Anthropic has two different products that are relevant here: the Claude API and Claude Code. The Claude API has usage based pricing. The more you use, the more you pay. With Claude Code, you can get a monthly subscription which gives you a fixed amount of usage. Comparing equivalent token generation between the Claude API and Claude Code, Claude Code with a subscription is much cheaper.
When it comes to third party products such as OpenClaw and OpenCode, Anthropic has made it clear those products should be using the Claude API and not the internal Claude Code APIs. OpenClaw and OpenCode have both been using the internal Claude Code APIs as when a user has a Claude Code subscription, the internal Claude Code API gives you tokens at a much cheaper rate than the Claude API. Presumably Anthropic makes Claude Code cheaper than the Claude API because they are willing to give users a discount for them to use Claude Code vs a competing product such as OpenCode.
It looks like until recently OpenCode tried to get around Anthropic's requirements by offering "plugins" in OpenCode that would allow users to use their Claude Code subscription in OpenCode. This PR mentions as much at[0][1]:
> There are plugins that allow you to use your Claude Pro/Max models with OpenCode. Anthropic explicitly prohibits this.
> Previous versions of OpenCode came bundled with these plugins but that is no longer the case as of 1.3.0
This PR seems to be in response to Anthropic threatening OpenCode with legal action if they keep using the internal Claude Code APIs.
[0] https://github.com/anomalyco/opencode/pull/18186/changes#diff-b5d5affc6941bf7bb19805cc8f556cd1b9ae73ffd99e520120700536b166f8c0L310
[1] https://github.com/anomalyco/opencode/pull/18186/changes#diff-b5d5affc6941bf7bb19805cc8f556cd1b9ae73ffd99e520120700536b166f8c0R321I think we can attribute a bunch of consternation here to drift between assumed and actual licensing terms.
The actual licensing terms for Claude Code expressly prohibit use of the product outside of the Claude Code harness. If you want Opus outside of CC, the API is available for your use anytime.
Some percentage of the community seems to assume their Claude Code subscription licenses allow free usage of CC across any product surface - including competing products like OpenCode. While this is a great way to save on API costs, the assumption is incorrect. In fact, it is *so* incorrect that Anthropic has encoded their licensing terms into their Terms of Service, and a result can take legal action against any violating parties.
We can have separate discussions about Anthropic’s use of the Common Crawl in pre-training, or whether foundation labs adhere to robots.txt conventions. But those don’t directly impact Anthropic’s right to bring litigation.
——
Outside of that I think angry users have their own stated preferences v revealed preferences here. They claim they want Opus on their terms, and Anthropic’s actions infringe on their user rights.
Angry folks: Opus is right there! You just need an API key! The reality is you want Opus in your devtools of choice at discounted rates. You could at least be honest about your consternation
I think that’s a bit more nuanced. The actual „product” is not the harness, which is free anyway, but the Claude subscription. In any scenario, that’s what the customer continues to pay for. I understand why Anthropic is doing that, but I feel no need to defend it. Just like I understand why Apple limits your app choices to AppStore, but I’m not going to go out of my way to defend their decision.
Some of us don't care for Anthropic's "right to bring litigation" anymore than we care about some scumbag patent troll company doing things "within their legal rights".
We care for the morality of its conduct, the openess of its products, and the environment it creates.
No, the two relevant products are Claude API vs Claude subscription. There's no "Claude Code subscription". There's just a subscription for all Claude services at once.
Basically, the concept of Claude-Code having its own API tier holds.
Like if any agent can use claude models then it exposes them to distillation risk. Where data gathered from millions of such agent usage can easily be used to train a model, making their model superiority subpar
Second thing is, to improve their own coding model, you need predictable input.
If input to their model is all over the place (using different harnesses adds additional entropy to data) then it's hard to improve the model along 1 axis.
Cache is money saver in computing. Their own client might be lot better at caches than any other agent so they do not want to lose money yet end up with disgrunted customer that claude isn't working as good
And also, if a user can simply switch model in an agent. Then what moat does anthropic have? Claude code will not include other companys models and thus will allow them to make their claude code more "complex" with time so the workflows are ingrained in users psyche to the point using anything else becomes very difficult and user quickly returns to claude code
This idea that companies should be allowed to lock down their products just so they can have moats, is how we ended up with printer ink being more expensive than crude oil or champagne.
I’d bet a reasonable amount that this could be the case. They are very well incentivized to maximize cache use when it’s basically not pay per token.
