This appears to be a part of a crackdown on third-party clients using Claude Code's credentials/subscriptions but not through Claude Code.
Not surprising as this type of credential reuse is always a gray area, but weird Anthropic deployed it on a Thursday night without any warning as the inevitable shitstorm would be very predictable.
I’m not surprised they closed the loophole, it always felt a little hacky using an Anthropic monthly sub as an API with a spoofed prompt (“You are Claude Code, Anthropic's official CLI for Claude”) with OpenCode.
Google will probably close off their Antigravity models to 3P tools as well.
Meanwhile, OpenAI co-signs https://github.com/steipete/oracle which lets you use your ChatGPT subscription to gain programmatic/agentic access to 5.2 Pro via automating browser access to the web frontend. Karpathy and other leaders have praised this feature on X.
If that is indeed so welcome, imagine what else you could script via their website to get around Codex rate limits or other such things.
After all what coud be so different about this than what browsers like Atlas do already
Anthro is having its Apple moment: too many customers means the company is always on the news, for better or worse.
When iPhones receive negative reviews it's not like only Apple screwed up; others did too, but they sell so much less than Apple that no one hears about them:
"Apple violated my privacy a tiny bit" makes the news;
"Xiaomi sold my fingerprint info to 3rd party vendors" doesn't.
Similarly, Anthropic is under heavy fire recently because frankly, Claude Code is the best coding agent out there, and it's not even close.
You're being downvoted because not only is Claude Code bad at what it does, none of the LLMs can actually code meaningfully, they can just statistically regurgitate other people's code without understanding what it does.
This is an unusual L for Anthropic. The unfortunate truth is that the engineering in opencode is so far ahead of Claude Code. Obviously, CC is a great tool, but that's more about the magic of the model than the engineering of the CLI.
The opencode team[^1][^2] built an entire custom TUI backend that supports a good subset of HTML/CSS and the TypeScript ecosystem (i.e. not tied to Opencode, a generic TUI renderer). Then, they built the product as a client/server, so you can use the agent part of it for whatever you want, separate from the TUI. And THEN, since they implemented the TUI as a generic client, they could also build a web view and desktop view over the same server.
It also doesn't flicker at 30 FPS whenever it spawns a subagent.
That's just the tip of the iceberg. There are so many QoL features in opencode that put CC to shame. Again, CC is a magical tool, but the actual nuts and bolts engineering of it is pretty damning for "LLMs will write all of our code soon". I'm sorry, but I'm a decent-systems-programmer-but-terminal-moron and I cranked out a raymarched 3D renderer in the terminal for a Claude Wrapped[^] in a weekend that...doesn't flicker. I don't mean that in a look-at-me way. I mean that in a "a mid-tier systems programmer isn't making these mistakes" kind of way.
Anyway, this is embarrassing for Anthropic. I get that opencode shouldn't have been authenticating this way. I'm not saying what they are doing is a rug pull, or immoral. But there's a reason people use this tool instead of your first party one. Maybe let those world class systems designers who created the runtime that powers opencode get their hands on your TUI before nicking something that is an objectively better product.
> Anyway, this is embarrassing for Anthropic. I get that opencode shouldn't have been authenticating this way. I'm not saying what they are doing is a rug pull, or immoral. But there's a reason people use this tool instead of your first party one. Maybe let those world class systems designers who created the runtime that powers opencode get their hands on your TUI before nicking something that is an objectively better product.
This is nothing new, they pulled Claude models from the Trae editor over "security concerns." It seems like Anthropic are too pearl-clutching in comparison to other companies, and it makes sense given they started in response to thinking OpenAI was not safety oriented enough.
Interesting that [1] is 30% zig as well as mostly typescript. That's a lot of native code for something that runs in a terminal (i.e. no graphical code required).
An engineer on my team who is working on TUI stuff said that avoiding the flicker is difficult without affecting the ability to copy/paste using the mouse (something to do with "alternate screen mode"). I haven't used OpenCode (yet) but Google does turn up some questions (and suggested workarounds) around copy/paste.
> A Claude Code subscription should not work with other software, I think this is totally fair
Why the hell not? What an L take - if I pay a subscription fee for an API, I should be able to use that API however I want. If they're forcing users to only consume their APIs with a proprietary piece of software, it really begs what's in that software that makes it valuable to them. Seems like there's something nefarious involved.
