Claude Opus 5 vs Claude Sonnet 5 Comparison

// TypeScript — a specification-clear, hard verification task with Opus 5
import Anthropic from "@anthropic-ai/sdk";

const client = new Anthropic({ apiKey: process.env.ANTHROPIC_API_KEY });

async function runMigrationReview(diff: string) {
  const response = await client.messages.create({
    model: "claude-opus-5",
    max_tokens: 4096,
    // Thinking is already on in Opus 5; you steer its depth via
    // `output_config.effort` — "high" is the default, written explicitly here.
    output_config: { effort: "high" },
    messages: [
      {
        role: "user",
        content: `Review this Prisma migration diff adversarially:
try to disprove it on data-loss risk, irreversible
steps, and missing rollback scenarios.\n\n${diff}`,
      },
    ],
  });

  return response.content;
}

// In the Claude Code CLI, write the model explicitly when delegating:
// Agent({ prompt: "...", model: "claude-opus-5" })

// TypeScript — high-volume discovery/mechanical work with Sonnet 5
import Anthropic from "@anthropic-ai/sdk";

const client = new Anthropic({ apiKey: process.env.ANTHROPIC_API_KEY });

async function translateBatch(entries: string[]) {
  // For "clear finish-line" work like translation/i18n and file scanning,
  // Sonnet 5 delivers quality close to Opus 4.8 at 2.5x lower cost.
  const results = await Promise.all(
    entries.map((text) =>
      client.messages.create({
        model: "claude-sonnet-5",
        max_tokens: 1024,
        // Low effort = fewer tokens, faster response.
        output_config: { effort: "low" },
        messages: [
          {
            role: "user",
            content: `Translate this i18n key from TR to EN, preserve the tone:\n${text}`,
          },
        ],
      })
    )
  );

  return results.map((r) => r.content);
}

// In the Claude Code CLI, a subagent with no model specified inherits
// the main session's model — write the model explicitly for discovery work:
// Agent({ prompt: "scan the src/ directory", model: "claude-sonnet-5" })