In other words, you pay $$ for a subscription, but Anthropic has the gal to tell you what client to use with it.
But to use their product,you have to go through the non-human-friendly API route, or else it's against the rules and Anthropic will sic their legal team onto you...
Something about this reasoning seems brittle. Specially in a world of Agentic tools
Ok
Like, in any event, I seriously get the feeling that Anthropic doesn't just not care about their users, but actively dislikes them. Like, they must be losing so much money on each Claude Code subscriber that if a million people all said "we're switching" they just wouldn't care. I get this vibe even from watching videos of people working on the Antrhopic team; like they all think they're Gods above mere mortals, serving some higher purpose, and nothing matters to them except Building the Machine God.
OpenCode is awesome. Claude Code is nothing special at all. Last month I switched to just using OpenCode with a Codex $200/mo subscription, and that's been great. Let the weirdos at Anthropic do what weirdos do, and hopefully one day their name is never mentioned again in polite society.
There was GMailFS[0] and Gmail Drive[1] - this is before S3, dropbox, and a time where web hosting would give you ~10MB or so of space.
Google updated their ToS and shut down accounts using their service in ways they weren't intended via these apps - because obviously the 1GB of storage was a loss-leader into Google's ecosystem (and it worked)
Same thing today - "unauthorized" third parties taking advantage of a loss-leading[2] deal - complete with similar trademark violations to boot[3].
Google have more cash to burn in the AI race so can be more forgiving today in how their codex plans are used. Anthropic are still a private company and can't.
[0] https://handwiki.org/wiki/GmailFS
[1] https://techcrunch.com/2005/07/31/profile-gmail-drive/
[2] it's a big q just how large a loss leader the max plans are considering a fixed harness, prompt caching etc. but point still stands. you're getting up to $5k of RRP tokens for $200
[3] Clawd Bot -> OpenClaw
Even despite the larger cash pile to burn, Google is in the middle of their own controversy around what many feel is a rug-pull around how Gemini "AI credits" work and are priced.
See:
https://www.theregister.com/2026/03/12/users_protest_as_goog...
https://old.reddit.com/r/google_antigravity/comments/1rv4cec...
etc
Hemorrhaging money more than Anthropic?
Theory 1: the internet has been fully strip mined for all content and is now dead. See that graph of StackOverflow questions dropping off a cliff to zero. Nothing much worthwhile is being added.
Theory 2: they are all unethical as fuck and definitely learning off your data. You would be insane not to - theory 1 means all your free training data is gone, but all that corporate data is fresh, ripe and covers many domains that the amateurs on the internet never filled. You have to launder it some way of course, but it's definitely happening.
Theory 3: winner takes all. I don't care for "Claude" and your wishy-washy ethics performance. ChudAI has a better model and harness? I'm gone this evening.
Having all the users, even if they are exploiting you for cheap compute with their own harness, is essential.
I don't think there's anything really to it past that.
Can you explain what you mean by this?
2. All 'all-you-can-eat' plans everywhere comes with clause. Whether it is lunch at a restaurant or it is token-proxy-providers who might think of reselling Max plan to individuals at 20% markup.
> Let the weirdos at Anthropic do what weirdos do, and hopefully one day their name is never mentioned again in polite society.
Woof, that is a bit harsh... :) OpenAI will also face the same problem. They are doing it right now because they need to stand out in some way.
I do fully expect the limits on these subscriptions to be brought down. But that's not the problem people have with Anthropic today, nor the problem we'd have with OpenAI when they have to eventually do it. That's just the way of things.
The problem is: These actions by Anthropic scream: "Our internal unit economics are going nuclear and we need to do anything we can to regain control."
Low-key: I think the DoW situation was an inflection point for their usage internally. It spiked up hard after that. Dario spent all of 2025 being told "you're not investing enough into compute", but really didn't listen because he wanted to be "responsible" or whatever, and now they're shopping to every provider trying to find compute and are being told that there isn't any.
This is about controlling user behaviour, resisting standardisation efforts, to keep subscribers hooked to their models. If they keep their users on claude code, they don't have to adapt to evolving harness standards when shown increased usage across different harnesses. They will try to keep everything on their terms, on their poor quality of engineering, and the users accustomed to claude behaviour will be left with no quick way to switch to other models.
This strategy will keep working as long as they own a top tier frontier model with enough marketing hype behind it to blind unsophisticated users.
