---
title: "Connect Langfuse and Reply - APIANT.ai"
description: "When \"New Trace\" fires in Langfuse, your agent runs \"Add contact list\" in Reply, or \"New Email Opened\" in Reply to \"Add Comment\" in Langfuse."
canonical: "https://apiant.ai/connect/langfuse-to-reply"
---

# Connect Langfuse and Reply

When **New Trace** fires in [Langfuse](https://apiant.ai/connections/langfuse), your agent runs **Add contact list** in [Reply](https://apiant.ai/connections/reply), or **New Email Opened** in Reply to **Add Comment** in Langfuse. Describe the whole flow and it is built, tested on every scenario and kept running.

Langfuse **1** trigger Langfuse **14** actions Reply **7** triggers Reply **16** actions

What the catalog holds today. Ask for anything missing and your agent reads the API documentation and adds it.

## What do you want Langfuse and Reply to do together?

Give your AI client this address.

`https://mcp.apiant.ai`

One connection does both: ask your client to act in an app once, or have it build an automation that keeps running. Any client that takes a remote MCP server. Nothing to install. Create your free account, then sign in once in your browser.

### Set it up in your client

### Claude Code

Run this in the directory you want to work in.

`claude mcp add --transport http -s project apiant-ai https://mcp.apiant.ai`

Start Claude Code there, approve the server, and sign in in the browser page it opens.

[Claude Code guide (opens in a new tab)](https://apiant.ai/docs/mcp/claude-code)

### Claude, web and desktop

Open Customize, then Connectors, then Add custom connector, and paste the address. On Team and Enterprise an owner adds it first.

[Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp)

### Cursor

Add the address to your MCP configuration as a server URL. Cursor signs you in in your browser.

[Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp)

### Zed

Open Settings, then AI, then MCP Servers, then Add Server, then Add Remote Server.

[Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp)

### Codex and the ChatGPT desktop app

Open Settings, then MCP servers, then Add server, and choose Streamable HTTP. From the terminal, Codex takes the address with its own add command and then signs you in.

[Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp)

### Any other MCP client

Paste the address where the client asks for a remote MCP server URL, and name the server apiant-ai where it lets you. APIANT's skills reach the client over the same connection.

[Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp)

Example flows

## What Langfuse and Reply can do together

### From Langfuse to Reply

- When **New Trace** in Langfuse then **Add contact list** in Reply
- When **New Trace** in Langfuse then **Add note to contact** in Reply

### From Reply to Langfuse

- When **New Email Opened** in Reply then **Add Comment** in Langfuse
- When **New Emails Sent** in Reply then **Add Dataset Item** in Langfuse

Starting points drawn from the triggers and actions in the catalog today. Describe the flow you need, at any depth, and your agent builds it and tests every scenario before it ships.

Everything your agent can do with Langfuse and Reply

## Triggers and actions 8 triggers · 30 actions

- Trigger

**New Trace**

Polling trigger: fires for newly created traces (dedup by trace id / timestamp).

- Action

**Add Comment**

Add a comment to a trace/observation/session/prompt object.

- Action

**Add Dataset**

Create a new dataset.

- Action

**Add Dataset Item**

Create an item (input/expected_output/metadata) in a dataset.

- Action

**Add Prompt**

Create a new prompt version (text or chat).

- Action

**Add Score**

Create a score attached to a trace/observation/session (numeric, categorical, or boolean).

- Action

**Delete Trace**

Delete a trace by id.

- Action

**Get Project**

Reads the Langfuse project that the connection's project-scoped API key belongs to.

- Action

**Get Prompt**

Get a prompt by name (and optional version/label).

- Action

**Get Trace**

Get a single trace by id, including nested observations/scores.

- Action

**List Dataset Items**

List items in a dataset.

- Action

**List Datasets**

List all datasets in the project.

- Action

**List Prompts**

List all prompts in the project.

- Action

**List Scores**

List scores with optional filters.

- Action

**List Traces**

List traces with optional filters (user, session, tags, timerange).

- Trigger

**Inbox Category Set for Reply**

Triggers when an email reply in Reply is given an inbox category, automatically or by a user.

- Trigger

**New Email Opened**

Triggers when a contact opens a tracked email sent from Reply.

- Trigger

**New Emails Sent**

Triggers when Reply sends an email from a sequence step.

- Trigger

**New Link Clicked**

Triggers when a recipient clicks a tracked link in an email sent from Reply.

- Trigger

**New Person Bounce**

Triggers when an email sent from Reply bounces or is rejected by the recipient's mail server.

- Trigger

**New Person Opt Out**

Triggers when a contact opts out of outreach in Reply (unsubscribe link, manual opt-out, or marked Do Not Contact).

- Trigger

**Prospect Finished**

Triggers when a contact's participation in a Reply sequence ends — completed, replied, bounced, opted out, or finished manually.

- Action

**Add contact list**

Creates a new contact list in Reply, optionally shared with your team.

- Action

**Add note to contact**

Adds a note to a contact's timeline in Reply.

- Action

**Add sequence**

Creates a new sequence in Reply with its steps, schedule, sending accounts and settings.

- Action

**Create\Update Person**

Creates a Reply contact, or updates the existing contact with the same email address.

