Syntax reference

Every construct the editor understands, with a live example. Paste any snippet into the editor to try it.

Title

Set a diagram title.

title: My Diagram
A -> B: hello

A synchronous call with a solid arrow.

A -> B: request

A response or async return with a dashed arrow.

A --> B: response

An open arrowhead for async messages.

A ->> B: async event

A message that never arrives.

A -x B: dropped

Arrowheads on both ends.

A <-> B: sync

An emphasized message.

A => B: important

A participant messaging itself.

A -> A: internal work

Give a participant a short id used elsewhere.

Payment Service as pay
Client -> pay: charge

Attach a note to one or more participants.

A -> B: hi
note A: a single-participant note

A conditional branch.

if: authorized
  A -> B: proceed
else: denied
  A -> B: stop
end

Group related messages.

group: retry
  A -> B: attempt
end

Visual separators: thin, regular, dashed, bold.

A -> B: one
--: phase two
A -> B: two

Indicate elapsed time.

A -> B: start
...: some time later
B --> A: done

Force participant order.

order: B, A
A -> B: hi

Number every message automatically.

// autonumber
A -> B: first
B -> A: second

Inline *italic*, **bold**, ~~strike~~, and `code`.

A -> B: **bold** and *italic* and `code`

Font Awesome {fa…} tokens are recognized and ignored in v1.

A -> B: {fa-user} sign in

Lines starting with // are ignored.

// this is a comment
A -> B: hi