Params

A param is a named, typed input to a whole workflow. Params turn a graph that does one thing into a graph that does a class of things.

Define them in ≔ params in the canvas topbar.

Declaring

Field	Meaning
`name`	Identifier — letters, digits, `_`, `-`
`type`	`text`, `int`, `float`, `bool`, or `json`
`default`	Pre-filled value (optional)
`description`	Shown in the run form (optional)

Using

Reference a param anywhere in prompt text or a converter template:

Review the following change and list three risks.

Area: {{param:area}}
Diff:
{{input}}

Substitution happens at run time, before the node executes. Unknown placeholders are left visible rather than silently blanked — so a typo shows up in the output instead of vanishing.

Filling

Canvas — press ▶ Run and threadle shows a form for every declared param, pre-filled with defaults and validated against each type before the run starts.

CLI — pass them as flags:

threadle run <graphId> \
  --param area="authentication" \
  --param strict=true \
  --approve-all

Values are validated the same way in both paths. A bad int stops the run before any agent is called:

param "retries" not an int: "three"

Graph settings live next door

The ≔ panel also holds two run-wide settings that are not params:

Setting	Effect
ply	Max independent nodes executing at once (default 4) — see Ply
spend tripwire (USD)	Abort the run when tracked spend reaches this ceiling — see Tripwire

Unused params are flagged

If a param is declared but never referenced, Loose ends says so:

parameter never referenced as {{param:area}}

Usually that means a renamed placeholder, not a spare param.

Patterns

One param, one spine. The bundled Starter workflow takes a single task param and threads it through plan, implement, and review stages. One input, three agents.

Params as switches. A bool param inside a converter template lets one graph produce a terse or verbose prompt without rewiring.

Params as data. A json param is validated as JSON before the run — handy for feeding a structured list into an iterator.

Running — the run form
CLI — --param flags
Lanes & value types — the same type system on wires