Can't collect telemetry from applications you don't control.
So it hard for them to control and understand the costs of subscriptions if people are using them on different hardnesses that do things that they have no control over.
You're looking at it completely wrong. Claude Code is Anthropic's flagship product, not the API. They want to attract as many users as possible to Claude Code and lock them into their ecosystem, so they can squeeze them later. All of their questionable actions surrounding Claude Code and its subscription are ultimately in service of this goal.
The subscription isn't some kind of charity, it exists specifically because they know the average user isn't willing to pay the exorbitant API prices to vibe code their groundbreaking new B2B SaaS idea, but they want to capture that market share anyway, because it's the core of their long-term strategy. The subscription arose from that: it's a form of predatory pricing designed to attract as many users as possible while they still have VC money to burn.
Once that runs out and the time comes to IPO and start making real profits, they are going to increase the price drastically, and what's where the lock-in comes into play. If everyone is using some open-source alternative that natively supports every other provider on earth, they will be far less likely to continue paying for Claude specifically instead of just switching to a competitor. Not to mention, they'd also lose out on the free advertising from things like CLAUDE.md and the commit co-signing (because that's all those things are, the only reason Claude Code doesn't support AGENTS.md is because CLAUDE.md serves as an advertisement in public repositories).
> like they all think they're Gods above mere mortals, serving some higher purpose, and nothing matters to them except Building the Machine God.
This is all just part of their marketing strategy, and you shouldn't read too much into it.
They are still losing billions of dollars and will do anything to keep people hooked onto the API and will litigate against their own customers.
They will even lobby against open-weight models which is their biggest threat and want to make them illegal to run in the US just for them to succeed.
Anthropic are not your friends and want you to become addicted / over-reliant on Claude Code (hence the free $20 spins at the roulette until March, 27 2026) and charging others on their overpriced API.
Paying customers of Claude Code don’t receive a free-use license for any desired application. They’re paying to use Claude Code. Anthropic can take steps to litigate usage outside of those terms, even if customers find that fact really annoying.
I have noticed odd behavior when choosing a model, it automatically switches after sometime. Some tasks do not require lots of power, so when I select Haiku, few prompts later, I see Sonnet popping up in the cost/spending. Happened few times.
The times it works, it works well for the company at great cost to society.
Imagine the world we'd have if comcast got to control your web browsing experience.
If ISPs got started today, they'd sell the open web at API prices that no one can afford. Then sell the ISP's lock-in 'internet' for a low monthly fee.
My question is why people who don't want comcast's internet think other vertical integrated lock-in is fine.
Our markets game only works for the benefit of society if we have fair markets.
VC-backed loss-leader dumping to starve competition model breaks the game.
We'll know for sure when they add full OpenClaw-like features to Claude Code like remote channels & heartbeat support. Both are partially implemented already.
Off topic, but there is something like that: photopea, it's free and it's good enough for my use cases (I need it once a year maybe).
For all of these reasons, currently, the meta is ChatGPT subscription on Codex or OpenCode. But, again, these things change every few weeks.
I don't think this is as clean-cut as just saying "Anthropic is in their rights" etc. Of course, they are, to whatever degree they are; the bigger problem is that you've got $100/mo and $200/mo Claude subscriptions who are actively saying "the $20/mo Codex subscription is better in every way", possibly because of these thinking budget/routing changes people suspect have happened this month. In other words: Anthropic is at-capacity after the DoW incident, they need to load shed, and they've chosen to harm their high-paying power users and Enterprise over just temporarily slowing growth a bit by hurting the $20/mo plan. And, frankly, they might be right: because for every $200/mo user that jumps over to ChatGPT, half of them will be back once Anthropic can scale capacity, and if they can gain 20x $20/mo users who only use half their sub, that's a win.
With 3rd party, designers have not incentive to be token consumption conscious.
Gemini has a 1M token context, flash can be used for free via the web interface, can't paste more than handful thousands token.
How? If I used open code I'd hope it to not eat tokens unnecessarily so my subscription quota lasts longer.
I add 'only do this if...' to every single skill I write. It's a bit of voodoo-style wishful thinking, I admit.
