langchain-middleware SKILL.md skillA
langchain-middleware from akillness/jeo-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add akillness/jeo-skills/langchain-middleware@git:20260919.9f2a908Pins git:20260919.9f2a908 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- akillness/jeo-skills
- Path
.agent-skills/langchain-middleware/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260919.9f2a908, committed Sep 19, 2026
- Size
- 10,768 bytes
- Repository stars
- 52
- License
- none declared
INVOKE THIS SKILL when you need human-in-the-loop approval, custom middleware, or structured output. Covers HumanInTheLoopMiddleware for human approval of dangerous tool calls, creating custom middleware with hooks, Command resume patterns, and structured output with Pydantic/Zod.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
<overview>
Middleware patterns for production LangChain agents:
- **HumanInTheLoopMiddleware** / **humanInTheLoopMiddleware**: Pause before dangerous tool calls for human approval
- **Custom middleware**: Intercept tool calls for error handling, logging, retry logic
- **Command resume**: Continue execution after human decisions (approve, edit, reject)
**Requirements:** Checkpointer + thread_id config for all HITL workflows.
</overview>
---
## Human-in-the-Loop
<ex-basic-hitl-setup>
<python>
Set up an agent with HITL middleware that pauses before sending emails for approval.
```python
from langchain.agents import create_agent
from langchain.agents.middleware import HumanInTheLoopMiddleware
from langgraph.checkpoint.memory import MemorySaver
from langchain.tools import tool
@tool
def send_email(to: str, subject: str, body: str) -> str:
"""Send an email."""
return f"Email sent to {to}"
agent = create_agent(
model="gpt-4.1",
tools=[send_email],
checkpointer=MemorySaver(), # Required for HITL
middleware=[
HumanInTheLoopMiddleware(
interrupt_on={
"send_email": {"allowed_decisions": ["approve", "edit", "reject"]},
…Read the whole file at its exact version.
How to install
mdr add akillness/jeo-skills/langchain-middleware@sha256:2c5e499a818d1b17The line at the top of this page pins the label git:20260919.9f2a908, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_dq4ml6tpurucw5bm)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Sep 19, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (10768 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
akillness/jeo-skills · 52 stars · license none declared · pushed 2026-11-05 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_dq4ml6tpurucw5bm GET https://markdownregistry.com/api/v1/resolve?ref=akillness/jeo-skills/langchain-middleware GET https://markdownregistry.com/api/v1/blob/2c5e499a818d1b17bdcbe8b827c69679aab175f772e89c6180fe01fedf435968
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.