Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/ashish7802/awesome-api-skills/langchainnpx skills add ashish7802/awesome-api-skills --skill langchaingit clone --depth 1 https://github.com/ashish7802/awesome-api-skillsWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.00711 |
| Opus 5 | $0.00000 | $0.00356 |
| Sonnet 5 | $0.00000 | $0.00142 |
| Haiku 4.5 | $0.00000 | $0.00071 |
Grade A, and why
langchain scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 72 lines — stays where its author put it; the contents beside it link to each section on GitHub.
LangChain Skill
Framework for developing applications powered by language models.
Ecosystem Graph Preview
graph LR
langchain["langchain"]:::core
classDef core fill:#f9f,stroke:#333,stroke-width:4px;
langchain -- "alternative to" --> llamaindex
langchain -- "integrates with" --> openai
langchain -- "integrates with" --> pinecone
llamaindex -- "alternative to" --> langchain
ollama -- "integrates with" --> langchain
vllm -- "integrates with" --> langchain
Recommended Next Skills
- llamaindex (Score: 0.93) Why: Direct relationship, Both are AI, Shared ecosystem (ai), Can deploy to any, Similar network profile
- ollama (Score: 0.83) Why: Direct relationship, Both are AI, Shared ecosystem (ai), Similar network profile
- vllm (Score: 0.82) Why: Direct relationship, Both are AI, Shared ecosystem (ai), Similar network profile
Quick Start
LangChain provides standard interfaces for LLMs, Vector Stores, and Memory, allowing you to chain them together to build complex Agents and Retrieval-Augmented Generation (RAG) pipelines.
pip install langchain langchain-openai
Production Patterns
LCEL (LangChain Expression Language)
Avoid using massive legacy chain classes (like ConversationalRetrievalChain). Migrate entirely to LCEL, which uses Python pipe operators (|) to compose prompts, models, and output parsers declaratively. It automatically handles streaming and async logic.
Architecture & Scaling
Agents vs Chains
A Chain is a deterministic sequence of operations. An Agent utilizes an LLM's reasoning to dynamically determine which Tools to execute and in what order to solve a complex goal.
Error Recovery
LLMs frequently output invalid JSON when asked for structured data. Use LangChain's OutputFixingParser which automatically catches parsing errors and feeds the broken output back to the LLM with instructions to fix it.
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- yesterday First seen · 72 lines · 0 tokens per session scan A 921c327ba7c1
langchain is a skill published in the GitHub repository ashish7802/awesome-api-skills (13 stars, last pushed 13d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 711 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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