Glossary of Slen terms

The words the console and this reference use — operation, flow, version, execution, reservation, pool, customer, credits — and what each one means.

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The console, the API and this reference call the same things by the same names. This page says what each name means. The terms stand in groups, in the order a request meets them.

Requests

Term	What it is
Operation	One model call of a flow, with everything that happened to it — the attempts, the reservation, the cost. The list is on Operations.
Operation code	The name you give a kind of request, such as `generate_email`. A request that runs a flow names its code, and the code decides which flow runs.
Operation binding	The link between an operation code and a flow, set in the settings of the flow. One code belongs to one flow of a project, and a flow has one code. See AI flows.
Execution	One run of a flow. A finished execution is `completed`, `rejected`, `failed` or `uncertain`. One that is not finished is `queued`, `running` or `waiting`.
Trace	The record of an execution, node by node and event by event.

Flows

Term	What it is
Flow, AI flow	A graph that decides what a request may spend. See How a flow is built.
Flow builder	The editor of a flow — the palette of nodes, the canvas and the inspector of a node.
Canvas	The surface of the builder where the nodes of a flow stand.
Node	One step of a flow.
Port	A named exit of a node. See Ports and branching.
Connection	A line from a port of one node to another node. A provider connection is another thing — see below.
Branch	The path that starts at a port.
Entry node	The node a flow starts at, Request. A flow has one.
Terminal node	A node that ends a path, Return Response or Reject Request.
Template	A ready flow to start from. The gallery is on Templates.

Versions

Term	What it is
Version	A numbered state of a flow. A version is either a draft or published, and a published version never changes. See Publish, versions and rollback.
Draft	The version that is being edited. A flow has at most one draft, and requests never run it.
Publish	Check the draft and, when it has no errors, make it a published version. The flow runs that version from then on.
Active version	The published version requests run. It is the last published one until a rollback, and the one rolled back to after it. The draft of a flow starts from the active version. The Versions tab of a flow gives it the status Active.
Roll back	Make another published version the active one. Executions that are already running are not affected.

Money

Term	What it is
Estimate	What a call is expected to cost, worked out before the call is made. An estimate spends nothing.
Reservation, hold	Money set aside for a call before the call is made. Only a reservation in the `authorized` status keeps money aside. How budget reservations work tells the statuses apart.
Authorization	A reservation as the API and the console record it — its amount, its status and what was captured. The tab is on Operations — see Operations, authorizations and the ledger.
Capture	Close a reservation by what the call actually cost. The rest of the reservation is given back.
Release	Give a reservation back in full. Nothing is charged.
Ledger	The list of the money movements of a project. Entries are only added to it, never changed.
Budget	A spending ceiling of a project or of the organization. It is set in money or, for one kind of budget, in the number of reservations held at the same time.
Policy	A rule that is applied to a request before money is reserved. It refuses the request or changes its limits.

Providers and models

Term	What it is
Provider	The company whose models are called.
Provider connection	The credentials of one provider account that Slen calls models through.
Provider pool	A group of provider connections with the strategy by which one of them is chosen for a call.
Model	A model of the catalogue with its token prices. The catalogue is on Models.
Cache hit, cache miss	A hit means the cache has an answer for the request, so the flow can answer without calling a model. A miss means it has none.

Customers

Term	What it is
Customer	An end customer of yours. Slen knows a customer by the id your application gives them, `external_user_id`, which a request that runs a flow sends in `context.user_id`.
Credits	The unit you count your customers' usage in. Credits are not money. A model call holds credits before it runs, spends them on capture and gets them back on release.
Credit account	The credits of one customer in one credit type: the balance, what is held, and the settings — whether it may go below zero and when it warns. A customer has an account for each credit type.
Charge	Credits your application takes from a customer by itself, for something it sells outside a flow. A charge is not spend of a call.
Block	A stop on the runs of one customer: their new runs are refused, and their credits can still be moved. See Customer credits.

Access

Term	What it is
Organization	Your company in Slen. It holds the projects, the members and the settings they share.
Project	A part of an organization with its own API keys, flows and operations.
Member	A person of the organization, with a role.
API key	The secret a service sends with every request. A key belongs to one project. See Manage API keys.
Scope, permission	What a key may do. See Authentication.
Approval	A decision an execution waits for. A person approves or rejects it on Approvals.
Alert	A notice that a condition you set a rule for has come true.
Notification	A message Slen sends to a person or to a chat of the team about an alert or an approval. See Notifications.
Webhook	A request Slen sends to your service when an event happens.
Audit log	The history of actions and changes in the organization.