feat: install tab completion for bash, zsh, and fish (#16)

`completions install` generates the script from the same clap definition
the binary parses with, so it cannot drift from `--help`, and writes it
where each shell already looks. fish scans its own completions directory
unprompted; bash and zsh get one marked `source` line appended to their rc
file, because nothing puts a per-user directory on their search path by
default. `completions uninstall` takes back exactly those lines and leaves
the rest of the file alone.

Cargo.lock

@@ -497,6 +497,15 @@ dependencies = [
  "terminal_size",
 ]
 
+[[package]]
+name = "clap_complete"
+version = "4.6.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "db8b397918185f0161ff3d6fcaa9e4bfc09b8367caf6e1d4a2848e5477ed027b"
+dependencies = [
+ "clap",
+]
+
 [[package]]
 name = "clap_derive"
 version = "4.6.1"
@@ -2478,6 +2487,7 @@ version = "8.0.0"
 dependencies = [
  "chrono",
  "clap",
+ "clap_complete",
  "color-eyre",
  "directories",
  "dotenv",

README.md

@@ -149,17 +149,18 @@ soulseek-rs shares list|add|remove|status|reindex
 soulseek-rs config path|list|get|set
 soulseek-rs portmap                       # test automatic port mapping
 soulseek-rs skills install|uninstall|list # teach a coding agent this CLI
+soulseek-rs completions install|uninstall # tab completion for bash/zsh/fish
 ```
 
 `whoami`, `config` and `shares list|add|remove` are the ones a script runs
 first: the config commands need no account at all, and `whoami` answers
 "are these credentials good and what am I offering" in one call.
 
-Eleven of these need no credentials, because they never touch the network:
-`config path|list|get|set`, `shares list|add|remove`, `portmap` and
-`skills install|uninstall|list`. `shares status` and `shares reindex` are not
-among them: they report what the network will see, which means logging in and
-scanning the folders.
+Thirteen of these need no credentials, because they never touch the network:
+`config path|list|get|set`, `shares list|add|remove`, `portmap`,
+`skills install|uninstall|list` and `completions install|uninstall`.
+`shares status` and `shares reindex` are not among them: they report what the
+network will see, which means logging in and scanning the folders.
 
 Every command emits records except the four that perform an action.
 `room say`, `message send`, `shares add` and `shares remove` say nothing on
@@ -278,6 +279,30 @@ soulseek-rs skills install --dir ~/.config/some-agent/skills
 soulseek-rs skills install --dir .claude/skills   # commit it with the repo
 ```
 
+### Shell completions
+
+Tab completion is generated from the same `clap` definition the binary parses
+with, so it never drifts from `--help`:
+
+```bash
+soulseek-rs completions install
+```
+
+That covers whichever of bash, zsh and fish this machine uses, writing each
+script where that shell already looks — `~/.config/fish/completions` is scanned
+unprompted, while bash and zsh also get one marked `source` line appended to
+`~/.bashrc` or `~/.zshrc`, because nothing else puts a per-user directory on
+their search path. Open a new shell and `soulseek-rs sh<TAB>` completes.
+
+```
+installed   zsh    /home/you/.local/share/zsh/site-functions/_soulseek-rs
+installed   fish   /home/you/.config/fish/completions/soulseek-rs.fish
+```
+
+`completions uninstall` removes the scripts and takes back exactly the lines it
+added, leaving the rest of your rc file alone. Pass `--shell bash` (repeatable)
+to act on one shell rather than the ones detected.
+
 ### Sharing
 
 `serve` is the mode that makes this client a source: it stays logged in, keeps

soulseek-rs/Cargo.toml

@@ -28,6 +28,7 @@ workspace = true
 soulseek-rs-lib = { version = "8.0.0", path = "../soulseek-rs-lib" }
 
 clap = { version = "4.6.2", features = ["derive", "color", "wrap_help", "env"] }
+clap_complete = "4.6.7"
 ratatui = "0.30.2"
 color-eyre = "0.6.5"
 dotenv = "0.15.0"

soulseek-rs/README.md

@@ -37,6 +37,7 @@ soulseek-rs message send|read
 soulseek-rs shares list|add|remove|status|reindex
 soulseek-rs config path|list|get|set
 soulseek-rs portmap                       # test automatic port mapping
+soulseek-rs completions install           # tab completion for bash/zsh/fish
 ```
 
 Add `--json` for newline-delimited JSON instead of tab-separated text, so

soulseek-rs/src/SKILL.md

@@ -97,6 +97,10 @@ answered, which is a negative answer rather than an error.
 this skill file into the local agent directories, or remove it: `agent`,
 `path`, `action`.
 
+**`completions install`** and **`completions uninstall`** — write the tab
+completion script where bash, zsh, or fish looks for it, or take it back
+again: `shell`, `path`, `action`. For a human at a prompt, not for you.
+
 ## Idioms
 
