[Init] Initial commit - NetMesh terminal manager

infrastructure/ai/harness/contextBudget.test.ts

@@ -0,0 +1,58 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import {
+  computeCompactionBuffer,
+  computeCompactionThreshold,
+  computeTotalInputTokens,
+  DEFAULT_MAX_OUTPUT_TOKENS,
+  shouldCompactByBudget,
+} from './contextBudget.ts';
+import type { ModelMessage } from 'ai';
+
+test('computeCompactionThreshold reserves output and buffer', () => {
+  const threshold = computeCompactionThreshold({
+    contextWindow: 128_000,
+    maxOutputTokens: 4096,
+  });
+  const buffer = computeCompactionBuffer(128_000, 4096);
+  assert.equal(threshold, 128_000 - 4096 - buffer - 150);
+  assert.ok(threshold < 128_000 * 0.85);
+});
+
+test('shouldCompactByBudget triggers when total input exceeds threshold', () => {
+  const messages: ModelMessage[] = [{ role: 'user', content: 'x'.repeat(400_000) }];
+  assert.equal(shouldCompactByBudget({
+    messages,
+    contextWindow: 128_000,
+    maxOutputTokens: 4096,
+    providerId: 'openai',
+  }), true);
+});
+
+test('computeTotalInputTokens includes system and tool names', () => {
+  const messages: ModelMessage[] = [{ role: 'user', content: 'hello' }];
+  const withExtras = computeTotalInputTokens({
+    messages,
+    systemPrompt: 'system prompt',
+    toolNames: ['terminal_execute', 'sftp_read'],
+    providerId: 'anthropic',
+  });
+  const base = computeTotalInputTokens({ messages, providerId: 'anthropic' });
+  assert.ok(withExtras > base);
+});
+
+test('computeCompactionThreshold keeps a reasonable threshold for small context windows', () => {
+  const threshold8k = computeCompactionThreshold({
+    contextWindow: 8_192,
+    maxOutputTokens: DEFAULT_MAX_OUTPUT_TOKENS,
+  });
+  assert.ok(threshold8k > 1_000);
+  assert.ok(threshold8k < 8_192 * 0.85);
+
+  const threshold4k = computeCompactionThreshold({
+    contextWindow: 4_096,
+    maxOutputTokens: DEFAULT_MAX_OUTPUT_TOKENS,
+  });
+  assert.ok(threshold4k > 500);
+  assert.ok(threshold4k < 4_096 * 0.85);
+});