fix(cli): unify MPP streaming status and improve response output

- Unify MPP streaming payment label from "MPP session:" to
  "Payment: ... MPP" matching the shared non-streaming format
- Add newline before MPP streaming status to separate from body
- Auto pretty-print JSON responses (2-space indent) on TTY for
  non-streaming application/json responses
- Honor --json flag to force pretty-printing even when piped
- Color-code HTTP status lines (green 2xx, yellow 3xx, red 4xx/5xx)

Author: tenequm

packages/x402-proxy/CHANGELOG.md

@@ -7,6 +7,17 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.8.3] - 2026-03-24
+
+### Added
+- JSON response pretty-printing: non-streaming `application/json` responses auto-formatted with 2-space indent on TTY
+- `--json` flag now works: forces JSON pretty-printing even when piped (non-TTY)
+- Color-coded HTTP status lines: green for 2xx, yellow for 3xx, red for 4xx/5xx
+
+### Fixed
+- MPP streaming payment label unified from `MPP session:` to `Payment: ... MPP` to match non-streaming format
+- MPP streaming status line now starts on a new line instead of appending to last JSON chunk
+
 ## [0.8.2] - 2026-03-24
 
 ### Fixed
@@ -219,7 +230,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `appendHistory` / `readHistory` / `calcSpend` - JSONL transaction history
 - Re-exports from `@x402/fetch`, `@x402/svm`, `@x402/evm`
 
-[Unreleased]: https://github.com/cascade-protocol/x402-proxy/compare/v0.8.2...HEAD
+[Unreleased]: https://github.com/cascade-protocol/x402-proxy/compare/v0.8.3...HEAD
+[0.8.3]: https://github.com/cascade-protocol/x402-proxy/compare/v0.8.2...v0.8.3
 [0.8.2]: https://github.com/cascade-protocol/x402-proxy/compare/v0.8.1...v0.8.2
 [0.8.1]: https://github.com/cascade-protocol/x402-proxy/compare/v0.8.0...v0.8.1
 [0.8.0]: https://github.com/cascade-protocol/x402-proxy/compare/v0.7.1...v0.8.0

packages/x402-proxy/package.json

@@ -1,6 +1,6 @@
 {
   "name": "x402-proxy",
-  "version": "0.8.2",
+  "version": "0.8.3",
   "description": "curl for x402 paid APIs. Auto-pays any endpoint on Base, Solana, and Tempo. Also works as an OpenClaw plugin.",
   "type": "module",
   "sideEffects": false,

packages/x402-proxy/src/commands/fetch.ts

@@ -21,6 +21,10 @@ import { getHistoryPath, isConfigured, loadConfig } from "../lib/config.js";
 import { dim, error, info, isTTY } from "../lib/output.js";
 import { buildX402Client, resolveWallet } from "../lib/resolve-wallet.js";
 
+function isStreamingResponse(res: Response): boolean {
+  return (res.headers.get("content-type") ?? "").includes("text/event-stream");
+}
+
 type FetchFlags = {
   method: string;
   body: string | undefined;
@@ -317,9 +321,10 @@ Examples:
 
           const elapsedMs = Date.now() - startMs;
           const spentAmount = mppPayment.amount ? Number(mppPayment.amount) : undefined;
+          if (isTTY()) process.stderr.write("\n");
           if (mppPayment && isTTY()) {
-            const spentStr = spentAmount != null ? `${formatAmount(spentAmount, "USDC")} ` : "";
-            info(`  MPP session: ${spentStr}(${displayNetwork(mppPayment.network)})`);
+            const mppAmount = spentAmount != null ? ` ${formatAmount(spentAmount, "USDC")}` : "";
+            info(`  Payment:${mppAmount} MPP (${displayNetwork(mppPayment.network)})`);
           }
           if (isTTY()) {
             dim(`  Streamed (${elapsedMs}ms)`);
@@ -570,7 +575,9 @@ Examples:
     }
 
     if (isTTY()) {
-      dim(`  ${response.status} ${response.statusText} (${elapsedMs}ms)`);
+      const statusText = `  ${response.status} ${response.statusText} (${elapsedMs}ms)`;
+      const colorFn = response.status < 300 ? pc.green : response.status < 400 ? pc.yellow : pc.red;
+      process.stderr.write(`${colorFn(statusText)}\n`);
     }
 
     // Record payment in history
@@ -606,22 +613,33 @@ Examples:
     }
 
     // Stream response body to stdout
+    const isJsonResponse = (response.headers.get("content-type") ?? "").includes(
+      "application/json",
+    );
+    const shouldPrettyPrint =
+      isJsonResponse && (flags.json || isTTY()) && !isStreamingResponse(response);
     if (response.body) {
-      const reader = response.body.getReader();
-      try {
-        while (true) {
-          const { done, value } = await reader.read();
-          if (done) break;
-          process.stdout.write(value);
+      if (shouldPrettyPrint) {
+        const text = await response.text();
+        try {
+          process.stdout.write(`${JSON.stringify(JSON.parse(text), null, 2)}\n`);
+        } catch {
+          process.stdout.write(text);
+          if (isTTY()) process.stdout.write("\n");
+        }
+      } else {
+        const reader = response.body.getReader();
+        try {
+          while (true) {
+            const { done, value } = await reader.read();
+            if (done) break;
+            process.stdout.write(value);
+          }
+        } finally {
+          reader.releaseLock();
         }
-      } finally {
-        reader.releaseLock();
+        if (isTTY()) process.stdout.write("\n");
       }
     }
-
-    // Trailing newline for TTY
-    if (isTTY() && response.body) {
-      process.stdout.write("\n");
-    }
   },
 });