> For the complete documentation index, see [llms.txt](https://docs.middle.app/middle-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.middle.app/middle-docs/product/accounts/workflow-parameters.md). # Workflow parameters Parameters select data and calculate values for workflow steps and triggers. You can use them to build an Action's inputs, make a Decision, set a variable, or decide whether a trigger should discard or requeue a record. The pages below follow the groups in the parameter dropdown. Each option includes its JSON type, how its inputs work, and a complete example. ## Variables Variables allow you to select data within your workflow, including Begin step inputs, module variables, and values saved by earlier steps. You can also [define your own workflow variables](/middle-docs/product/accounts/defining-workflow-variables.md). See [Variables](/middle-docs/product/accounts/workflow-parameters/variables.md) for Variable Selector, Parameter-scoped variable, and the keys used in copied workflows. ### Now vs. Start time **Now** is the time when the parameter is evaluated. **Start time** is when the workflow was queued or when the trigger activity occurred. If a workflow is re-executed or a trigger is requeued, its Start time does not change. In JSON, `NOW_REAL` means Now and `NOW` means Start time. See [Now vs. Start time](/middle-docs/product/accounts/workflow-parameters/variables.md#now-vs-start-time) for examples. ## Constant and Calculated Values Use a fixed value or calculate one from other parameters. See [Constants and Calculated Values](/middle-docs/product/accounts/workflow-parameters/constants-and-calculated-values.md) for Number, Parse Number, Text, Boolean, and Null. ## Flow Control Flow controls allow you to build out decision logic within Decision steps and Action steps. See [Flow Control](/middle-docs/product/accounts/workflow-parameters/flow-control.md) for If, And, Or, Switch, and every comparison option. ## Dates and Datetimes Create, format, and work with dates and times. See [Dates and Datetimes](/middle-docs/product/accounts/workflow-parameters/dates-and-datetimes.md) for Date, Time, Datetime, Construct Time, Construct Datetime, Timedelta, formatting, parsing, and timezone conversion. ## Text Manipulation Text manipulation parameters can be added before a text variable or text constant. See [Text Manipulation](/middle-docs/product/accounts/workflow-parameters/text-manipulation.md) for stripping characters, splitting lines, and changing capitalization. ## Array Manipulation An array is a list of values, such as the line items in an invoice. See [Array Manipulation](/middle-docs/product/accounts/workflow-parameters/array-manipulation.md) for Map, Reduce, Filter, Sort, First Match, Count, and De-duplicate. ## Advanced Parameters Build an object or a list of values, often for an Action's inputs. See [Advanced Parameters](/middle-docs/product/accounts/workflow-parameters/advanced-parameters.md) for Construct Object and Construct Array. ## Special Controls to delete, move, and duplicate parameters. These change the parameter tree in the editor; they are not values that run in a workflow. See [Special](/middle-docs/product/accounts/workflow-parameters/special.md) for each command and examples of the resulting JSON. ## Reading the JSON For the surrounding workflow structure, step connections, and canvas positions, see [Workflow JSON](/middle-docs/product/accounts/create-or-copy-a-workflow/workflow-json.md). This section describes the parameters inside steps. When you copy a workflow, each parameter is a tree: a parent parameter can contain other parameters in its `params` array. Their order matters. The examples in this reference use this copied-workflow format, not the editor's internal API format. | Key | Meaning | | ------------- | --------------------------------------------------------------------------- | | `type` | The raw parameter type, such as `template` for Text or `comparison` for If. | | `expression` | Value or setting: text, formula, variable key, or comparison operator. | | `params` | Child parameters in order. Each child is another complete parameter object. | | `key` | The field name when a parameter supplies a field in a Construct Object. | | `props` | Field path to select from the result, such as `["customer", "email"]`. | | `output_name` | Array operation's parameter-scoped variable name, such as `"items"`. | An `output_name` of `"items"` provides `items:value` and `items:index`. Keys that are not needed can be omitted. A parameter's result has a type: text, number, boolean, date, time, datetime, null, object, array, or a reference to a synced record. The surrounding field determines which types are allowed. Null is a missing value; it is not the text `"null"`. For example, this complete Text parameter returns `Hello Sally`. The first child supplies the first `{}` placeholder. ```json { "type": "template", "expression": "Hello {}", "params": [ {"type": "template", "expression": "Sally"} ] } ``` The examples are parameter objects, rather than whole workflows, unless a page says otherwise. Variable examples state which inputs or saved values they require. To understand a copied workflow, follow its step connections, check the declared input and variable types, and then read each parameter tree using the pages above. --- # Agent Instructions This documentation is published with GitBook. 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