--- headline: Prompt Library | Opik Documentation og:description: Learn how to push, fetch, and version prompts using Opik's Prompt Library og:site_name: Opik Documentation og:title: Getting Started with the Prompt Library — Opik title: Getting started with the Prompt Library --- Your agent depends on prompts that change frequently. The Prompt Library lets you manage them outside your codebase, version each change automatically, and link the exact version that ran to its trace. Prompt Library page showing versioned prompts ## Adding the Prompt Library to your code You can use the Opik skills to wire your existing agent up to the Prompt Library: ```bash npx skills add comet-ml/opik-skills ``` This skill is compatible with all coding agents including Claude Code, Codex, Cursor, OpenCode and more. Once the skill is installed, you can integrate with Opik using the following prompt: ``` Version my prompts in Opik using the /instrument command. ``` There are two parts: you **create** a prompt, and then you **fetch** it at runtime from inside your agent. ### Step 1 — Define and push your first prompt Push the prompt to Opik. You only do this once (or whenever you want to create a new version from code). ```python title="Python" import opik client = opik.Opik() client.create_prompt( name="system_prompt", prompt="You are a helpful assistant specializing in {{domain}}.", project_name="my-agent", ) ``` ```ts title="TypeScript" import { Opik } from "opik"; const client = new Opik(); await client.createPrompt({ name: "system_prompt", prompt: "You are a helpful assistant specializing in {{domain}}.", projectName: "my-agent", }); ``` Prompts are **project-scoped**. Always pass a `project_name` / `projectName` so two agents can use the same prompt names independently. ### Step 2 — Fetch your prompt at runtime Use `get_prompt` / `getPrompt` inside your agent to pull the version you want and render it with your runtime values. ```python title="Python" import opik client = opik.Opik() @opik.track(project_name="my-agent") def run_agent(user_input: str): prompt = client.get_prompt( name="system_prompt", project_name="my-agent", ) system_prompt = prompt.format(domain="customer support") response = call_llm( model="gpt-4o-mini", system_prompt=system_prompt, user_input=user_input, ) return response ``` ```ts title="TypeScript" import { Opik, track } from "opik"; const client = new Opik(); const runAgent = track( { name: "run_agent", projectName: "my-agent" }, async (userInput: string) => { const prompt = await client.getPrompt({ name: "system_prompt", projectName: "my-agent", }); const systemPrompt = prompt?.format({ domain: "customer support" }); const response = await callLlm({ model: "gpt-4o-mini", systemPrompt, userInput, }); return response; }, ); ``` Calling `get_prompt` / `getPrompt` inside a tracked function (`@opik.track` in Python, `track()` in TypeScript) lets Opik link the prompt version to the trace automatically. ## Choosing a version Pass the `version` parameter to control which version is returned: - **Omit `version`** (default) — The most recently created version. Useful when you want the agent to pick up new prompt edits automatically. - **`"v3"`** (or any `v` name) — A specific version. Useful when you want the prompt to stay fixed regardless of newer edits — for example, when reproducing a past run or comparing versions. ```python title="Python" # Fetch a specific version v3 = client.get_prompt(name="system_prompt", version="v3", project_name="my-agent") # Fetch the most recent version (omit `version`) latest = client.get_prompt(name="system_prompt", project_name="my-agent") ``` ```ts title="TypeScript" // Fetch a specific version const v3 = await client.getPrompt({ name: "system_prompt", version: "v3", projectName: "my-agent", }); // Fetch the most recent version (omit `version`) const latest = await client.getPrompt({ name: "system_prompt", projectName: "my-agent", }); ``` ## Chat prompts For multi-turn agents with system, user, and assistant roles, use `create_chat_prompt` / `createChatPrompt` and the matching `get_chat_prompt` / `getChatPrompt`. See [Text and chat prompts](/development/prompt-library/prompt-types) for a deeper comparison, multimodal content, and template engines. ```python title="Python" client.create_chat_prompt( name="support_assistant", messages=[ {"role": "system", "content": "You are a helpful support agent for {{company}}."}, {"role": "user", "content": "{{user_query}}"}, ], project_name="my-agent", ) chat_prompt = client.get_chat_prompt( name="support_assistant", version="v3", project_name="my-agent", ) messages = chat_prompt.format( variables={"company": "Acme", "user_query": "How do I reset my password?"}, ) ``` ```ts title="TypeScript" await client.createChatPrompt({ name: "support_assistant", messages: [ { role: "system", content: "You are a helpful support agent for {{company}}." }, { role: "user", content: "{{user_query}}" }, ], projectName: "my-agent", }); const chatPrompt = await client.getChatPrompt({ name: "support_assistant", version: "v3", projectName: "my-agent", }); const messages = chatPrompt?.format({ company: "Acme", user_query: "How do I reset my password?", }); ```