feat: Added experimental TPS for model responses

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

@@ -69,6 +69,7 @@ import { Footer } from "./footer.tsx"
 import { usePromptRef } from "../../context/prompt"
 import { Filesystem } from "@/util/filesystem"
 import { DialogSubagent } from "./dialog-subagent.tsx"
+import { Flag } from "@/flag/flag.ts"
 
 addDefaultParsers(parsers.parsers)
 
@@ -1254,6 +1255,10 @@ function AssistantMessage(props: { message: AssistantMessage; parts: Part[]; las
   const sync = useSync()
   const messages = createMemo(() => sync.data.message[props.message.sessionID] ?? [])
 
+  function getParts(messageID: string) {
+    return sync.data.part[messageID] ?? []
+  }
+
   const final = createMemo(() => {
     return props.message.finish && !["tool-calls", "unknown"].includes(props.message.finish)
   })
@@ -1266,6 +1271,71 @@ function AssistantMessage(props: { message: AssistantMessage; parts: Part[]; las
     return props.message.time.completed - user.time.created
   })
 
+  const TPS = createMemo(() => {
+    if (!final()) return 0
+    if (!props.message.time.completed) return 0
+    if (!Flag.OPENCODE_EXPERIMENTAL_TPS) return 0
+
+    const assistantMessages : AssistantMessage[] = messages().filter((msg) => msg.role === "assistant" && msg.id !== props.message.id) as AssistantMessage[]
+
+    const allParts = assistantMessages.flatMap((msg) => getParts(msg.id))
+
+    const INVALID_REASONING_TEXTS = ["[REDACTED]", "", null, undefined] as const
+
+    // Filter for actual streaming parts (reasoning + text), exclude tool/step markers
+    const streamingParts = allParts.filter((part): part is TextPart | ReasoningPart => {
+      // Only text and reasoning parts have streaming time data
+      if (part.type !== "text" && part.type !== "reasoning") return false
+
+      // Skip parts without valid timestamps
+      if (!part.time?.start || !part.time?.end) return false
+
+      // Include text parts with content
+      if (part.type === "text" && (part.text?.trim().length ?? 0) > 0) return true
+
+      // Include reasoning parts with valid (non-empty) text
+      if (part.type === "reasoning" && !INVALID_REASONING_TEXTS.includes(part.text as any)) {
+        return true
+      }
+
+      return false
+    })
+
+    if (streamingParts.length === 0) return 0
+
+    // Sum individual part durations (excludes tool execution time between parts)
+    let totalStreamingTimeMs = 0
+    let hasValidReasoning = false
+
+    for (const part of streamingParts) {
+      totalStreamingTimeMs += part.time!.end! - part.time!.start!
+      if (part.type === "reasoning") {
+        hasValidReasoning = true
+      }
+    }
+
+    if (totalStreamingTimeMs === 0) return 0
+
+    const totals = assistantMessages.reduce(
+      (acc, m) => {
+        acc.output += m.tokens.output
+       if (hasValidReasoning) acc.reasoning += m.tokens.reasoning // Only count reasoning tokens if valid reasoning parts exists
+        return acc
+      },
+      { output: 0, reasoning: 0 },
+    )
+
+    const totalTokens = totals.reasoning + totals.output
+
+    if (totalTokens === 0) return 0
+
+    // Calculate tokens per second
+    const totalStreamingTimeSec = totalStreamingTimeMs / 1000
+    const tokensPerSecond = totalTokens / totalStreamingTimeSec
+
+    return Number(tokensPerSecond.toFixed(2))
+  })
+
   return (
     <>
       <For each={props.parts}>
@@ -1307,6 +1377,9 @@ function AssistantMessage(props: { message: AssistantMessage; parts: Part[]; las
               <Show when={duration()}>
                 <span style={{ fg: theme.textMuted }}> · {Locale.duration(duration())}</span>
               </Show>
+              <Show when={Flag.OPENCODE_EXPERIMENTAL_TPS && TPS()}>
+                <span style={{ fg: theme.textMuted }}> · {TPS()} tps</span>
+              </Show>
             </text>
           </box>
         </Match>

packages/opencode/src/flag/flag.ts

@@ -31,6 +31,7 @@ export namespace Flag {
   export const OPENCODE_EXPERIMENTAL_OXFMT = OPENCODE_EXPERIMENTAL || truthy("OPENCODE_EXPERIMENTAL_OXFMT")
   export const OPENCODE_EXPERIMENTAL_LSP_TY = truthy("OPENCODE_EXPERIMENTAL_LSP_TY")
   export const OPENCODE_EXPERIMENTAL_LSP_TOOL = OPENCODE_EXPERIMENTAL || truthy("OPENCODE_EXPERIMENTAL_LSP_TOOL")
+  export const OPENCODE_EXPERIMENTAL_TPS = OPENCODE_EXPERIMENTAL || truthy("OPENCODE_EXPERIMENTAL_TPS") 
 
   function truthy(key: string) {
     const value = process.env[key]?.toLowerCase()

packages/opencode/src/session/processor.ts

@@ -321,7 +321,7 @@ export namespace SessionProcessor {
                     )
                     currentText.text = textOutput.text
                     currentText.time = {
-                      start: Date.now(),
+                      start: currentText.time?.start ?? Date.now(), // No need to set start time here, it's already set in the text-start event
                       end: Date.now(),
                     }
                     if (value.providerMetadata) currentText.metadata = value.providerMetadata