Now open for building: Introducing Gemini CLI extensions | Hacker News Reader

Now open for building: Introducing Gemini CLI extensions

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158 pointsmeetpateltech44 comments

It looks like the key idea here is that a GitHub repo can have a gemini-extension.json file which specifies some MCP servers and a GEMINI.md file, then you can tell Gemini CLI to add that repo and it will fetch and configure those details.

Here's a commit I found adding one of these for the Google Maps platform: https://github.com/googlemaps/platform-ai/commit/95c4efdb43c...

"The extensions listed here are sourced from public repositories and created by third-party developers. Google does not vet, endorse, or guarantee the functionality or security of these extensions. Please carefully inspect any extension and its source code before installing to understand the permissions it requires and the actions it may perform. "

Extensions are always a trust challenge, but the high value of AI systems means that I expect we'll see a very high volume of attacks in the near future.

My recent experience of Gemini CLI in comparison to Claude code is very negative. For a complex task of trying to migrate some code base from CPU-only to GPU computations Claude was really helpful, and allowed me to conduct a range of experiments and converge towards sensible architecture. In the same time I simply was not able to get anything useful out of Gemini. Some code was written, but it was not tested, was failing or timing out and after repeated prodding Gemini got into loops or internal errors.

Watching Gemini CLI repo daily is great insight into how Google works. Tons of commits, three release channels, great ambitions and very little to show. These guys are running in all directions and getting nowhere.

I once spent an hour trying to get an API key for Gemini from AIStudio and Vertex, with assistance from LLMs, and finally gave up and used OpenRouter. It's that great an experience.

I just tried it today and it made a comically bad edit to my elixir file. I’ve never experienced that with Claude.

I used to use Gemini occasionally with cursor 6 months ago and it wasn’t this bad. So I’m not sure what exactly caused it to be that bad.

Gemini is really bad with tool calling, doesn't matter if you use it with Gemini CLI or with OpenCode, its just that the model itself is not a agentic model. It can be okay if only use it for asking stuff about the codebase, but not for doing agentic stuff. It'll waste large parts of its context window just failing to do tool calling properly.

The last time I was locked out of Claude Code I gave gemini cli a try. 10 minutes and lots of weird scrolling and screen flashing later, and it kept trying to add and remove the same function from the same file over and over, in a loop, until it exhausted its credits and demanded I upgrade.

working as intended.

Gemini is useless as a coding assistant.

What it excels at (because of its massive 1M token context) is code reviews. As a reference the French version of The Three Musketeers is about 700k tokens. A ~440 odd page book.

You can shove any codebase at it and ask questions about how it works and it's all in its context at the same time with no RAG magic.

Someone please explain to me the value of being able to interact with Figma via Gemini CLI?

Why would I want to do that?

Presumably the reverse would be more valuable: design something in Figma, then have Gemini CLI read from Figma and use that as a reference while writing the code.

I don't know if this is how the Figma integration works, but right now I'm just manually screenshotting my designs and passing them into Claude CLI as references for what I want, so this seems potentially more streamlined.

I don't understand why this question is being downvoted. Feels like there aren't many use cases yet

If there's value in a human using Figma, there's value in being able to give a "bot" instructions to do whatever a person might. e.g. "Gemini, update all the Figma layouts with this new text."

last I checked the Figma MCP is read-only -- "look at this figma design and implement it"

Figma MCP doesn't seem very useful at all and seem to me to compete with their newer prompt based builder. I think they're probably have their AI fork in the road. If they can't integrate these tools someone else will...

Assuming that includes reading, there’s a definite case for having your coding assistant being able to easily see the designs.

I’ve regularly used prompts along the lines ‘please modify the UI tor x feature to look like the selected Figma frame’. It’s ideal for a designing developer who wants to be much more specific about the user experience.

Cool, but at the same time, it feels overwhelming: so many different CLI or IDE tools, so many extension points. It will be fascinating to see how this all shakes out.

not in gemini-cli's flavor, it's one of the worst tools I've used

Is it model quality or the CLI itself?

I like the Gemini / Gemma family of models

It's more the agentic stuff, and things specific to the gemini-cli, which is behind the alternatives in features and capabilities. It was also making an insane number of requests (>1000 in a day, which is about the same as my Copilot usage for a month), but I'm sure they are doing their accounting differently. Google has tried to do AI accounting differently, but has acquiesced to counting tokens instead of chars, fingers crossed they do here to instead of being a snowflake that takes more effort to align in comparisons

I can't stand the cutesiness they've embedded into it either. I don't want that in a work tool

My general sense is that ai-clis will lose out to IDE integrations. I'd prefer a single tool and experience over having to context switch. Putting my AI partner in the same tool and env I use is better than having it separate with hacks to make it seem like it can be in there too, only sorta not quite

I'd add my general impression is that all the good designers that were at Google are gone, looking across their portfolio

Take even the Gemini Web App... what set Google apart in the early days? Search was just an input box, no clutter or calls to action. They have recently decided to break from this (they did have it clean beforehand) and try to get me to use image generation and other calls to action. Please get rid of the slop before I can even make my own slop!

and don't egg me on about Google Cloud... it's speed now feels like Jira, which to many people's surprise has changed course and is quite fast now

It still doesn't have an explicit planning mode, which is IMO table stakes.