- Action

**Delete contact**

Deletes a contact from your Reply account.

- Action

**Find contacts by criteria**

Returns the contacts that match a search term and/or field rules, optionally scoped to a contact list, sequence or sequence step.

- Action

**Get contact**

Returns one Reply contact by its id, including profile details, owner, opt-out, call and meeting status, stage and custom fields.

- Action

**Get sequence**

Returns one sequence in full: name, status, owner, schedule, settings, connected email and LinkedIn accounts, and its steps.

- Action

**List contact lists**

Returns the contact lists you own plus those shared with your team, optionally filtered by name.

- Action

**List contacts**

Returns your Reply contacts, optionally narrowed to one email address or LinkedIn profile URL.

- Action

**List inbox categories**

Returns the inbox categories you can file conversations under.

- Action

**List Sequence Contacts**

Returns the contacts enrolled in a sequence, with each contact's status, current step, added date, opt-out and call status.

- Action

**List sequences**

Returns the sequences in your Reply account, optionally filtered by status, owner, folder, archive state or name.

- Action

**Mark as Finished**

Marks one or more contacts as finished in every sequence they are in, so they receive no further sequence steps.

- Action

**Remove Person From Campaign**

Removes a contact from a sequence so they stop progressing through it. The contact and their history stay in your Reply account.

- Action

**Send Test Webhook Event**

Sends a test event from an existing Reply webhook subscription to its configured URL.

## Each app on its own

- [ **Langfuse** Langfuse is an open-source LLM engineering platform (GitHub) that helps teams collaboratively debug...](https://apiant.ai/connections/langfuse)
- [ **Reply** Reply is a sales automation platform that puts outreach on autopilot, while still making each communication...](https://apiant.ai/connections/reply)

Reviews

## What our customers say

## More from Langfuse

- [ **Langfuse to 5DollarFootball** Football fixtures, results, standings and historical odds with corner and card lines](https://apiant.ai/connect/langfuse-to-5dollarfootball)
- [ **Langfuse to Cloudflare Trace** Cloudflare Trace is a free JSON wrapper over Cloudflare's edge trace endpoint that reports what Cloudflare...](https://apiant.ai/connect/langfuse-to-cloudflare-trace)
- [ **Langfuse to PaperClean** Clean document photos for printing, remove shadows, fix lighting](https://apiant.ai/connect/langfuse-to-paperclean)
- [ **Langfuse to Postman** Postman is a platform for building and testing APIs.](https://apiant.ai/connect/langfuse-to-postman)
- [ **Langfuse to Rendobar** Hosted media processing over REST: transcode, caption, watermark video](https://apiant.ai/connect/langfuse-to-rendobar)
- [ **Langfuse to Runpod** Cloud GPU platform for renting on-demand compute to train and deploy AI models, including serverless...](https://apiant.ai/connect/langfuse-to-runpod)

## More into Reply

- [ **HubSpot to Reply** HubSpot is your all-in-one stop for all of your marketing software needs.](https://apiant.ai/connect/hubspot-to-reply)
- [ **Google Sheets to Reply** Google Sheets](https://apiant.ai/connect/google-sheets-to-reply)
- [ **Gmail to Reply** Gmail is Google’s email service, featuring spam protection, search functions, and seamless integration with...](https://apiant.ai/connect/gmail-to-reply)
- [ **Google Calendar to Reply** Google Calendar is a time management tool providing scheduling features, event reminders, and integration...](https://apiant.ai/connect/google-calendar-to-reply)
- [ **Google Drive to Reply** Google Drive is a cloud storage solution for uploading, sharing, and collaborating on files across devices...](https://apiant.ai/connect/google-drive-to-reply)
- [ **Mailchimp to Reply** Mailchimp marketing automation and email platform.](https://apiant.ai/connect/mailchimp-to-reply)

Questions

## Langfuse and Reply, answered

###

### What can start an automation from Langfuse?

Any of Langfuse's 1 trigger in the catalog, including New Trace. Describe the moment in plain language and your agent picks the right one.

###

### What can your agent do in Reply when something happens in Langfuse?

Any of Reply's 16 actions, including Create\Update Person, Send Test Webhook Event, Add contact list and Add note to contact. Your agent maps the data both ways and tests every scenario before it ships.

###

### Can it also run from Reply to Langfuse?

Yes. When something happens in Reply, your agent can act in Langfuse too. This page covers both directions: Reply's triggers and Langfuse's actions are listed here as well.

###

### Do I have to build a connector for Langfuse or Reply?

No. Both are in the catalog with their triggers and actions. You describe the automation; your agent builds it, tests every scenario and keeps it running.

###

### Can my AI client use Langfuse and Reply without building an automation?

Yes. With your AI client connected to APIANT, ask it to do something in either app once and it runs that action on the spot. Ask for an automation and your agent builds it, tests every scenario and keeps it running. One connection covers both.

###

### What happens when something fails?

Your agent works that out for you. It plans the failure paths along with the happy path, then tests every scenario before it ships.

###

### Is there a free plan?

Yes. Every plan includes the agent, including free, and building from your own AI client spends no assistant credits.
