> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/warpdotdev/warp/llms.txt
> Use this file to discover all available pages before exploring further.
# Shell completions and autosuggestions in Warp
> Warp's warp_completer engine provides tab completions, argument descriptions, and autosuggestions that work across bash, zsh, fish, and PowerShell sessions.
Warp ships its own completion engine — the `warp_completer` crate — that runs entirely within the Warp process and provides rich, context-aware suggestions as you type. Unlike traditional shell completions that rely solely on the shell's built-in `complete` or `compgen` mechanisms, Warp's engine parses the command line token by token, resolves argument types, and surfaces completions with inline descriptions so you can understand each option before accepting it.
## How the completion engine works
When you start typing in Warp's input area, the `warp_completer` engine:
1. **Tokenizes** the buffer text into a sequence of `LiteCommand` and `ParsedTokenData` objects, tracking each token's position (span), its index within the command, and its type.
2. **Describes** each token using the `describe` function, which matches the token against a completion spec to determine what kind of value is expected (a subcommand, a flag, a file path, a custom enum, etc.).
3. **Generates suggestions** by calling the `suggestions` function with the current `CompletionContext`. Suggestions are ranked by a `Priority` score and may be matched using exact, prefix, or fuzzy strategies.
4. **Displays results** inline as you type (autosuggestions) and in a pop-up list when you press `Tab`.
The snapshot of parsed tokens (`ParsedTokensSnapshot`) is cached between keystrokes so that re-parsing only happens when the buffer actually changes.
## Completion specs
Warp uses **completion specs** — structured definitions that describe a command's subcommands, flags, and arguments. These specs power the detailed inline descriptions you see next to each suggestion (for example, `--verbose: Enable verbose output`).
Warp's completion specs are partly derived from the community-maintained [Fig completion specs](https://github.com/withfig/autocomplete) library (acknowledged as an open-source dependency) and partly from Warp's own spec format. The `v2` completions feature flag enables the next-generation spec engine that supports JavaScript-executed generators for dynamic completions.
The `v2` completion engine (feature flag `v2`) supports `JsExecutionContext` and `JsExecutionError`, which allow spec authors to write JavaScript generator functions that produce completions dynamically at runtime — for example, by reading the output of a command or querying an API.
## Tab completions
Press `Tab` in the input area to request completions for the current token. Warp opens a completion pop-up that shows:
* **Matching suggestions** ranked by relevance.
* **Type labels** — whether the suggestion is a subcommand, flag, file path, or other type.
* **Inline descriptions** from the completion spec (where available).
Use the arrow keys or `Tab`/`Shift+Tab` to move through suggestions, and press `Enter` or `Space` to accept the highlighted item.
For commands that Warp does not have a spec for, completions fall back to the shell's native completion system. Warp calls into the shell's completer via the `NativeShellCompletions` feature path, so your custom bash/zsh/fish completions still work inside Warp.
## Autosuggestions
As you type, Warp shows a **ghost text** autosuggestion to the right of your cursor. The suggestion is drawn from:
* Your **command history** — the most recent matching command is shown first.
* **Completion specs** — if the spec defines a default or most-likely next token, Warp may suggest it inline.
Press the right arrow key (`→`) or `End` to accept the full autosuggestion. Press `Ctrl+→` (or `Option+→` on macOS) to accept one word at a time.
## How Warp completions differ from traditional shells
| Feature | Traditional shell | Warp |
| ------------------------- | ------------------------------------------ | ---------------------------------------- |
| Completion UI | Plain list in the terminal stream | Pop-up with type labels and descriptions |
| Argument descriptions | Not shown | Shown inline from completion specs |
| History-based suggestions | Partial (fish, zsh-autosuggestions plugin) | Built in, no plugin required |
| Dynamic generators | Shell functions only | JavaScript generators (v2) |
| Cross-session history | Shell-dependent | Stored in Warp's SQLite history database |
| Spec source | Shell built-ins + manual setup | Fig-compatible specs + Warp's own specs |
## Completion matching strategies
Warp supports multiple match strategies, selectable per completion context:
The suggestion starts with the characters you have typed. This is the most predictable mode and is used for flag names and subcommands where exact spelling matters.
Characters you type are matched anywhere in the suggestion, in order but not necessarily consecutively. Fuzzy matching is useful for long flag names or file paths where you know a distinctive substring.
The suggestion must match your input exactly (case-sensitive or case-insensitive depending on the `TopLevelCommandCaseSensitivity` setting). Used for commands where partial matches would be ambiguous.
## File and path completions
When the current token is expected to be a file path, Warp's `engine` module walks the file system using `EngineDirEntry` and `EngineFileType` to list files and directories. The path separator is resolved via `PathSeparators::for_os()`, so completions work correctly on both POSIX systems (forward slash) and Windows (backslash).
## Alias completions
If you have defined shell aliases, Warp resolves them during completion. The `suggest::alias` module expands aliases so that completions for the underlying command are available even when you type the alias name.
## Configuring completions
There are no required configuration changes to enable completions — they work out of the box. To fine-tune behavior, open **Settings → Features** in Warp.
```toml theme={null}
# Example: disable autosuggestions (not yet a public setting, shown for illustration)
# Completions are configured through the Warp Settings UI.
```
Some shell initialization scripts (for example, `compinit` calls in `.zshrc`) may print output during shell startup that briefly appears in the terminal. This is normal and does not affect Warp's completions.