I always need to remember to tell it not to touch the code, just read it or it'll take any question like "could we add library X to this" as "immediately add library X to this"...

Check this out: https://github.com/gemini-cli-extensions/security

This one seems to showcase a bunch of the "extension" features, including a custom MCP for dealing with file line numbers.

There's a fork of the repo you posted: https://github.com/QuanZhang-William/gemini-cli-security that's listed on Google's extensions gallery page: https://geminicli.com/extensions/browse/

EDIT:

I've posted about it on GitHub: https://github.com/gemini-cli-extensions/security/issues/81

Hopefully the relevant team will see it there.

Hey! I'm the PM for that extension — thanks for sharing it. Give it a try and let us know what you think about it.

Feedback, bug reports, and ideas are all welcome on the GitHub repo's issues tab. Happy to answer any questions here too.

Is it not strange that they didn't start with a Google Workspace extension? Drive, Docs, Sheets, Chat?

I think those have been around for ages already? At least via the app.

Well, this is about the CLI. I do mean the CLI.

so just a way to be able to pull in more context/info about MCP servers in the form of .MD files?

MCP servers already have the features they’re touting (preloaded prompts, custom commands etc.) so these features are redundant for most people.

But nice of them to try wrestling a file into your repo named “gemini something something”.. can’t knock them for having a go.

AFAIK this is a way to package MCP with some gemini-cli specific metadata.

aka “embrace and extend”.. minus the panache Microsoft used to do it with.

Any Claude Code users who have tried Gemini CLI? Just curious as to how it compares.

I feel no desire to switch or learn a new thing but I'm wondering if people feel like it's on par with CC or Codex or behind.

My experience was while it had longer context it didn’t do as well on coding tasks. I use CC after being on Cursor.

Same with me, I had signed up for a year plan on Cursor, used it for like... a week, then tried CC and it was so much better I signed up for the max plan and then never looked back.

Whatever Anthropic is doing, it’s working amazingly well.

And codex seems to be catching up. But gemini-cli today was really bad on an elixir edit. I’m not sure what causes it to be that bad.

Pricing

Gemini is about 10x cheaper per token. But for some reason it's using 8 times more input tokens than CC. They also have this thing called cached tokens, which is much cheaper than not cached tokens. It's a hot cache of your context on Google side, cached automatically. So at the end of the day you don't know how much you'll pay.

Models

Google is good for very complex topics and when the conversation is short. But both models are great. I prefer Claude and Sonnet 4.5 is great all around

CLI tools

Gemini cli is at it's very early days. Doesn't support hooks or subagents. Often runs into loops it can't break out from, essentially gets stuck but you still pay for the tokens.

Claude is just great. Allows you to write complex workflows they way they are supposed to be written. Handles hooks and subagents. MD file can reference another MD file, so you can DRY your files.

Nested plan mode works weird, sometimes the agent gets stuck if it asks for plan approval and thinks it's executing it, but displays nothing... So plan mode is not fully supported in subagents.

A nice thing is that .Claude directory is automatically understood by codex or cursor, you should be able to run your Claude command using openai models via codex or maybe even other providers via Cursor.

Summary

Overall Claude is the best all around, but the tokens are crazy expensive and the subscription model is a joke. You don't know how many tokens you can use when you're subscribed, but it's 'something', and last week they changed the limits, it's suddenly half of 'something'...

Using both. Sometimes Claude makes stupid mistakes, such as skipping the provided document. Overall, Claude gives better enterprise-grade suggestions and code, which Gemini sometimes misses. However, if you have in-depth documentation of the scope and implementation approach, Gemini performs better.

My primary tool is Gemini Code Assist. Claude is used to create the draft implementation approach and for a final sanity check of the code, as well as to propose enhancements for production readiness. This combination has worked well for me. Since Claude is expensive and Gemini is more affordable, it also makes economical sense.

I usually provide a well defined scope and detailed implementation approach, with the whole project split into submodules and the scope and implementation approach is again refined for each modules. In my experience, the programming language also matters, results are often better when using statically typed languages. We use C# and front end is always developed without AI.

I use Gemini Standard Tier and Claude Pro Tier.

The only compelling reason for me to try Gemini CLI opposed to Claude Code is that Gemini CLI supposedly supports ollama, which could potentially open up avenues for locally hosted agentic coding (lower quality, but private).

When I attempted to connect to my local ollama instance (~3 months ago) the Gemini CLI config and instructions just didn't work and weren't intuitive, so I gave up.

Have they figured out how to notify the user when a task is done or requires the user's input?

https://github.com/google-gemini/gemini-cli/issues/4310

Well I guess not...

Do they have a single plan yet for te CLI, assistant and image stuff?

Yeah I'm not touching MCP. Waste of time

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