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 skills add krzysztofsurdy/code-virtuoso --skill langchain-componentsgit clone --depth 1 https://github.com/krzysztofsurdy/code-virtuosoWrote 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/skills/krzysztofsurdy/code-virtuoso/langchain-components)<a href="https://agentmods.dev/skills/krzysztofsurdy/code-virtuoso/langchain-components"><img src="https://agentmods.dev/badge/skills/krzysztofsurdy/code-virtuoso/langchain-components/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/skills/krzysztofsurdy/code-virtuoso/langchain-components"><img src="https://agentmods.dev/badge/skills/krzysztofsurdy/code-virtuoso/langchain-components.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 | $0.00056 | $0.03510 |
| Opus 5.5 | $0.00022 | $0.01404 |
| Sonnet 5.5 | $0.00011 | $0.00702 |
| Haiku 4.5 | $0.00006 | $0.00351 |
Grade A, and why
langchain-components 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 4d 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 — 215 lines — stays where its author put it; the contents beside it link to each section on GitHub.
LangChain components
The LangChain stack changes every week: model IDs, streaming and interrupt interfaces, and Deep Agents backends all moved within months. This skill therefore holds no API listings. It holds the decisions the docs do not make for you, and it points to the live docs for syntax. Fetch the current API before writing code that calls it.
Core principles
| Principle | Meaning |
|---|---|
| Fetch, do not recall | Treat any remembered signature, model ID, or import path as stale until the docs confirm it |
| Match the installed version | Read versions from the lockfile first, then fetch docs for that line |
| Smallest layer that fits | Start at the highest-level tool that covers the need and drop down only when it cannot |
| One agent first | Add multi-agent structure only after a single agent with good tools and prompt fails |
| State must be persisted to pause | Interrupts, resume, and multi-turn memory all depend on a checkpointer |
| Model output is untrusted input | Tool arguments and retrieved text can be wrong or hostile |
Version matrix
Checked on 2026-10-21 against PyPI and the official release policy.
| Package | Current | Python | Stability |
|---|---|---|---|
langchain |
1.4.6 | 3.10+ | v1 semver: breaking changes only in 2.0 |
langgraph |
1.2.16 | 3.10+ | v1 semver: breaking changes only in 2.0 |
deepagents |
0.7.29 | 3.11+ | 0.x: no stability promise, pin it and read changelogs |
The v1 promise, from the official release policy: minor releases add features without breaking changes, deprecated features keep working through the whole 1.x series, and 1.0 is a long-term-support release that stays active until 2.0. Legacy LangChain 0.3 and LangGraph 0.4 are in maintenance until December 2026. Code written for those lines (AgentExecutor, create_react_agent, legacy chains) needs migration, not patching.
Read installed versions before anything else:
grep -A1 -E '^name = "(langchain|langgraph|deepagents|langchain-core)"' uv.lock poetry.lock 2>/dev/null
pip show langchain langgraph deepagents 2>/dev/null | grep -E '^(Name|Version)'
What ships with it
17 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.
- references/agents.md 13 KB
- references/deep-agents.md 14 KB
- references/integrations.md 10 KB
- references/langgraph-advanced.md 14 KB
- references/langgraph-core.md 16 KB
- references/langgraph-state.md 14 KB
- references/memory.md 9.3 KB
- references/messages.md 9.5 KB
- references/middleware.md 13 KB
- references/models.md 11 KB
- references/multi-agent.md 11 KB
- references/providers.md 7.7 KB
- references/retrieval.md 10 KB
- references/runtime.md 6.3 KB
- references/streaming.md 12 KB
- references/testing.md 8.1 KB
- references/tools.md 10 KB
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.
- 4d ago Changed · +65 lines · -53 tokens per session 1d9a702211a0
- 1mo ago First seen · 150 lines · 109 tokens per session scan A ff2834d24f03
langchain-components is a skill published in the GitHub repository krzysztofsurdy/code-virtuoso (36 stars, last pushed 2d ago), licensed MIT. It adds 56 tokens to every session and 3,510 once invoked, about $0.0002 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 2026-08-30.
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