Claude Opus 4.7 Migration Guide

Claude Opus 4.7 is a mid-cycle capability update in the Claude Opus 4 generation. It is a drop-in replacement for Claude Opus 4.6 on the same slug prefix — switch the model string and you're done in most cases. This guide covers what changed and where you may want to adapt your prompts or parameters.

Model slug#

anthropic/claude-opus-4.7

Use this in the model field of any POST /v1/chat/completions request.

What changed from Claude Opus 4.6#

Improved instruction following#

Claude Opus 4.7 adheres more consistently to format instructions in the system prompt. If your Claude Opus 4.6 prompts used heavy repetition to enforce output format (e.g., "respond only with JSON, I said only JSON, no prose"), you can often simplify them. Test on your existing prompt set before removing guardrails.

Better multi-step reasoning#

Complex chains of reasoning — especially in code, math, and multi-document analysis — produce fewer errors in Claude Opus 4.7. The improvement is most visible in tasks that previously required chain-of-thought prompting to reach correct answers.

Tighter refusal calibration#

The model is less likely to refuse legitimate requests that contain sensitive keywords. If you had workarounds (rephrasing, system prompt overrides) specifically to get Claude Opus 4.6 to handle certain topics in your domain, test whether they are still necessary.

Extended context handling#

Claude Opus 4.7 performs better on tasks that reference material from deep in the context window. If your application stuffs large documents into the context and asks questions about them, expect improved retrieval accuracy without any prompt changes.

Parameters: no breaking changes#

All parameters honored by Claude Opus 4.6 work identically in Claude Opus 4.7:

• temperature, top_p, max_tokens — same range and behavior.
• Message roles system, user, assistant — unchanged.
• Vision inputs (content as an array with image_url parts) — unchanged.

Switching your code#

# Before
resp = client.chat.completions.create(
    model="anthropic/claude-opus-4.6",
    messages=messages,
)

# After — single line change
resp = client.chat.completions.create(
    model="anthropic/claude-opus-4.7",
    messages=messages,
)

// Before
const resp = await client.chat.completions.create({ model: "anthropic/claude-opus-4.6", messages });

// After
const resp = await client.chat.completions.create({ model: "anthropic/claude-opus-4.7", messages });

Testing checklist#

Before switching production traffic, run your existing evals against Claude Opus 4.7:

• Core task outputs match or improve versus Claude Opus 4.6.
• Output format (JSON, markdown, etc.) is consistent with expectations.
• Refusal rate on your normal inputs is the same or lower.
• Latency and token counts are within acceptable range (Claude Opus 4.7 may produce slightly longer outputs on reasoning tasks — check max_tokens headroom).
• DA cost per request is acceptable (check the model catalog for the current rate).

Rollback#

If you need to revert, change the model string back to anthropic/claude-opus-4.6. Both slugs remain available in the catalog simultaneously — OpenDunes does not remove model versions.

Pricing#

Claude Opus 4.7 is priced the same as Claude Opus 4.6 per million tokens today. Check the exact DA rates in the model catalog before estimating production costs.