Block reference

This page describes every block offered in the editor's Library, in the order of its categories. For each block: its role, its outputs, the table of its fields and an example from customer service. Settings shared by several blocks (callable functions, phone keypad, dynamic values) are described at the end of the page.

Every block also has a Block label field at the top of the configuration panel. It is shown on the canvas and names the automatic transitions that lead to this block.

OverviewCopy Anchor Link

TriggerCopy Anchor Link

The Trigger is the starting point of the flow. It is a full AI speaking turn: it defines who the AI is, what it does when it picks up, and the functions it can call from the very first exchange. A flow created with New flow already contains one.

Output: Start, then one row per function and per automatic transition.

Example — Health insurer switchboard:

• Role prompt: "You are the front-desk assistant of Horizon Health Insurance. You address the caller formally and stay concise."
• Task prompt: "Greet the caller, mention that the call may be recorded, then ask the reason for their call."

Task prompt, system prompt or Message block? See Welcome message or prompt?.

LLM agentCopy Anchor Link

The LLM agent block is a conversational step: the AI carries on the exchange following the block's prompt, can call functions, then moves to the next block. It is the most used block in a flow.

Output: Reply, then one row per function and per automatic transition.

Example — Order tracking:

• Task prompt: "Ask the customer for the order number, then call rechercher_commande. Give the status and the expected delivery date."
• Function rechercher_commande, with a state write that keeps the status in parameters.statut_commande.

MCP toolCopy Anchor Link

The MCP tool block runs a tool as soon as the block is entered, without going through the AI, then continues to the block linked to its output. Use it for a systematic action: create a ticket in your support tool, log a callback, query your CRM.

Output: Result. It must be linked, otherwise the block shows No next step.

Once the tool is chosen, a Parameters card lists its parameters (mandatory ones are marked required). Generate args rewrites the Arguments (JSON) field with these parameters, ready to fill in.

If no MCP server is connected and the catalog is empty, the block offers manual entry of the MCP server and Tool fields. MCP servers are connected in Settings > MCP servers (see MCP servers).

Example — After a complaint, an MCP tool block systematically creates a ticket in your support tool, then continues to a confirmation Message.

HTTP requestCopy Anchor Link

The HTTP request block describes a call to an external API.

Outputs: Success (2xx) and Error / timeout.

DatastoreCopy Anchor Link

The Datastore block reads from or writes to one of your databases as soon as the block is entered, without going through the AI. The form adapts to the schema of the chosen database.

Output: Next. It must be linked, otherwise the block shows No next step.

Each value is a fixed text or a state.* path read at run time.

The How this block runs box shows the tool used for the chosen operation. If that tool does not exist yet in your workspace, a warning appears with the Create the tool now button. The Manage this database's tools (Datastores page) link opens the database. See Datastores.

Example — Identifying a customer:

1. An LLM agent asks for the customer's email and stores it in parameters.email.
2. A Datastore block: Database "Customers", Operation Search, Target field email, Searched value state.parameters.email, Result variable client.
3. The next LLM agent greets the customer with {{state.parameters.client}} in its prompt.

RoutingCopy Anchor Link

The Routing block describes a conditional branch with two cases plus a default case.

Outputs: Case A, Case B, Otherwise.

Human validationCopy Anchor Link

The Human validation block pauses the conversation until an operator decides, for example to approve a goodwill gesture. The request appears in the approvals queue; the flow resumes as soon as the decision is made, or when the timeout expires.

Outputs: Decision received and Timeout.

Each Decision field includes:

The decision is then available to the next blocks under result.<name>.

Distribute to a ViaFlow agentCopy Anchor Link

Check Distribute to a ViaFlow agent to hand the approval over to the agents of a service: an approval task is created and distributed, and the flow waits for their decision or the timeout.

A distributed task must expire: without a Max delay, 300 seconds apply. The task number is kept in state.parameters.approval_case_id; on the Timeout output, call the expireApproval tool with this number to close the task.

Example — Goodwill gesture: Title "€30 credit note", Context "Customer" → state.parameters.client, a decision field of type Text with the choices GRANT, REFUSE, Max delay 600. Decision received leads to an LLM agent that announces the decision, Timeout to a Message promising a callback.