It's weird, my experience is the exact opposite: OpenCode had the weirdest issue of interpreting C:\Users\some-user\Documents\Projects\... as a bunch of escaped characters without \ and created some trash files even with Anthropic models. Before then, OpenCode had the issue of me copying multiple lines of text into it from clipboard somehow quitting the program (crashing?) and then making every following line (of text, notes etc.) be passed to the shell directly. Happened in both Terminal app and also Git Bash on Windows. It might just be that Windows is a shit OS, but Claude Code doesn't really seem to exhibit those problems (and neither does Codex, in their defense). I hope OpenCode has fixed at least some of those since.
> Let the weirdos at Anthropic do what weirdos do, and hopefully one day their name is never mentioned again in polite society.
What an odd thing to say. Maybe I'm out of the loop about some drama (aside from Anthropic having a bit of a spine in regards to govt. while being otherwise flawed still), but pretty happy with my Max subscription, they even fixed the Code GUI mode in their Electron app recently, it finally feels usable and I don't just need to juggle 4 terminal sessions.
OpenAI is allowing it as a PR stunt and because they have seemingly unlimited cash they can throw at user growth.
The sibling reply given by strictnein is very likely a factor.
Sorry, what is pi and how are you using it with ChatGPT for agentic coding?
The only sticky part that will remain will be the UX of particular harness and post-training flavors.
I like Anthropic’s models better than OpenCode + GPT/Gemini.
AI companies would have to be one of the worst for actually caring about their user's health and wellbeing.
Closed ecosystem like Apple. They want you to use their tools, not someone else's.
You are given a loss leader product under certain terms for a very cheap price. The ONLY condition is that you respect the terms.
Instead of doing that you go off on this rant about how you shouldn't have to respect the terms and the company is evil for imposing terms at all!
The Claude API is RIGHT THERE if you don't want to use the loss leader. Where is this entitlement coming from!?
Sure Codex lets you do this for now, but VC money is finite and people won't let you abuse their free loss leaders forever.
Previously discussed I think:
Anthropic Explicitly Blocking OpenCode (173 points, 157 comments)
Anthropic sells a service that bundles server and client. They are not wild about people taking their server part and using their own clients because the business model relies on both client behaviors (Claude code does a lot of work to achieve > 95% cache hit rates; third party clients likely don’t) and flywheel of usage data.
If Microsoft went after third party clients that emulated M365 and used their backend, would that also “make friends” in open source somehow?
Typically services that try to gatekeep standard http don't get very far with the kind of people that like to modify their software.
That's really all there is to it. It has nothing to do with open or closed source.
Their documentation, cli, SDKs, TOS, their public stance - have major contradictions and are subject to so much interpretation that you can't really figure out what's allowed and what's not.
Opencode allowed? No
Custom agentic harnesses allowed? Yes
Opencode is a custom agentic harness? Yes, but not allowed
Which agentic harness is allowed? Can I use a custom agentic harness I develop - say, tmux that runs claude code? We don't know, but you'll know if we ban you
Anthropic stance has not been consistent. There are even now still articles by them telling users about unattended use like in CI which would now be considered TOS
Their stance has just been clear for a year now, even if they've changed their mind in comparison to the introduction of the sub, which significantly predates Claude code
It’ll be interesting to see if companies get tricked. I think it’s inevitable that it goes like MySQL/Postgres, where the open tools gets way better
IIRC it was called Clawdbot when Anthropic complained. IANAL but I believe the holder of a trademark is obligated to defend it against infringement. Hard to say that Clawdbot was not potentially infringing, given its purpose. It's not clear how much leeway Anthropic had given his initial choice of name.
"Safety" is just complete control for them.
The thing is OpenCode IS a great product, I'm not sure it's "superior", but unfortunately the way things are evolving where the model + harness pairing is so important, it does seem like they are in a similar position to Cursor (and do not have the resources to try to pivot into developing their own foundational model).
OpenCode lets people take the Claude-Code-only-API-Key, and lets them use it in a different harness. Anthropic's preferred way for such interaction is getting a different, Claude API key (and not Claude Code SDK API key).
---
A rough analogy might be something like getting subsidized drinks from a cafe, provided you sit there a eat food. What if someone says, go to the cafe and get free drink and come sit over at our cafe and order food. It is a loose analogy, but you get the idea.
Is this actually the case though? Because I can't imagine what kind of hardware they're running to have costs per 1M tokens be above like $3.
hint: {
opencode: "recommended",
-anthropic: "API key",
openai: "ChatGPT Plus/Pro or API key",
}[x.id],
I don't necessarily see this as an evil action. It doesn't inhibit open source, it sets terms of service and practice boundaries.
