Implementation Plan for ai/route/simulate Command (Related to #202)

[joelteply]

Overview

This issue documents the detailed implementation plan for the ai/route/simulate command as discussed in #202. The goal is to simulate AI routing decisions under various load conditions to test performance and reliability.

Code Skeleton (system/commands/ai/route/simulate.ts)

import { CommandParams, CommandResult } from '../base';
import * as Joi from 'joi';
import { hrtime } from 'process';

// Validation schema
const schema = Joi.object({
  iterations: Joi.number().integer().min(1).default(1000),
  concurrency: Joi.number().integer().min(1).max(100).default(10),
  scenario: Joi.string().valid('balanced', 'peak', 'failure').default('balanced'),
  model: Joi.string().default('default'),
});

// Main handler
export async function handler(params: CommandParams): Promise<CommandResult> {
  const validated = schema.validate(params);
  if (validated.error) throw new Error(validated.error.message);

  const { iterations, concurrency, scenario, model } = validated.value;

  // Mock request generation based on ai/model/list
  const requests = generateMockRequests(iterations, scenario, model);

  // Concurrent execution with timing
  const results = await runConcurrentSimulations(requests, concurrency);

  // Metrics calculation
  const metrics = calculateMetrics(results);

  return { success: true, metrics };
}

// Helper functions...
function generateMockRequests(iterations: number, scenario: string, model: string) {
  // Use ai/model/list to get real model data for mocking
  // ...
}

async function runConcurrentSimulations(requests: any[], concurrency: number) {
  // Use worker threads or Promise.allSettled for concurrency
  // Measure with hrtime.bigint() for ns precision
  // ...
}

function calculateMetrics(results: any[]) {
  // Sorted array for percentiles
  const latencies = results.map(r => Number(r.duration)).sort((a, b) => a - b);
  // Calculate p50, p90, p99 using array indices
  // Future: Integrate tdigest for streaming percentiles
  // ...
}

Key Decisions

• Timing: Use process.hrtime.bigint() for nanosecond precision in measurements.
• Metrics: Start with sorted arrays for efficient percentile calculations; plan to upgrade to tdigest for better streaming support.
• Mocking: Base request mocks on outputs from ai/model/list for realistic simulations.
• Validation: Joi schema ensures robust parameter handling.

Related to #202 - this serves as the actionable plan.