New docs, recipes, benchmark analysis, and changelog entries from the MasterEngine developer hub. https://masterengine.dev/ 2026-09-29T00:00:00-05:00 MasterEngine AI https://masterengine.dev/openai-agents-api-guide.html 2026-09-29T00:00:00-05:00

OpenAI's Agents API (public beta since Sept 10, 2026) puts the Codex harness behind one API call. What it covers, what it leaves to you, and the four evaluation questions.

https://masterengine.dev/gpt-6-model-routing-guide.html 2026-09-29T00:00:00-05:00

Three GPT-6 tiers, 100x price spread, live since Sept 22. Route by stage: Luna for triage, Sol for reasoning and coding, Astra for architecture decisions.

https://masterengine.dev/openai-model-retirement-september-2026.html 2026-09-29T00:00:00-05:00

gpt-3.5-turbo-instruct, babbage-002, davinci-002, and gpt-3.5-turbo-1106 retired Sept 28 — traffic reroutes to gpt-5.6-terra. Find references, test, check costs.

https://masterengine.dev/managed-agents-vs-governed-missions.html 2026-09-29T00:00:00-05:00

Managed runtimes answer how the agent runs; they don't answer whether it should have acted. Five checks for any agent platform.

https://masterengine.dev/ai-coding-benchmarks-september-2026.html 2026-09-26T00:00:00-05:00

Claude Opus 5.5 leads the big three terminal-agent benchmarks, GPT-6 Astra answers on science and automation — every number attributed to the vendor that published it.

https://masterengine.dev/gpt-6-astra-vs-claude-opus-5-5.html 2026-09-26T00:00:00-05:00

The two models leading the September agent benchmarks, priced 2.5x apart. Opus 5.5 costs less and scores higher on most software-engineering benchmarks; Astra wins its own lanes.

https://masterengine.dev/ai-agent-cost-per-task.html 2026-09-26T00:00:00-05:00

You pay for completed tasks, not tokens. The math on why the cheapest token price is often not the cheapest completed task — for agent builders.

https://masterengine.dev/openai-devday-2026-what-to-expect.html 2026-09-26T00:00:00-05:00

DevDay lands September 29. The pre-event picture points to a security-focused GPT-6 Cyber preview and two efficiency models — Sol and Luna — priced for volume. What's confirmed, what's expected, and what it means for developers.

https://masterengine.dev/changelog.html#docs-v1-0 2026-09-25T00:00:00-05:00

The hub opens with four surfaces: home with a five-minute quickstart, the execution-chain docs, a six-recipe mission-spec library, and a versioned changelog. Mission-spec format v1 draft published, badged as evolving.