I've been (adding an OpenCode feature that allows the LLM to edit its own context)[1] and trying to debug an issue with the Anthropic API because I'm calling it with missing fields that it expects. I hope my multiple erronious API calls aren't what triggered this decision
I know this will sound strange, but SOTA model companies will eventually allow subscription based usage through third-party tools. For any usage whatsoever.
Models are pretty much democratized. I use Claude Code and opencode and I get more work done these days with GLM or Grok Code (using opencode). Z.ai (GLM) subscription is so worth it.
Also, mixing models, small and large ones, is the way to go. Different models from different providers. This is not like cloud infra where you need to plan the infra use. Models are pretty much text in, text out (let's say for text only models). The minor differences in API are easy to work with.
Cancelled my claude subscription over it. Opencode is miles ahead of any coding tools. Will stick to using it rather than claude.
Other models / other ways to access claude exists.
Ugh, well at least this was the nudge I needed to cancel my Claude Pro subscription... I've already had a bad taste in my mouth watching the rate limits on the plan get worse and worse since I first subscribed and I have a few other subscriptions to fall back on while I've been evaluating different options. I literally never use the regular Claude Chat web UI either, that's pretty much 100% Gemini since I get it via my Google One plan.
OpenCode makes me feel a lot better knowing that my workflow isn't completely dependent on single vendor lock-in, and I generally prefer the UX to Claude Code anyway.
This will piss a lot of people off, and seems like a strange move. I get that this was always a hack and against the ToS. But I've been paying Anthropic money every month to do exactly what I would have done with Claude Code, but in another harness that I like better. All they've achieved here is that I am no longer giving them money. Their per-token pricing is really expensive compared to OpenAI, and I like the results from the OpenAI models better too, they're just very slow.
Here's a good benchmark from the brokk team showing the performance per dollar, GPT-5.1 is around half the price of Opus 4.5 for the same performance, it just takes twice as long.
So as of today, my money is going to OpenAI instead of Anthropic. They probably don't care though, I suspect that not many users are sufficiently keen on alternative harnesses to make a difference to their finances. But by the same token (ha ha), why enforce this? I don't understand why it's so important to them that I'm using Claude Code instead of something else.
Presumably Claude Code is a loss leader to try to lock you into their ecosystem or at least get you to exclusive associate “AI” with “Claude”. So if it’s not achieving those goals, they’d prefer if you use OpenAI instead.
Unsure of the other competition, but I can vouch for synthetic.new's subscription for GLM (+ other open models). Note quite as accurate as Anthropic's models but good enough for basically everything I do.
This headline is misleading. EDIT: Or rather was, at it has now been edited to be accurate.
You can still bring your own Anthropic API key and use Claude in OpenCode.
What you can no longer do is reverse engineer undocumented Anthropic APIs and spoof being a Claude Code client to use an OAuth token from a subscription-based Anthropic account.
This really sucks for people who want a thriving competitive market of open source harnesses since BYOK API tokens mean paying a substantial premium to use anything but Anthropic's official clients.
But it's hard to say it's surprising or a scandal, or anything terribly different from what tons of other companies have done in the past. I'd personally advise people to expect everything about using frontier coding models becoming much more pay-to-play.
The ideal endgame is that AI lets us build tools that make it impossible to tell what application or device is using their APIs and everything becomes open to third party clients whether they like it or not.
155 comments
[ 4.7 ms ] story [ 98.1 ms ] threadNot surprising as this type of credential reuse is always a gray area, but weird Anthropic deployed it on a Thursday night without any warning as the inevitable shitstorm would be very predictable.
github:anomalyco/opencode?rev=5e0125b78c8da0917173d4bcd00f7a0050590c55 (a trivial patch that works for now)
Well let me tell you
https://github.com/anomalyco/opencode/blob/dev/packages/open...
You literally send your first message “you are Claude code”
The fact that this ever worked was insane.
Headline is more like anthropic vibes a bug and finally catches it.
Google will probably close off their Antigravity models to 3P tools as well.
If that is indeed so welcome, imagine what else you could script via their website to get around Codex rate limits or other such things.
After all what coud be so different about this than what browsers like Atlas do already
When iPhones receive negative reviews it's not like only Apple screwed up; others did too, but they sell so much less than Apple that no one hears about them:
Similarly, Anthropic is under heavy fire recently because frankly, Claude Code is the best coding agent out there, and it's not even close.Saying otherwise is just extreme copium.
