--- title: "Connect Langfuse and PostHog - APIANT.ai" description: "When \"New Trace\" fires in Langfuse, your agent runs \"Capture Event\" in PostHog, or \"Action Performed\" in PostHog to \"Add Comment\" in Langfuse." canonical: "https://apiant.ai/connect/langfuse-to-posthog" --- # Connect Langfuse and PostHog When **New Trace** fires in [Langfuse](https://apiant.ai/connections/langfuse), your agent runs **Capture Event** in [PostHog](https://apiant.ai/connections/posthog), or **Action Performed** in PostHog 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 PostHog **1** trigger PostHog **9** 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 PostHog 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 PostHog can do together ### From Langfuse to PostHog - When **New Trace** in Langfuse then **Capture Event** in PostHog - When **New Trace** in Langfuse then **Add annotation** in PostHog ### From PostHog to Langfuse - When **Action Performed** in PostHog then **Add Comment** in Langfuse - When **Action Performed** in PostHog 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 PostHog ## Triggers and actions 2 triggers ยท 23 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 **Action Performed** Triggers when an action is performed by a user. - Action **Add annotation** Create a new annotation on the project timeline (content, date_marker, scope). - Action **Capture Event** Captures an event. - Action **Evaluate feature flags** Evaluate all feature flag values for a given distinct_id/person, returning flag states for use in automation branching. - Action **Get person** Retrieve a single person by ID. - Action **List annotations** List annotations in the project. - Action **List cohorts** List cohorts defined in the project. - Action **List feature flags** List feature flags defined in the project. - Action **List insights** List saved insights (charts/graphs) in the project. - Action **List persons** List/search persons in the project, optionally filtered by distinct_id or properties. ## 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) - [ **PostHog** PostHog is the single platform for building successful products.](https://apiant.ai/connections/posthog) 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 PostHog - [ **Google Sheets to PostHog** Google Sheets is Google's online spreadsheet app for creating, editing and sharing spreadsheets.](https://apiant.ai/connect/google-sheets-to-posthog) - [ **HubSpot to PostHog** HubSpot is your all-in-one stop for all of your marketing software needs.](https://apiant.ai/connect/hubspot-to-posthog) - [ **Salesforce to PostHog** Salesforce is a leading enterprise customer relationship management (CRM) platform.](https://apiant.ai/connect/salesforce-to-posthog) - [ **Google Calendar to PostHog** Google Calendar is a time management tool providing scheduling features, event reminders, and integration...](https://apiant.ai/connect/google-calendar-to-posthog) - [ **Google Drive to PostHog** Google Drive is a cloud storage solution for uploading, sharing, and collaborating on files across devices...](https://apiant.ai/connect/google-drive-to-posthog) - [ **Mailchimp to PostHog** Mailchimp marketing automation and email platform.](https://apiant.ai/connect/mailchimp-to-posthog) Questions ## Langfuse and PostHog, 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 PostHog when something happens in Langfuse? Any of PostHog's 9 actions, including Add annotation, Capture Event, Evaluate feature flags and Get person. Your agent maps the data both ways and tests every scenario before it ships. ### ### Can it also run from PostHog to Langfuse? Yes. When something happens in PostHog, your agent can act in Langfuse too. This page covers both directions: PostHog's triggers and Langfuse's actions are listed here as well. ### ### Do I have to build a connector for Langfuse or PostHog? 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 PostHog 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.