Aliases

Applies to: HTTP · SDK (calling an alias) · Studio. Creating and editing aliases is an HTTP operation (or Studio); the MCP w6w_invoke tool does not take an alias — it takes a ref, see Connect an MCP client.

An alias is a name you choose, pointing at one thing you can run: an app action, a Function, a Workflow or an Endpoint. Once it exists you call the name wherever you would have passed a URN:

send-email   →   the "send" action on your SendGrid connection

Use an alias when a script, a cron job or another team hard-codes what to call, and you want to change what answers later without touching them. Re-point the alias; the callers keep using the same string.

The name

An alias name is 3–39 characters, starts with a lowercase letter, and contains only lowercase letters, digits and single hyphens: send-email, nightly-report, crm2-sync. It never contains an underscore, so it can never be mistaken for a conn_…, fn_…, wf_… or ep_… ID.

Two rules to remember:

A name is permanent. Once saved, the name of an alias cannot be changed — it is the string other people’s scripts depend on. To rename, create the new alias and delete the old one.
The target is not. You can re-point an existing alias at something else at any time.

An alias always has a target. There is no draft alias: the target must exist in your account when you save.

Create an alias

You choose the alias’s id (any non-empty string you like — it is what you use to read, update or delete it) and the name. The target says what the name runs; it takes one of four shapes:

`target.kind`	Required fields	Optional
`action`	`uses.app`, `uses.action`	`uses.connection` (a `conn_…` ID)
`function`	`function` (a `fn_…` ID)
`workflow`	`workflow` (a `wf_…` ID)
`endpoint`	`endpoint` (an `ep_…` ID)

curl -sS "$W6W_BASE_URL/aliases" \
  -H "Authorization: Bearer $W6W_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "id": "als_send_email",
    "name": "send-email",
    "displayName": "Send the welcome email",
    "description": "Calls the welcome-email Function.",
    "target": { "kind": "function", "function": "fn_01H…" }
  }'

The answer is 201 — on a create and on an update alike:

{ "alias": { "id": "als_send_email", "name": "send-email" } }

Saving again with the same id and name but a different target re-points the alias.

To list, read or delete (DELETE answers { "ok": true }):

curl -sS "$W6W_BASE_URL/aliases"            -H "Authorization: Bearer $W6W_TOKEN"
curl -sS "$W6W_BASE_URL/aliases/als_send_email" -H "Authorization: Bearer $W6W_TOKEN"
curl -sS -X DELETE "$W6W_BASE_URL/aliases/als_send_email" -H "Authorization: Bearer $W6W_TOKEN"

The list returns { "aliases": [ { id, name, displayName, description, updatedAt, target } ] } — the aliases of your current account.

Call an alias

Pass the name in the urn slot of POST /run, exactly as you would a URN. An alias carries its own target, so do not send action — it is already part of the alias.

import { W6WClient } from "@w6w/sdk";

const client = new W6WClient(); // reads W6W_BASE_URL and W6W_TOKEN

const result = await client.run({
  urn: "send-email",
  payload: { to: "ada@example.com" },
});

curl -sS "$W6W_BASE_URL/run" \
  -H "Authorization: Bearer $W6W_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{ "urn": "send-email", "payload": { "to": "ada@example.com" } }'

# or, the same alias as a URL — the request body is the payload:
curl -sS "$W6W_BASE_URL/invoke/send-email" \
  -H "Authorization: Bearer $W6W_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{ "to": "ada@example.com" }'

The answer has the same shape as calling the target directly: its kind is whatever the alias points at (action, function, or workflow with a runId — see Call any API), and it carries an invocationId you can look up under Invocations.

Errors you will see

Errors come back as { "error": { "code": "…", "message": "…" } }.

Saving an alias (POST /aliases):

Status	`code`	What it means
`400`	`invalid_body`	The body is not JSON.
`400`	`invalid_alias`	A required field is missing (`id`, `name` or `target`), `target.kind` is not one of the four, the name breaks the format above, or the target does not resolve in your account.
`409`	`alias_name_immutable`	You saved an existing alias with a different `name`. Create a new alias and delete the old one.
`409`	`alias_name_conflict`	That name is already held by another alias.
`409`	`alias_conflict`	That `id` belongs to an alias you do not own.
`404`	`unknown_alias`	`GET` or `DELETE` with an `id` that is not one of your aliases.

The “target does not resolve” message is deliberately identical whether the thing you named does not exist at all or belongs to someone else, so a save cannot be used to probe other accounts.

Calling an alias (POST /run):

Status	`code`	What it means
`400`	`invalid_body`	You sent `action` alongside an alias, or the `urn` is not a URN, key or alias at all. (`POST /invoke/<name>` answers the same condition with `invalid_urn`.)
`404`	`unknown_function`, `unknown_workflow`, `unknown_endpoint`, `unknown_connection`	The alias exists but its target has since been deleted.

Deleting a Function, Workflow, Endpoint or connection does not delete or disable an alias that points at it. The alias stays, and calls through it fail with the 404 above until you re-point or delete it. Saving an alias proves the target resolved at that moment, not for ever.

Call any API — the URN forms an alias can stand in for.
Invocations — find a call you made through an alias.

Aliases

The name

Create an alias

Call an alias

Errors you will see

Next