The opencode team[^1][^2] built an entire custom TUI backend that supports a good subset of HTML/CSS and the TypeScript ecosystem (i.e. not tied to Opencode, a generic TUI renderer). Then, they built the product as a client/server, so you can use the agent part of it for whatever you want, separate from the TUI. And THEN, since they implemented the TUI as a generic client, they could also build a web view and desktop view over the same server.
It also doesn't flicker at 30 FPS whenever it spawns a subagent.
That's just the tip of the iceberg. There are so many QoL features in opencode that put CC to shame. Again, CC is a magical tool, but the actual nuts and bolts engineering of it is pretty damning for "LLMs will write all of our code soon". I'm sorry, but I'm a decent-systems-programmer-but-terminal-moron and I cranked out a raymarched 3D renderer in the terminal for a Claude Wrapped[^] in a weekend that...doesn't flicker. I don't mean that in a look-at-me way. I mean that in a "a mid-tier systems programmer isn't making these mistakes" kind of way.
Anyway, this is embarrassing for Anthropic. I get that opencode shouldn't have been authenticating this way. I'm not saying what they are doing is a rug pull, or immoral. But there's a reason people use this tool instead of your first party one. Maybe let those world class systems designers who created the runtime that powers opencode get their hands on your TUI before nicking something that is an objectively better product.
[^1] https://github.com/anomalyco/opentui
[^2] From my loose following of the development, not a monolith, and the person mostly responsible for the TUI framework is https://x.com/kmdrfx
[^3] https://spader.zone/wrapped/
If only Claude Code developers had access to a powerful LLM that would allow them to close the engineering gap. Oh, wait...
Why do you think opencode > CC? what are some productivity/practical implications?
This is nothing new, they pulled Claude models from the Trae editor over "security concerns." It seems like Anthropic are too pearl-clutching in comparison to other companies, and it makes sense given they started in response to thinking OpenAI was not safety oriented enough.
I'm curious, what made you think of that?
Not unusual, not for Anthropic.
I actually tried this several months back to do a regular API request using the CC subscription token and it gave the same error message
So this software must have been pretending to be Claude Code in order to get around that
A Claude Code subscription should not work with other software, I think this is totally fair
Why the hell not? What an L take - if I pay a subscription fee for an API, I should be able to use that API however I want. If they're forcing users to only consume their APIs with a proprietary piece of software, it really begs what's in that software that makes it valuable to them. Seems like there's something nefarious involved.
[1]: https://github.com/Vibecodelicious/opencode/tree/surgical_co...
Models are pretty much democratized. I use Claude Code and opencode and I get more work done these days with GLM or Grok Code (using opencode). Z.ai (GLM) subscription is so worth it.
Also, mixing models, small and large ones, is the way to go. Different models from different providers. This is not like cloud infra where you need to plan the infra use. Models are pretty much text in, text out (let's say for text only models). The minor differences in API are easy to work with.
I don't think I will renew Anthropic, the open models have reached an inflection point.
https://www.reddit.com/r/ChatGPTCoding/comments/1l2y2kh/anth...
https://github.com/anomalyco/opencode/issues/7410#issuecomme...
OpenCode makes me feel a lot better knowing that my workflow isn't completely dependent on single vendor lock-in, and I generally prefer the UX to Claude Code anyway.
Here's a good benchmark from the brokk team showing the performance per dollar, GPT-5.1 is around half the price of Opus 4.5 for the same performance, it just takes twice as long.
https://brokk.ai/power-ranking?dataset=openround&models=flas...
So as of today, my money is going to OpenAI instead of Anthropic. They probably don't care though, I suspect that not many users are sufficiently keen on alternative harnesses to make a difference to their finances. But by the same token (ha ha), why enforce this? I don't understand why it's so important to them that I'm using Claude Code instead of something else.
but time is also money. Personally if I could pay more money to get answers faster, I'd pay double.
I really don't understand why they thought this is a good idea. I mean I know why they wish to do this, but it's obviously not going to last.
The Agent SDK can piggyback on your existing Claude Code authentication
https://platform.claude.com/docs/en/agent-sdk/quickstart
You can still bring your own Anthropic API key and use Claude in OpenCode.
What you can no longer do is reverse engineer undocumented Anthropic APIs and spoof being a Claude Code client to use an OAuth token from a subscription-based Anthropic account.
This really sucks for people who want a thriving competitive market of open source harnesses since BYOK API tokens mean paying a substantial premium to use anything but Anthropic's official clients.
But it's hard to say it's surprising or a scandal, or anything terribly different from what tons of other companies have done in the past. I'd personally advise people to expect everything about using frontier coding models becoming much more pay-to-play.