See Human approvals.

MessageCopy Anchor Link

The Message block has the AI say a message. By default, the AI phrases it naturally in the context of the conversation; it can also recite it word for word.

Output: Next.

Example — Recording notice: "This call may be recorded to improve the quality of our services.", Recite word for word on, Wait for a reply off. See also Welcome message or prompt?.

EmailCopy Anchor Link

The Email block sends a notification email as soon as the block is entered. The recipient cannot reply to it within the conversation.

Output: Sent. It must be linked, otherwise the block shows No next step.

Example — Appointment confirmation: Recipient state.parameters.email, Subject "Your appointment is confirmed", then a Hang up block.

SMSCopy Anchor Link

The SMS block sends a notification SMS as soon as the block is entered. The recipient cannot reply to it within the conversation.

Output: Sent. It must be linked, otherwise the block shows No next step.

For the Email and SMS blocks, a warning appears in the panel if the matching sending tool is not declared in your workspace: the flow would fail on load.

Example — After an order tracking call, an SMS sends the tracking link to the caller's number, with the Reference "order-tracking".

Hang upCopy Anchor Link

The Hang up block ends the conversation. It can say a farewell message, transfer the call to an advisor and pass on end-of-call information.

Output: none.

End parametersCopy Anchor Link

• Call transfer adds in one click the Transfer number (transferNumber) and Transfer mode (transferMode) keys. On a voice call, they transfer the caller to that number.
• Transfer mode: BRIDGE (bridge: the bot stays on the line) or REFER (SIP referral: the bot leaves the call).
• Free parameter (Parameter once a row exists) adds a key of your choice; the endReason key is shown with the label End reason. A key contains only letters, digits and _; a duplicate key is flagged.
• Each value is a fixed text (abc) or a path read from the conversation (path), for example state.parameters.orderId.

In chat, end parameters are received with the end of the session. They are also recorded on the transcript and available in analytics. A value set here is never overwritten by the AI. For a complete journey, see Transfer to an advisor and Collect information.

Example — Complaint: Farewell message "I'm putting you through to an advisor, have a nice day.", Call transfer to +33123456789 in BRIDGE, and an endReason parameter = complaint.

Shared settingsCopy Anchor Link

Callable functionsCopy Anchor Link

The Trigger and LLM agent blocks offer a list of functions the AI can call. A function serves three purposes, which can be combined:

• calling a tool: when the function name matches the identifier of one of your tools, the tool is run;
• storing information through state writes;
• changing step through its output.

Click + Function to add one, then fill in:

Direct output — Draw a link from the function's output handle to the target block. Without a link, the AI stays on the block after the call.

Conditional output — Each Branch carries a condition if <value> <operator> <expected value>:

• observed value: a path, for example state.parameters.statut_commande;
• operators: = equal to, ≠ not equal to, < less than, ≤ less or equal, > greater than, ≥ greater or equal, ∈ in the list, ∉ not in list (lists in the form a, b, c);
• the first true condition wins: the order of the branches is their priority (arrows to move up or down);
• the otherwise fallback is mandatory: draw a link from its output handle.

Each branch and the fallback have their own output handle on the block.

Function detail:

Example — Function verifier_eligibilite, description "Call this function once the customer has given their contract number", write set parameters.eligible ← result.eligible, Conditional output: branch 1 state.parameters.eligible = equal to true to "Offer proposal", fallback to "Refusal explanation".

Phone keypad (DTMF)Copy Anchor Link

The Trigger, LLM agent and Message blocks let you configure phone keypad input. The keypad is always listened to; without settings, the platform defaults apply. Configure a block when it expects a specific input: menu choice, code, contract number.

Click Configure the keypad for this node, then pick a preset or adjust the fields. A box sums up live what the caller will experience.

The reset icon next to a delay restores the default value; the cross at the top of the box removes all settings.

Fixed values and pathsCopy Anchor Link

Several blocks accept, for the same value, either a fixed text or a path read at run time:

Datastore blocks only accept state.* paths. Field-by-field details are in Variables and dynamic data.

Learn moreCopy Anchor Link