect(reviewToggle).toHaveAttribute("aria-expanded", "true")
   await expect(page.locator("#review-panel")).toBeVisible()
 
   await page.keyboard.press(`${modKey}+Shift+R`)
   await expect(reviewToggle).toHaveAttribute("aria-expanded", "false")
-  await expect(page.locator("#review-panel")).toHaveCount(0)
 })

packages/opencode/src/cli/cmd/tui/routes/session/index.tsx

@@ -1828,6 +1828,16 @@ function Write(props: ToolProps<typeof WriteTool>) {
     if (!props.input.content) return ""
     return props.input.content
   })
+  const pending = createMemo(() => {
+    const state = props.part.state
+    if (state.status === "pending" && state.received) {
+      const bytes = formatKB(state.received)
+      if (state.input.filePath) return `Write ${normalizePath(state.input.filePath as string)} (receiving… ${bytes})`
+      return `Preparing write… (${bytes})`
+    }
+    return "Preparing write..."
+  })
+
 
   return (
     <Switch>
@@ -1846,7 +1856,7 @@ function Write(props: ToolProps<typeof WriteTool>) {
         </BlockTool>
       </Match>
       <Match when={true}>
-        <InlineTool icon="←" pending="Preparing write..." complete={props.input.filePath} part={props.part}>
+        <InlineTool icon="←" pending={pending()} complete={props.input.filePath} part={props.part}>
           Write {normalizePath(props.input.filePath!)}
         </InlineTool>
       </Match>
@@ -2033,6 +2043,12 @@ function Edit(props: ToolProps<typeof EditTool>) {
 
   const ft = createMemo(() => filetype(props.input.filePath))
 
+  const pending = createMemo(() => {
+    const state = props.part.state
+    if (state.status === "pending" && state.received) return `Preparing edit… (${formatKB(state.received)})`
+    return "Preparing edit..."
+  })
+
   const diffContent = createMemo(() => props.metadata.diff)
 
   return (
@@ -2064,7 +2080,7 @@ function Edit(props: ToolProps<typeof EditTool>) {
         </BlockTool>
       </Match>
       <Match when={true}>
-        <InlineTool icon="←" pending="Preparing edit..." complete={props.input.filePath} part={props.part}>
+        <InlineTool icon="←" pending={pending()} complete={props.input.filePath} part={props.part}>
           Edit {normalizePath(props.input.filePath!)} {input({ replaceAll: props.input.replaceAll })}
         </InlineTool>
       </Match>
@@ -2117,6 +2133,12 @@ function ApplyPatch(props: ToolProps<typeof ApplyPatchTool>) {
     return "← Patched " + file.relativePath
   }
 
+  const pending = createMemo(() => {
+    const state = props.part.state
+    if (state.status === "pending" && state.received) return `Preparing patch… (${formatKB(state.received)})`
+    return "Preparing patch..."
+  })
+
   return (
     <Switch>
       <Match when={files().length > 0}>
@@ -2139,7 +2161,7 @@ function ApplyPatch(props: ToolProps<typeof ApplyPatchTool>) {
         </For>
       </Match>
       <Match when={true}>
-        <InlineTool icon="%" pending="Preparing patch..." complete={false} part={props.part}>
+        <InlineTool icon="%" pending={pending()} complete={false} part={props.part}>
           Patch
         </InlineTool>
       </Match>
@@ -2233,6 +2255,12 @@ function Diagnostics(props: { diagnostics?: Record<string, Record<string, any>[]
   )
 }
 
+function formatKB(bytes: number) {
+  if (bytes < 1024) return `${bytes}B`
+  if (bytes < 1048576) return `${Math.round(bytes / 1024)}KB`
+  return `${(bytes / 1048576).toFixed(1)}MB`
+}
+
 function normalizePath(input?: string) {
   if (!input) return ""
 

packages/opencode/src/session/message-v2.ts

@@ -268,6 +268,7 @@ export namespace MessageV2 {
       status: z.literal("pending"),
       input: z.record(z.string(), z.any()),
       raw: z.string(),
+      received: z.number().optional(),
     })
     .meta({
       ref: "ToolStatePending",

packages/opencode/src/session/processor.ts

@@ -34,6 +34,10 @@ export namespace SessionProcessor {
     let blocked = false
     let attempt = 0
     let needsCompaction = false
+    const deltas: Record<string, { text: string; bytes: number; path: string | undefined; last: number }> = {}
+    const PATH_RE = /"filePath"\s*:\s*"([^"\\]*(?:\\.[^"\\]*)*)"/
+    const THROTTLE_MS = 500
+    const THROTTLE_BYTES = 16384
 
     const result = {
       get message() {
@@ -125,10 +129,46 @@ export namespace SessionProcessor {
                   toolcalls[value.id] = part as MessageV2.ToolPart
                   break
 
-                case "tool-input-delta":
+                case "tool-input-delta": {
+                  const match = toolcalls[value.id]
+                  if (!match || match.state.status !== "pending") break
+                  const acc = deltas[value.id] ?? (deltas[value.id] = { text: "", bytes: 0, path: undefined, last: 0 })
+                  if (!acc.path && acc.text.length < 8192) acc.text += value.delta
+                  acc.bytes += Buffer.byteLength(value.delta, "utf8")
+                  if (!acc.path) {
+                    const m = PATH_RE.exec(acc.text)
+                    if (m) {
+                      try { acc.path = JSON.parse('"' + m[1] + '"') } catch { acc.path = m[1] }
+                      acc.text = ""
+                    }
+                  }
+                  const now = Date.now()
+                  const found = acc.path && !match.state.input.filePath
+                  const elapsed = now - acc.last >= THROTTLE_MS
+                  const grown = acc.bytes - (match.state.received ?? 0) >= THROTTLE_BYTES
+                  if (found || elapsed || grown) {
+                    acc.last = now
+                    try {
+                      const updated = await Session.updatePart({
+                        ...match,
+                        state: {
+                          status: "pending",
+                          input: acc.path ? { ...match.state.input, filePath: acc.path } : match.state.input,
+                          raw: match.state.raw,
+                          received: acc.bytes,
+                        },
+                      })
+                      toolcalls[value.id] = updated as MessageV2.ToolPart
+                    } catch (e: any) {
+                      if (e?.code === "SQLITE_CONSTRAINT_FOREIGNKEY") break
+                      throw e
+                    }
+                  }
                   break
+                }
 
                 case "tool-input-end":
+                  delete deltas[value.id]
                   break
 
                 case "tool-call": {
@@ -175,6 +215,7 @@ export namespace SessionProcessor {
                       })
                     }
                   }
+                  delete deltas[value.toolCallId]
                   break
                 }
                 case "tool-result": {

packages/opencode/src/tool/write.ts

@@ -19,8 +19,8 @@ const MAX_PROJECT_DIAGNOSTICS_FILES = 5
 export const WriteTool = Tool.define("write", {
   description: DESCRIPTION,
   parameters: z.object({
-    content: z.string().describe("The content to write to the file"),
     filePath: z.string().describe("The absolute path to the file to write (must be absolute, not relative)"),
+    content: z.string().describe("The content to write to the file"),
   }),
   async execute(params, ctx) {
     const filepath = path.isAbsolute(params.filePath) ? params.filePath : path.join(Instance.directory, params.filePath)

packages/sdk/js/src/v2/gen/types.gen.ts

@@ -365,6 +365,7 @@ export type ToolStatePending = {
     [key: string]: unknown
   }
   raw: string
+  received?: number
 }
 
 export type ToolStateRunning = {