 ```bash

soulseek-rs/src/cli.rs

@@ -27,6 +27,7 @@ Examples:
   soulseek-rs serve --follow --json             share files, stream upload events
   soulseek-rs user someuser                     is this peer online and worth it
   soulseek-rs skills install                    teach your coding agent this CLI
+  soulseek-rs completions install               tab completion for your shell
 
 Exit codes:
   0 success   2 usage/config   3 connect or login   4 no results
@@ -198,6 +199,35 @@ pub enum Commands {
     /// Teach a local coding agent this command surface
     #[command(subcommand)]
     Skills(SkillsCommand),
+
+    /// Tab completion for bash, zsh, and fish
+    #[command(subcommand)]
+    Completions(CompletionsCommand),
+}
+
+#[derive(Subcommand, Debug)]
+pub enum CompletionsCommand {
+    /// Write the completion script where the shell looks for it
+    Install(CompletionsArgs),
+
+    /// Remove the completion script again
+    Uninstall(CompletionsArgs),
+}
+
+#[derive(Args, Debug)]
+pub struct CompletionsArgs {
+    /// Shell to act on instead of the ones found on this machine; repeat for
+    /// several
+    #[arg(long, value_enum, action = ArgAction::Append)]
+    pub shell: Vec<Shell>,
+}
+
+/// The shells with a conventional per-user completions location.
+#[derive(Copy, Clone, Debug, PartialEq, Eq, ValueEnum)]
+pub enum Shell {
+    Bash,
+    Zsh,
+    Fish,
 }
 
 #[derive(Subcommand, Debug)]