Granted this is a wildly unpopular approach, worse has happened in the OSS world...
I don’t believe Anthropic will win this battle.
I just want to use the tools in a way and customized way that I want, Anthropic not allowing me to me to do that forced me to use the codex models, thanks for that I’m very happy with the results. I’m cheering for OpenAI
So if CC has an SDK, why doesn't OC just use the SDK? I assume there's some functional reason why it doesn't perform to their needs? Maybe it's not low level enough? I'm unfamiliar with what sort of functionality a harness needs.
It makes me nervous as i'm using the CC SDK for my own wrapper though. Hypothetically what i'm doing is no different than embedding CC into an IDE.. though. Fingers crossed.
Users will say this-or-that about choice etc etc. It’s about subsidized tokens. Otherwise th users (and OpenCode) would have stopped pushing the workarounds months ago.
Yes, i completely agree - which was my question. To my understanding OC was using CC API directly instead of using the SDK. My question is, why? Does the SDK prevent some functionality they needed?
This would essentially take us back to what online services were 20 years ago, by outlawing a business model that relies on providers controlling stuff on users' devices. What's on the server is the company's business, what's on the client is the user's, and the boundary is clear. On the one hand, services that would persist would likely no longer have free tiers (which would essentially mean free lunch for customers); since it's a commercial service run by a company that has costs, it's just normal to pay for it as a user, there's no free beer anywhere. On the other hand, by paying for something, you'd get that thing and nothing else, as there's always going to be a client that doesn't leak data not necessary for the service to perform whatever you paid for, or impose arbitrary restrictions on its use. If any, these need to be server-side.
Opencode just works faster and I prefer the UX.
Are you delegating substantial work like planning and executing refactors, or more at single-line and function-level work?
It originally had support for copying over your Claude subscription token and calling the same backend APIs as Claude Code, which meant you could use OpenCode with your Claude Pro/Max plans, but Anthropic came out and said that the plans were only meant for first-party clients, and everyone else should be using per-token billing.
Now OpenCode is removing this option from their product, it seems because of legal threats from Anthropic.
You where not allowed to use your ClaudeCode subscription with other tool then ClaudeCode. I'm not sure if this is what got removed or if there is more too it.
So they're being obtuse about it for some reason, but if you want an economically sustainable model for AI companies they have to have some kind of optimization for the otherwise ridiculously discounted subscriptions. They sell subscriptions at the same rate and quotas to enterprise now, minus the $200 tier, so this isn't just consumer marketing being subsidized by b2b revenue.
Whether they're making money or just losing less, you can only get those kind of cache optimizations when you have a fixed client.
But what is the argument here? "OpenCode facilitates the users of their opensource tool to misuse another app they have installed"?
I guess anything goes with ip law really. Its all about flexing lawyer power and willingness to drown opponents in legal costs.
Maybe if you dont want people to misuse your sub dont ship the ability to do so in the app that users actually installed on their machines?
This is the same as all the alternative youtube clients. Just play the cat and mouse game Anthropic
In the end, a business gets to decide how and when to strategically subsidize their users.
But right now I'm not so sure anymore, if gpt-5.4 got actually better than opus-4.6 recently.
As much as it kills the living shit out of me to say this... Apple M5 Ultra will probably mean for a lot of us that we wont need openai or anthropic for coding llms anymore
While SOC is definitely the future or local AI, even if you get an M5 that's jacked to the tits, you still won't be able to store the entire model in unified memory on top of the OS and whatever other applications you have running. 128GB is the upper limit for unified memory on the M5, which on paper could support a model like gpt-oss:120b but still with a nerfed context size and quantised at that. Furthermore, the cost of a maxed out Macbook Pro M5 Max is between $8-10k depending on your storage option, screen size etc., so we can safely assume that the M5 Ultra will be even more. There's also no guarantee that the Ultra will offer double the amount of unified memory, it may only offer more cores but cores aren't the current bottleneck for local AI, memory is.
If you consider what you'd be paying above and beyond your requirements barring local AI, it would be adding $5-6k to the price tag at a minimum. That equates to 5 years worth of a Claude Code subscription! Even if you shouldered that cost with your NFT fortunes you likely wouldn't achieve performance parity with CC.
I'm equally as excited as you are about the future for local AI and I am actively working in this space everyday to improve it but we're still a long way off from being able to match model size, context size, token/sec, TTFB etc. A single H100 is so OP, so hosting thousands in a data centre it's expected that it should remain unrivalled.
