Claude Opus 5.5 now available on AI Gateway

Vercel has added Claude Opus 5.5, Anthropic's latest flagship model, to its AI Gateway, giving developers a single managed endpoint through which to route production traffic to the updated model. The release marks Anthropic's most capable iteration of Opus yet, with the company describing the jump from Opus 5 to Opus 5.5 as a step-change rather than an incremental refinement.

This article covers what changed in the model itself, how Vercel's AI Gateway surfaces those changes, and the concrete steps a developer needs to take to start sending requests to Opus 5.5 today. It is aimed at teams already running Anthropic models in production and at engineers evaluating whether Opus 5.5 justifies a switch from their current setup.

What shipped in Claude Opus 5.5 now available on AI Gateway

Anthropic shipped Claude Opus 5.5 as the successor to Claude Opus 5, and Vercel simultaneously made it available through AI Gateway. AI Gateway is Vercel's proxy layer that sits between a developer's application and third-party model providers, handling request routing, observability, and rate-limit management without requiring changes to the calling application beyond a base-URL swap. The addition of Opus 5.5 means developers can access the new model without touching their Anthropic API credentials directly or managing a separate integration.

The model itself targets three capability areas that Anthropic identified as weak spots in Opus 5: agentic coding, long-running agent tasks, and knowledge work. Each of those workloads tends to produce multi-step, context-heavy request chains—exactly the environment where a proxy like AI Gateway earns its keep by centralising retries, caching, and logging across many parallel calls.

What improved in Claude Opus 5.5 now available on AI Gateway

Anthropic characterises Opus 5.5 as a step-change over its predecessor, with the largest deltas in the three workloads named at launch. Long-running agent tasks benefit from what Anthropic describes as better collaboration over long contexts, suggesting the model degrades more gracefully when a conversation or tool-call chain extends across many turns. Agentic coding improvements imply stronger instruction-following under multi-file or multi-repo conditions, where earlier Opus versions sometimes lost track of accumulated context.

Because the source announcement did not publish discrete benchmark scores, pricing tiers, or cache-hit ratios, the table below reflects the qualitative dimensions Anthropic disclosed rather than numeric deltas. Builders should run their own evals against representative workloads before committing to production.

What you gain from Claude Opus 5.5 now available on AI Gateway

Routing through AI Gateway means developers get Opus 5.5 without needing to re-instrument their observability stack. Every request that passes through the gateway is logged in Vercel's dashboard, giving teams per-model latency breakdowns and error rates out of the box. For organizations running cost-attribution workflows, AI Gateway also separates Opus 5.5 spend from other model traffic at the infrastructure level rather than relying on application-side tagging.

For teams building agents that run autonomously across many steps—code review pipelines, document processing chains, or multi-tool orchestration—the Opus 5.5 improvements to long-context collaboration reduce the risk of the model losing thread of earlier instructions. That matters most when an agent has already consumed several thousand tokens of prior exchanges by the time it reaches a decision point. Vercel's caching layer can offset some of the cost of those long-context calls, though developers should verify cache behaviour against their specific prompt structures.

How to get Claude Opus 5.5 now available on AI Gateway

To target Opus 5.5 through Vercel AI Gateway, update the model identifier in your existing AI Gateway configuration to claude-opus-5-5. If you are using the Vercel AI SDK, the change is a single string in your provider call:

import { anthropic } from "@ai-sdk/anthropic";
const model = anthropic("claude-opus-5-5");

For teams calling the gateway directly over HTTP with the OpenAI-compatible endpoint, update the model field in your request body:

curl https://ai-gateway.vercel.com/v1/chat/completions \
  -H "Authorization: Bearer $VERCEL_AI_GATEWAY_TOKEN" \
  -d '{"model": "anthropic/claude-opus-5-5", "messages": [...]}'

Verify the model name against Vercel's model catalogue before deploying, as the exact slug may carry a version suffix. No changes to base URL, authentication headers, or response parsing are required when switching from Opus 5 to Opus 5.5.

What to watch after Claude Opus 5.5 now available on AI Gateway

The two gaps to track are pricing and structured benchmark data. Anthropic did not publish token costs or context-window limits for Opus 5.5 at the time of the Vercel announcement, so teams budgeting for high-volume workloads should check Anthropic's pricing page directly and test against their actual traffic mix before rolling out widely. Cost per call for a step-change model often rises alongside capability, and long-context agentic tasks amplify token counts quickly.

The second thing to monitor is how Vercel extends AI Gateway's caching and observability tooling to account for the workloads Opus 5.5 is designed for. Long-running agent tasks generate unusual request patterns—high turn counts, interleaved tool calls, variable response lengths—that can behave unexpectedly under standard prompt-caching heuristics. Vercel has not yet published guidance specific to Opus 5.5 agent workflows, so builders should treat early production runs as instrumented pilots rather than stable deployments.