LLM updates, June 2026: what shipped, and which ones your Mac agent can run

The June 2026 wave, with ship dates

Dates are the public ship dates I re-checked on June 22, 2026. The last column is the one the news pages leave out: how the model reaches a persistent agent loop on your Mac.

Opus 4.8 pricing and the dynamic-workflow preview are from Anthropic's release post. Nemotron 3 Ultra parameter counts, license, and the index score are from NVIDIA's model card and Artificial Analysis. MiniMax M3 figures (1M context, OSWorld-Verified 70.06%) are from MiniMax's launch coverage. Gemini 3.5 Flash pricing is from Google's I/O 2026 announcement.

The whole "can I run it" question is one Settings field

Fazm does not reimplement an agent. It runs the real Claude Code loop over the Agent Client Protocol, and ACP talks the Anthropic Messages API. That single fact is what makes the June 2026 wave reachable: anything you can put behind an Anthropic-compatible gateway becomes a backend the loop can address, with the persistence, forking, and no-compact behavior unchanged.

The control surface for that is a single text field in Settings, with the placeholder https://{your-proxy}:8766. What it does at launch time is narrower, and more careful, than "swap the model." It changes exactly one environment variable, and it deliberately keeps your real key off the wire.

# Raw Claude Code, talking to Anthropic
ANTHROPIC_BASE_URL=(unset -> Anthropic default)
ANTHROPIC_API_KEY=sk-ant-...your real key...
# Point this at a third-party proxy and your
# real key rides along on every request.

The right-hand column is not a marketing simplification. In ACPBridge.swift the custom-endpoint branch (around line 2417) validates the URL, then assigns it to env["ANTHROPIC_BASE_URL"], sets a FAZM_CUSTOM_API_ENDPOINT flag, and then does the part that matters for your account safety: it overwrites the key with a placeholder.

env["ANTHROPIC_BASE_URL"] = customEndpoint
env["FAZM_CUSTOM_API_ENDPOINT"] = "true"
// Never send Fazm's bundled Anthropic key to that proxy.
env["ANTHROPIC_API_KEY"] = "sk-fazm-custom-endpoint"

That placeholder, sk-fazm-custom-endpoint, is the anchor of this whole approach. The moment you route the agent through your own gateway, your real Claude Pro or Max credential stops being forwarded. Local Anthropic-compatible gateways accept any non-empty key, so the placeholder keeps the agent on the API-key path instead of accidentally kicking off a Claude OAuth flow against a server that is not Anthropic. You get the new model, your key stays home.

Why a typo here does not brick your chat

There is a sharp edge hidden in this design, and the code guards it explicitly. If a malformed value (a bare localhost:8766, a missing scheme, stray pasted text) reached ANTHROPIC_BASE_URL, the SDK would throw "Invalid URL" on every single query and the retry-with-resume path could swallow it into an empty turn, so you would see no error at all. The validator exists to make that impossible: it requires an http or https scheme and a non-empty host, and falls back to the default Anthropic endpoint otherwise. Here are the two log lines you actually get.

Wiring a June 2026 model into a persistent session

Concretely, here is the path for an open-weight drop like Nemotron 3 Ultra or MiniMax M3. The same four steps work for Gemini 3.5 Flash behind a shim, or for a corporate gateway.

What this does not do

A custom endpoint does not magically give a weaker open-weight model Claude Code's tool fluency. The agent loop still issues tool calls in the Anthropic format, and a model that is poor at structured tool use will fumble them no matter how clean your proxy is. The honest read of the June 2026 wave is that Opus 4.8 remains the strongest fit for the loop because the loop was built around it; the open-weight models are most interesting for local-first, privacy, or cost reasons, and for tasks where a 1M-token window or self-hosting matters more than the last few points of tool-following accuracy. The custom endpoint is the mechanism that lets you make that tradeoff yourself, per session, instead of being locked to one backend.

Common questions