feat(billing): bill Cursor executor usage via stream-json token parsing

Parse Cursor CLI usage from stream-json output and charge through billSessionUsage so subscription quota is consumed first and wallet overage applies when needed. Co-authored-by: Cursor <cursoragent@cursor.com>
2026-08-27 10:16:38 +08:00
parent 884e819f70
commit f95d766f69
9 changed files with 344 additions and 8 deletions
@@ -0,0 +1,54 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import {
+  buildCursorBillingTokenState,
+  extractCursorAgentDisplayText,
+  normalizeCursorAgentUsage,
+  parseCursorAgentUsage,
+} from './cursor-agent-usage.mjs';
+
+const SAMPLE_STREAM_JSON = [
+  '{"type":"system","subtype":"init","cwd":"/tmp","session_id":"abc","model":"Auto"}',
+  '{"type":"user","message":{"role":"user","content":[{"type":"text","text":"reply with exactly: ok"}]}}',
+  '{"type":"assistant","message":{"role":"assistant","content":[{"type":"text","text":"ok"}]}}',
+  '{"type":"result","subtype":"success","duration_ms":13064,"result":"ok","usage":{"inputTokens":7765,"outputTokens":64,"cacheReadTokens":5427,"cacheWriteTokens":0}}',
+].join('\n');
+
+test('parseCursorAgentUsage reads result usage from stream-json stdout', () => {
+  const usage = parseCursorAgentUsage(SAMPLE_STREAM_JSON);
+  assert.deepEqual(usage, {
+    inputTokens: 7765,
+    outputTokens: 64,
+    cacheReadTokens: 5427,
+    cacheWriteTokens: 0,
+  });
+});
+
+test('normalizeCursorAgentUsage includes cache write tokens in billable input', () => {
+  const usage = normalizeCursorAgentUsage({
+    inputTokens: 1000,
+    outputTokens: 200,
+    cacheWriteTokens: 300,
+  });
+  assert.deepEqual(usage, {
+    inputTokens: 1300,
+    outputTokens: 200,
+    cacheReadTokens: 0,
+    cacheWriteTokens: 300,
+  });
+});
+
+test('extractCursorAgentDisplayText prefers result text', () => {
+  assert.equal(extractCursorAgentDisplayText(SAMPLE_STREAM_JSON), 'ok');
+});
+
+test('buildCursorBillingTokenState accumulates on prior session billing', () => {
+  const tokenState = buildCursorBillingTokenState(
+    { inputTokens: 1000, outputTokens: 200 },
+    { lastInputTokens: 5000, lastOutputTokens: 800 },
+  );
+  assert.deepEqual(tokenState, {
+    accumulatedInputTokens: 6000,
+    accumulatedOutputTokens: 1000,
+  });
+});