Switch guides
New releases create pressure to move. These guides turn that into a controlled decision: when a cutover is justified, when to stay, and what to measure in a labelled pilot before production traffic moves.
Model API
Opus 5.5 is cheaper per token ($4/$20 vs $5/$25) and Anthropic's recommended starting point for many workloads, but it changes thinking and tool-use behaviour — a same-provider upgrade that still needs a regression pass.
Move new work to Opus 5.5 after a tool-use regression pass; keep Opus 5 pinned only where forced tool calls or a frozen validation baseline require it.
Read the decision guideModel API
GPT-6.1 Sol is OpenAI's newer Sol release at half GPT-5.6 Sol's $4/$20 promotional rate. It shares GPT-6 Sol's $2/$10 base rates, lowers cached input to $0.10, and has a separate model ID; re-test the exact API path before switching.
Pilot GPT-6.1 Sol as the current OpenAI Sol route; keep GPT-5.6 pinned where its frozen baseline or API behaviour remains necessary.
Read the decision guideModel API
DeepSeek retired V4-Flash on 2026-09-10. The legacy id temporarily routes to V4.1-Flash, so verify the first-party temporary reroute and any proxy/reseller behavior before assuming which model serves a request — this guide covers making that explicit.
Move to V4.1-Flash now on the hosted API; only self-hosted, frozen deployments have a reason to stay on V4-Flash weights.
Read the decision guideModel API
Historical comparison: use current model profiles for current rates, IDs and availability. A historical frontier-model comparison where workload fit, output pricing, and tool behaviour matter more than a universal winner. Update 2026-10-01: Claude Opus 5.5 and GPT-6.1 Sol are newer candidates; compare current profiles and validate both on the same tasks before routing.
Treat this as a workload experiment, not a leaderboard referendum — run it on Opus 5.5 and GPT-6.1 Sol, and use current model profiles for rates and access.
Read the decision guideModel API
Historical comparison: use current model profiles for current rates, IDs and availability. DeepSeek is the price-performance challenger; Luna is the simpler closed-provider path. Update 2026-09-26: DeepSeek retired V4-Flash on 2026-09-10 (the id routes to V4.1-Flash at $0.30/$1.20 peak) and OpenAI replaced GPT-5.6 Luna with GPT-6 Luna ($0.10/$0.50) on 2026-09-22 — the same pilot now applies to V4.1-Flash against GPT-6 Luna.
Use DeepSeek V4.1-Flash as a serious candidate, but validate it as a system rather than buying on the rate card — GPT-6 Luna is now cheaper per token, so the case for switching rests on quality and open weights.
Read the decision guideModel API
Historical comparison: use current model profiles for current rates, IDs and availability. Qwen3.8-Max is a hosted multimodal API; the Qwen3.8-2.4T-A95B checkpoint is a separate open-weight identity. For OpenAI, GPT-6.1 Sol is newer than GPT-6 Sol; compare current model profiles and test the exact API path before switching.
Qwen is worth a parallel evaluation; it is not yet a reason to rip out a stable Sol integration.
Read the decision guideCoding harness
Muse Code's terminal/CI workflow and Meta's multi-agent direction are the evaluation case; feature availability depends on the installed build and rollout. Claude Code is the established alternative.
Pilot Muse Code beside Claude Code; verify enabled workflows first, then measure productivity on your own repository tasks.
Read the decision guideCoding harness
Muse Code feature availability can vary by build and rollout. This is a workflow choice: stay in the editor for tight loops or hand larger objectives to a terminal agent.
Choose by task shape: Cursor for continuous editing, Muse Code for an experiment in delegated long-horizon work.
Read the decision guideCoding harness
Editor-native iteration versus terminal delegation — the switch only makes sense when your work pattern rewards staying in the file.
Switch toward Cursor when the editor loop is the bottleneck; stay on Claude Code when delegation and terminal control dominate.
Read the decision guideModel API
Historical comparison: use current model profiles for current rates, IDs and availability. Terra is OpenAI's balanced tier — the question is whether Sol's extra capability earns its premium on your actual tasks. Update 2026-10-01: GPT-6.1 Sol is the newer Sol release at the original GPT-6 Sol base price; check current profiles and compare it with Terra on your tasks.
Downshift to Terra when Sol is overspecified; keep Sol when the hardest tasks still fail on Terra.
Read the decision guideModel API
Historical comparison: use current model profiles for current rates, IDs and availability. 3.6 Flash remains in the catalog for teams already pinned to that id. For new Google Flash work, 3.8 Flash (2026-09-02) is the current coding/agent row; on the OpenAI side GPT-6 Luna ($0.10/$0.50) replaced GPT-5.6 Luna on 2026-09-22.
Keep 3.6 Flash only if you are pinned to that id; otherwise evaluate current Google Flash models, or GPT-6 Luna when text-only volume fits your workload and cost target.
Read the decision guideModel API
Historical comparison: use current model profiles for current rates, IDs and availability. 3.7 Flash is Google's efficiency-first Flash row (3.8 Flash is newer). Compare current list rates and workload results against GPT-6 Luna; do not reuse GPT-5.6 Luna benchmark rows as if they described its successor.
Pick 3.7 Flash when its extra input modalities or Google-managed route fit the workload; compare it with GPT-6 Luna on an identical task set and current list rates before switching.
Read the decision guideModel API
Historical comparison: use current model profiles for current rates, IDs and availability. The two budget flash workhorses of late 2026: Google's introductory-rate multimodal row against Z.ai's open-weight GLM release and a 1M context window.
GLM 5.3 Flash wins on listed price and open weights; 3.7 Flash wins on modality breadth, managed tooling, and published vendor evaluations. Pilot before cutover.
Read the decision guideCoding harness
Copilot offers inline assistance in supported editors; Cursor offers a different editor and agent workflow. Compare the current plan’s enabled features and your accepted-task results.
Move to Cursor when agentic editing is the bottleneck; stay on Copilot when inline assistance inside GitHub is sufficient.
Read the decision guide