
AgentGatePay
x402
Real-world tasks your agent can't do alone.

Langfuse
Hugging Face
LangSmith
OpenRouter
liteLLM
Haystack NLP Framework
Helicone AI
Framework for building applications with LLMs through composability

Which is more popular?
Based on our record, LangChain should be more popular than Underscore Done. It has been mentioned 4 times since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | underscoredone.com | langchain.com |
| Pricing | — | |
| Company | Startup from the United States · 2026 | — |
| Listed in |
In their own words, as submitted to SaaSHub.


Underscore Done (_done) is a suite of pay-per-call utility APIs built for AI agents. No API keys, no subscriptions - agents pay per request with USDC via the x402 protocol
No description of LangChain yet.
What each product offers, as listed by its team.


No features have been listed yet.
Possible disadvantages
An editorial look at what each product does well and who it suits.


No analysis of Underscore Done yet.
Overall verdict
Why this product is good
Recommended for
Walkthroughs and reviews on video.
No Underscore Done videos yet. You could help us improve this page by suggesting one.
LangChain for LLMs is... basically just an Ansible playbook
More videos
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing Underscore Done and LangChain.
Underscore Done's answer
We provide data and actions that AI cannot achieve.
Also we don't require accounts, registration, api keys. And we charge per usage and never charge monthly subscriptions.
Underscore Done's answer
Ai Agents that work on behalf of people.
Share your experience with using Underscore Done and LangChain. For example, how are they different and which one is better?
Recommendations tracked on public social media and blogs since March 2021.


_done is a catalog of small, pay-per-call utility APIs aimed at AI agents: things like DNS and WHOIS lookups, screenshots, OCR, hashing, QR codes, and SEO extraction. Every call costs one cent in USDC over x402. There's no account and no... - Source: dev.to / 13 days ago
Undoubtedly, LangChain is the most popular framework for AI application development at the moment. The advent of LangChain has greatly simplified the construction of AI applications based on Large Language Models (LLM). If we compare an... - Source: dev.to / over 2 years ago
Developed using Langchain and Streamlit technologies for enhanced performance. - Source: dev.to / over 2 years ago
LangChain was first released in October 2022 as an open-source side project, a framework that makes developing AI applications more flexible. It got so popular that it was promptly turned into a startup. - Source: dev.to / over 2 years ago
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An open protocol for internet-native payments from Coinbase
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The AI community building the future. The platform where the machine learning community collaborates on models, datasets, and applications.
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