Borrowing it
Nothing to install: this file belongs to TheSethRose/Copilot-Skills. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/TheSethRose/Copilot-Skills/main/.github/instructions/langchain.instructions.mdgit clone --depth 1 https://github.com/TheSethRose/Copilot-SkillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/thesethrose/copilot-skills/langchain)<a href="https://agentmods.dev/instructions/thesethrose/copilot-skills/langchain"><img src="https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/langchain/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/thesethrose/copilot-skills/langchain"><img src="https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/langchain.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What 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 5.1 | $0.01269 | $0.01269 |
| Opus 5.5 | $0.00508 | $0.00508 |
| Sonnet 5.5 | $0.00254 | $0.00254 |
| Haiku 4.5 | $0.00127 | $0.00127 |
Grade A, and why
Copilot-Skills langchain.instructions.md 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 1mo ago.
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 — 206 lines — stays where its author put it; the contents beside it link to each section on GitHub.
LangChain Instructions
Auto-loaded when: Working with files matching: **/*.py, **/*.ipynb, **/langchain*
Default Behaviors
When working with LangChain:
- Use LLM Abstractions: Always use LangChain's LLM interfaces for flexibility
- Chain Composition: Build complex workflows using chains
- Memory Management: Use memory classes for conversation context
- Output Parsing: Parse LLM outputs consistently
- Error Handling: Handle API rate limits and connection errors
- Logging: Enable LangChain debug logging when troubleshooting
Common Workflows
Basic Chain Setup
from langchain_core.prompts import ChatPromptTemplate
from langchain_openai import ChatOpenAI
llm = ChatOpenAI(model="gpt-4o", temperature=0.7)
prompt = ChatPromptTemplate.from_messages([
("system", "You are a helpful assistant."),
("user", "{input}")
])
chain = prompt | llm
result = chain.invoke({"input": "What is LangChain?"})
With Claude
from langchain_anthropic import ChatAnthropic
llm = ChatAnthropic(model="claude-3-sonnet-20250219")
chain = prompt | llm
response = chain.invoke({"input": "Explain quantum computing"})
RAG (Retrieval Augmented Generation)
from langchain.vectorstores import Chroma
from langchain_openai import OpenAIEmbeddings
from langchain_core.runnables import RunnablePassthrough
# Setup retriever
embeddings = OpenAIEmbeddings()
vectorstore = Chroma.from_documents(documents, embeddings)
retriever = vectorstore.as_retriever()
# RAG chain
rag_chain = (
{"context": retriever, "question": RunnablePassthrough()}
| prompt
| llm
)
result = rag_chain.invoke("What is in the documents?")
With Memory (Conversation)
from langchain.memory import ConversationBufferMemory
from langchain.chains import ConversationChain
memory = ConversationBufferMemory()
conversation = ConversationChain(
llm=llm,
memory=memory,
verbose=True
)
response = conversation.predict(input="Hello!")
response = conversation.predict(input="What did I just say?")
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.
- 1mo ago First seen · 206 lines · 1,269 tokens per session scan A d3377f6508ed
Copilot-Skills langchain.instructions.md is an instructions file published in the GitHub repository TheSethRose/Copilot-Skills (3 stars, last pushed 10mo ago), licensed MIT. It adds 1,269 tokens to every session, about $0.0051 per session on Opus 5.5. 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 2026-08-31.
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