# Qst API
This document describes the script API contract for qst.
The script catalog and community scripts are documented in:
- https://github.com/gitanelyon/awesome-qst
# Script API
This is the contract for scripts placed in `~/.config/qst/scripts/`. qst is the host runtime; scripts are standalone programs that communicate with it through a line-oriented protocol on standard output.
Supported script styles:
- Executable scripts or binaries, run directly.
- Non-executable scripts with supported extensions, dispatched through an interpreter:
- `.sh`, `.bash`, `.zsh`, `.fish`
- `.py`
- `.pl`
- `.rb`
- `.js`
- `.lua`
## Invocation model
- Scripts are invoked with the current query payload as command-line arguments.
- qst parses standard output line by line.
- Empty lines are ignored.
## Item output
- `Title|Value` produces a list row with visible title `Title` and payload `Value`.
- `Title` is shorthand for a row where the payload defaults to the title.
## Host directives
Lines prefixed with `qst! ` are control directives:
- `qst! title <text>`
- Sets the list title.
- `qst! message <text>`
- Sets the status or message line under the input.
- `qst! clear_message`
- Clears the status or message line.
- `qst! action <Action>`
- Sets the default action for all list rows.
- `qst! item_action <Action>`
- Sets the action for only the next emitted row.
- `qst! default_item_action <Action>`
- Sets the action for all following rows unless overridden.
- `qst! item <title>|<value>|<Action>`
- Emits an explicit row with an optional per-item action.
- `qst! clear`
- Clears all accumulated rows.
- `qst! single <query>|<result>`
- Returns a single-result response instead of list mode.
- `qst! write <file>|<WriteAction>|<value>`
- Mutates `~/.config/qst/storage/<script-name>/<file>`.
- `qst! read <file>`
- Reads the entire file and emits each stored line as a row.
- `qst! read <file>|<ReadAction>`
- Reads the file with the specified action and emits the result as a single row.
- `qst! delete <file>`
- Deletes the stored file.
- `qst! log <message>`
- Writes a timestamped message to `~/.local/state/qst/<script-name>.log`.
## Script metadata
Scripts can declare a metadata header near the top of the file:
```bash
echo "qst! meta My Awesome script, 1.0.0, John Doe, This script does awesome things!"
```
The fields are, in order:
- `name`
- `version`
- `author`
- `description`
The header is parsed by qst as a first-class directive. After the header has been emitted, scripts can request one field at a time:
- `qst! meta name`
- `qst! meta version`
- `qst! meta author`
- `qst! meta description`
Helper scripts such as `help.sh` and `loader.sh` can read the same header to surface script details in their own UI, and they can also use the selector form when they need a single metadata field in a response.
Use the selector form when only one metadata field is needed.
## Row metadata
Row metadata is appended to a directive or row using `@meta:<key>=<value>` tokens.
Example:
```bash
Rules:
- Metadata tokens are appended at the end of the row or directive payload.
- Multiple metadata tokens may be chained in the same row.
- If a literal `/@meta` is used at the start of a row, qst treats it as normal text.
Supported row metadata keys:
- `display=<text>`
- Overrides the visible label for the row.
- `fuzzy=<bool>`
- Opts the row into host-side fuzzy filtering. When attached to a title or message directive, it enables fuzzy filtering for the entire script response.
- `meta=<terms>`
- Adds hidden search terms. Separate multiple terms with commas.
- `nonselectable=<bool>`
- Skips the row during selection movement.
- `permanent=<bool>`
- Keeps the row available for UI flows that preserve permanent rows.
- `active=<bool>`
- Renders the row with the active-state styling.
- `center=<bool>`
- Centers the row within the available text area.
- `urgent=<bool>`
- Moves the row to the top of the list and renders it in bold red without an inline prefix.
## Supported actions
Actions are evaluated left to right and can be combined with commas, for example `CopyToClipboard,ExitApp` or `Execute,RefreshResults`.
### Main Actions
- `CopyToClipboard`
- Copies the value to the clipboard and keeps qst open.
- `SetStatusMessage`
- Sets the status or message line to the row value.
- `ClearStatusMessage`
- Clears the status or message line.
- `SetSearchQuery`
- Replaces the current query with the row value.
- `AppendToQuery`
- Appends the row value to the current query.
- `PrependToQuery`
- Inserts the row value at the beginning of the current query.
- `ReplaceLastToken`
- Replaces the trailing whitespace-delimited token with the row value.
- `PopLastToken`
- Removes the trailing whitespace-delimited token from the current query.
- `PopLastChar`
- Removes the last character from the current query.
- `ClearQuery`
- Clears the entire query.
- `RefreshResults`
- Re-runs filtering and script resolution without changing the query text.
- `Execute`
- Executes the row value as a shell command and keeps qst open.
- `ExitApp`
- Exits qst.
- `ResetPrompt`
- Resets the search query back to its first token. For example, `todo n example` becomes `todo `. If it follows `Execute` in the same action list, qst waits for that command to finish first.
- `None`
- No-op action; keeps qst open.
### Write Actions
- `pfront`
- Pushes the value to the front of the file.
- `pback`
- Pushes the value to the back of the file.
- `rmfront`
- Removes a line from the front of the file.
- `rmback`
- Removes a line from the back of the file.
- `purge`
- Removes every stored line that exactly matches the provided value.
### Read Actions
- `fpeek`
- Reads a line from the front of the file without removing it.
- `bpeek`
- Reads a line from the back of the file without removing it.
- `all`
- Reads the entire file content.
Storage files are created automatically when a write directive targets a missing file.
## Minimal example
```bash
#!/usr/bin/env bash
query="${1:-}"
echo "qst! title Demo Script "
if [[ -z "$query" ]]; then
echo "qst! action None"
echo " Type a command after the trigger|"
else
echo "qst! action Execute,ExitApp"
echo " Run: $query|$query"
fi
```
For real-world patterns and authoring guidance, see the `awesome-qst` repository:
- https://github.com/gitanelyon/awesome-qst