Migrate from OpenAI to Claude
End-to-end OpenAI to Anthropic migration — prompt port, eval parity, telemetry mapping, cost re-baselining, and a rollback plan that stays warm during the transition window.
The short version
Teams considering whether to migrate OpenAI to Claude rarely fail because Claude cannot do the job — they fail because the migration is run as a model swap when it is actually a port. NINtec runs OpenAI to Anthropic migration as an engineering programme: prompts get re-engineered (Claude rewards different prompt patterns), evals get re-baselined (Claude's strengths and weaknesses are not GPT's), telemetry gets re-mapped (token economics differ), and cost gets re-modelled (Claude is often cheaper per task, sometimes more expensive — never assume). Our LLM migration services run with both providers warm during the transition window, so the rollback path is real, not theoretical. The decision to switch OpenAI to Claude should rest on eval data from your workload, not benchmark anecdotes; our Discovery phase produces that data before any migration commitment.
What's in scope
Eval-Driven Migration Decision
Discovery produces head-to-head eval data on your specific workloads — task accuracy, latency distribution, cost per outcome, edge-case behaviour. Decision rests on data.
Prompt Re-Engineering
Claude rewards XML-structured prompts, explicit thinking blocks, and different few-shot patterns than GPT. Prompts are rewritten, not translated.
Eval Parity
Existing OpenAI evals are extended with Claude-specific test cases. Migration ships only when Claude meets or exceeds eval-bar.
Telemetry + Cost Mapping
Token-counting differences mapped, prompt-caching opportunities identified, cost dashboards updated to show before/after per workload.
Dual-Run + Graduated Cutover
Both providers stay warm during cutover. Workloads migrate one at a time, with rollback always one feature-flag flip away.
Tool Use Translation
Function calling translates to Claude's tool use with structural-difference handling — JSON schema mapping, parallel-call semantics, error semantics.
How NINtec delivers
Migration runs as four phases: Discovery (eval-driven decision, 2 weeks), Build (prompt re-engineering and eval parity, 4–8 weeks), Cutover (graduated workload migration with dual-run, 2–6 weeks), Steady-State (OpenAI dependency removal and cost-model finalisation, 2 weeks).
Read the full AI Engineering MethodHow we compare
| Dimension | Generic agency | Big consulting | NINtec |
|---|---|---|---|
| Claude engineer certification | Ad-hoc, unverified | Generic AI training | 4 internal tracks + Anthropic CCA path |
| Production deployments | 1–3 pilots | Case studies, few production | 11 platforms · 15 countries · live |
| Engagement response | Days–weeks | Weeks via BD layers | Architect on call in 48 hours |
| Listed-company posture | Private | Private partnership | NSE & BSE Main Board (NINSYS) |
| Regulated-industry coverage | Rare | Enterprise-grade | SOC 2 · ISO 27001 · HIPAA · GDPR · PCI DSS |
Where this lands first
300+
Certified Claude engineers
11
Platform products on Claude
6
Delivery phases — Claude in every one
48 hrs
Architect response time
How an engagement runs
Migration Discovery
2 weeks
Workload inventory, head-to-head eval, cost re-modelling, and a written migration decision document. If the data does not support migration, we say so.
Build + Eval Parity
4–8 weeks
Prompt re-engineering, eval suite extension, telemetry mapping. Both providers stay live; Claude runs alongside OpenAI for parity validation.
Graduated Cutover
2–6 weeks
Workload-by-workload cutover with feature flags. Rollback rehearsed before live cutover. Cost dashboards confirm projected savings.
Ready to talk to a Claude architect?
48-hour response from a senior architect. No BD-layer delay. The Readiness Assessment scopes the work and proposes named engineers.
Migrate from OpenAI to Claude — FAQ
Adjacent engagements
Claude API Integration Services
Targeting: claude api integration
Claude Development Services
Targeting: claude development services
Anthropic Claude Implementation Partner
Targeting: claude implementation partner
Managed Claude Services
Targeting: managed claude services
Claude AI Engineering Practice
Flagship — 300+ engineers, 11 platform products, 4 academy tracks
Talk to a Claude architect
Senior architect on the call in 48 hours. Walk away with a written assessment whether or not you engage.
Talk to a Claude Architect