The area where I'm having success with local AI is by pairing local models with other supportive technologies like databases and the like to compensate for smaller context size. There are still many in roads to be made in this area and that bodes well for the future of local AI as models become more efficient and sophisticated.
The people mad about this feel they are entitled to the heavily subsidized usage in any context they want, not in the context explicitly allowed by the subsidizer.
It's kind of like a new restaurant started handing out coupons for "90% off", wanting to attract diners to the restaurant, customers started coming in and ordering bulk meals then immediately packaging them in tupperware containers and taking it home (violating the spirit of the arrangement, even if not the letter of the arrangement), so the restaurant changed the terms on the discount to say "limited to in-store consumption only, not eligible for take-home meals", and instead of still being grateful that they're getting food for 90% off, the cheapskate customers are getting angry that they're no longer allowed to exploit the massive subsidy however they want.
Anthropic has every right to place rules around their generous subsidization of the Claude subscription plans, which give limits of ~8-12x as many tokens as you'd get for the same expenditure in the PAYG API.
That said, demanding an open source repo remove information that Anthropic openly publishes and distributes for free (the prompt) is a bit odd...
This move is anti-competitive and Anthropic knows it. They're hurriedly trying to lock the gates and lay landmines behind everyone after a massive surge of new subscribers so that they're stuck using Claude Code. They see it as vital to their survival to not just to be the gas pump for tokens, they need to control the platform.
No it hasn't, because the argument is completely correct, and the people mad about it are mad they can't have unlimited usage instead of paying the token API prices.
> This move is anti-competitive and Anthropic knows it.
No it isn't, that's not what "anti-competitive" means, and no court in the world would label it as such. You can't go flailing around looking for legal jargon to attach to behavior just because you don't like it.
I mean, OpenCode is the one changing their app here. So it kinda seems like it's actually everyone else's problem.
There’s a reason 5% of GitHub commits are from Claude code and no other provider is above 0.1%… it’s quality, but it’s also subsidy.
That clarified: yes, every major lab is losing money on full utilization of their inference subscription plans. The API prices are what the business has determined they need to achieve profitability, and are not reflective of actual costs as you point out, but the discounts vs API pricing can get pretty extreme. Some users report 50x+ (98%+) discounts on the $100/mo Max subscription plans vs PAYG API pricing¹. Even the skeptical, contrarian takes that focus on cost to the business will tell you that, yes, Anthropic is losing money on those subscriptions, even using generously low estimates on costs².
¹ https://www.ksred.com/claude-code-pricing-guide-which-plan-a...
² https://martinalderson.com/posts/no-it-doesnt-cost-anthropic...
Only Anthropic knows their inference costs. And do we _really_ think they’re losing money? Hahaha
Opencode to a lot of people is a nicer and more feature rich harness than CC, it doesn’t consume any more tokens than CC, and if it did, the bounds of how many tokens each account is allowed to use is tied to the users payment and rate limits.
Today they nuked my account again. I can only assume it was because I had the gall to find so much value in their product that even after they banned me once, I still wanted to give them money!
I've been around this planet a long time and I have never encountered a tech company as hostile to their users as Anthropic. And that includes Microsoft back in the 90's & 00's.
I really hope they change their ways. But for now, I'm done with them. I'll take my business elsewhere.
I miss the days when open source was a way to get your product in the developers hands and build trust. Stuff like this shows that the tide has shifted to primary focus on shareholders and potential hold on patents and trademarks.
Me too. I also miss the days when I was proud of my little open source projects. Now I just regret donating fuel, even a miniscule amount in the grand scheme of things, to the soulless lawnmower that has already chopped down so much of my joy in work and promises to eventually shred the paycheck, too.
('because they said so, isn't a good answer)
Regarding the legal demands here, anyone can issue anyone else a cease and desist order at any time, for anything, in the USA. The demands do not need to have merit.
"Illegal" generally refers to criminal law, not civil suits, this was essentially Anthropic threatening to file a lawsuit. Opencode was under no legal obligation to comply and was not breaking any laws, they simply decided it was easier and cheaper to comply than to fight.
What is the relevance?
If I understand correctly, OpenCode, i.e. the creator of the tool, does not use Anthropic's API. Their users do.
I am unsure where the connection can be made between the users violating some terms of service and a maker of a tool.
I think they’re okay with someone using their API with anything, including OpenCode.
Please someone correct me if I’m wrong.