MCP support

[jfilby]

Please add support for MCP. This would make it easy to extend the functionality of the code harness in a standard way.

[capocasa]

I wouldn't rule it out- the reason it's not there right now is that MCP uses A LOT LIKE A HORRIBLE LOT of context. Things like MCP are kind of the reason 3code exists- anthropic optimizes for MAXIMUM POWER WITH TOMORROWS ECONOMICS. 3code doesn't do that. So I would need some kind of genius idea to implement MCP in a creatievly token saving way to include it, which I haven't found so far.

There is another standardized alternative- skills that use command line tools. Those work already. Direct 3code to follow instructions in a myskill.md file. Any file in ~/.agents/skills or ~/.3code/skills will be mentioned in the system prompt, so you if you name it instructively, it will load. 3code does that internally too- so if you ask for research, the web search skill will load, but if you don't, you don't waste the tokens.

[juancarlospaco]

Any way to connect with LM Studio or similar local-LLM?

[capocasa]

You can use it with ollama for sure, but you'd need at least an RTX 3090 or similar and Qwen 3.5 to get somewhat ok results. I was only able to get really good programming results with cloud models that need like 10x48G VRAM.

[jfilby]

But this is just a request for support to allow people to do this, it doesn't mean they have to use MCP. It can be useful for connecting external APIs.

[juancarlospaco]

LM Studio uses local HTTP API.

[capocasa]

But this is just a request for support to allow people to do this, it doesn't mean they have to use MCP. It can be useful for connecting external APIs.

Fair enough- I have things like 'web search' as an internal skills/web-search.md file so the same could be done with MCP. But the darned protocol is shockingly huge though.

Edit: You see, in most agents, everything is part of the system prompt, even if folks don't use it- for 3code, we don't want that, e.g. the claude code system prompt is like 50k tokens. That's fine if you're sitting on an endless supply of tokens like anthropic engineers are but it's sure not fine if you're paying for them.

[jfilby]

It could be useful to wrap an existing Python MCP client, if you do decide to add the functionality.

[capocasa]

Oh now way I'm big on keeping it at tiny binary- but thanks for the suggestion!

But what you got totally right is that there's no need to reinvent MCP- I would likely find out which library is the best match for 3code and then have 3code translate it into Nim.

But the problem was always how to have it available in a way that doesn't clash with the 3code philosophy- I think Anthropic is notorious for its living in a kind of detached elite world of free tokens and I think MCP is kind of designed like that, so how exactly to tune and implement it is going to take some brain power to get right. First things first- I'm fixing bugs. Well, telling 3code/glm-5.2 to.

[jfilby]

I took your advice and found another way besides MCP, so you can close this issue if you like.

[capocasa]

Nice!!! Which way, if you don't mind me asking?