soulseek-rs/src/commands/completions.rs

@@ -0,0 +1,405 @@
+//! Tab completion for the shell: `completions`.
+//!
+//! The script is generated from the same `clap` definition the binary parses
+//! with, so it never drifts. Installing means putting it where the shell
+//! already looks — which is enough on its own only for fish; bash and zsh each
+//! get one `source` line appended to their rc file, marked so `uninstall` can
+//! take back exactly what was added and nothing else.
+
+use crate::cli::{Cli, CompletionsArgs, CompletionsCommand, Shell};
+use crate::output::{CliError, CliResult, CompletionRecord, Out};
+use clap::CommandFactory;
+use directories::UserDirs;
+use std::io::Write;
+use std::path::{Path, PathBuf};
+
+/// The command being completed, and the file name the scripts are written as.
+const BIN: &str = "soulseek-rs";
+
+/// What every line this command writes into an rc file ends with, and the only
+/// thing `uninstall` will delete from one.
+const MARKER: &str = "# soulseek-rs completions";
+
+/// The directories the install locations hang off, resolved once so the rest
+/// of the module is a pure function of them.
+struct Dirs {
+    home: PathBuf,
+    data: PathBuf,
+    config: PathBuf,
+}
+
+/// One shell's completion script, and the rc file that has to load it.
+struct Target {
+    shell: Shell,
+    script: PathBuf,
+    /// `None` for fish, whose completions directory is scanned automatically.
+    rc: Option<PathBuf>,
+}
+
+impl Target {
+    fn record(&self, action: &str) -> CompletionRecord {
+        CompletionRecord {
+            shell: self.shell.name().to_string(),
+            path: self.script.display().to_string(),
+            action: action.to_string(),
+        }
+    }
+
+    fn source_line(&self) -> String {
+        format!("source \"{}\" {MARKER}", self.script.display())
+    }
+}
+
+impl Shell {
+    const fn name(self) -> &'static str {
+        match self {
+            Self::Bash => "bash",
+            Self::Zsh => "zsh",
+            Self::Fish => "fish",
+        }
+    }
+
+    const fn generator(self) -> clap_complete::Shell {
+        match self {
+            Self::Bash => clap_complete::Shell::Bash,
+            Self::Zsh => clap_complete::Shell::Zsh,
+            Self::Fish => clap_complete::Shell::Fish,
+        }
+    }
+}
+
+pub fn run(out: &Out, command: &CompletionsCommand) -> CliResult {
+    match command {
+        CompletionsCommand::Install(args) => install(out, &targets(args)?),
+        CompletionsCommand::Uninstall(args) => uninstall(out, &targets(args)?),
+    }
+}
+
+fn install(out: &Out, targets: &[Target]) -> CliResult {
+    for target in targets {
+        let mut changed = write_script(&target.script, &script(target.shell))?;
+        if let Some(rc) = &target.rc {
+            changed |= add_source_line(rc, &target.source_line())?;
+        }
+        out.emit(&target.record(if changed {
+            "installed"
+        } else {
+            "unchanged"
+        }));
+    }
+    out.status("open a new shell to pick it up");
+    Ok(())
+}
+
+fn uninstall(out: &Out, targets: &[Target]) -> CliResult {
+    for target in targets {
+        let mut changed = remove_script(&target.script)?;
+        if let Some(rc) = &target.rc {
+            changed |= remove_source_lines(rc)?;
+        }
+        out.emit(&target.record(if changed { "removed" } else { "absent" }));
+    }
+    Ok(())
+}
+
+/// The completion script as this binary's own argument parser defines it.
+fn script(shell: Shell) -> Vec<u8> {
+    let mut buffer = Vec::new();
+    clap_complete::generate(
+        shell.generator(),
+        &mut Cli::command(),
+        BIN,
+        &mut buffer,
+    );
+    buffer
+}
+
+/// Which shells to act on. Naming shells aims the command at exactly those;
+/// detection is what answers the question when nothing does.
+fn targets(args: &CompletionsArgs) -> CliResult<Vec<Target>> {
+    let dirs = Dirs::detect()?;
+    let shells = if args.shell.is_empty() {
+        let found = detected(&dirs, std::env::var("SHELL").ok().as_deref());
+        if found.is_empty() {
+            return Err(CliError::no_results(
+                "no bash, zsh, or fish setup found in your home directory; \
+                 name one with --shell",
+            ));
+        }
+        found
+    } else {
+        args.shell.clone()
+    };
+    Ok(shells
+        .into_iter()
+        .map(|shell| target(shell, &dirs))
+        .collect())
+}
+
+/// Where each shell looks. bash and zsh both read a per-user directory that
+/// nothing puts on the search path by default, hence the rc line; fish scans
+/// its own completions directory unprompted.
+fn target(shell: Shell, dirs: &Dirs) -> Target {
+    let (script, rc) = match shell {
+        Shell::Bash => (
+            dirs.data.join("bash-completion/completions").join(BIN),
+            Some(bash_rc(&dirs.home)),
+        ),
+        Shell::Zsh => (
+            dirs.data.join("zsh/site-functions").join(format!("_{BIN}")),
+            Some(dirs.home.join(".zshrc")),
+        ),
+        Shell::Fish => (
+            dirs.config
+                .join("fish/completions")
+                .join(format!("{BIN}.fish")),
+            None,
+        ),
+    };
+    Target { shell, script, rc }
+}
+
+/// A shell counts as present when it has left configuration behind, or when it
+/// is the one the user is logged into — a fresh macOS zsh account has no
+/// `.zshrc` at all until something writes one.
+fn detected(dirs: &Dirs, login_shell: Option<&str>) -> Vec<Shell> {
+    let running =
+        |name: &str| login_shell.is_some_and(|path| path.ends_with(name));
+    [
+        (
+            Shell::Bash,
+            dirs.home.join(".bashrc").exists()
+                || dirs.home.join(".bash_profile").exists()
+                || running("bash"),
+        ),
+        (
+            Shell::Zsh,
+            dirs.home.join(".zshrc").exists() || running("zsh"),
+        ),
+        (
+            Shell::Fish,
+            dirs.config.join("fish").is_dir() || running("fish"),
+        ),
+    ]
+    .into_iter()
+    .filter_map(|(shell, present)| present.then_some(shell))
+    .collect()
+}
+
+/// Interactive bash reads `.bashrc`, except on machines where only the login
+/// file exists — which is the common macOS shape.
+fn bash_rc(home: &Path) -> PathBuf {
+    let profile = home.join(".bash_profile");
+    let rc = home.join(".bashrc");
+    if !rc.exists() && profile.exists() {
+        profile
+    } else {
+        rc
+    }
+}
+
+impl Dirs {
+    fn detect() -> CliResult<Self> {
+        let home = UserDirs::new()
+            .map(|dirs| dirs.home_dir().to_path_buf())
+            .ok_or_else(|| {
+                CliError::usage("cannot find your home directory")
+            })?;
+        Ok(Self {
+            data: xdg("XDG_DATA_HOME", &home, ".local/share"),
+            config: xdg("XDG_CONFIG_HOME", &home, ".config"),
+            home,
+        })
+    }
+}
+
+/// Shells follow the XDG layout on every platform, unlike this client's own
+/// config, which follows each platform's convention (see `persist::paths`).
+fn xdg(variable: &str, home: &Path, fallback: &str) -> PathBuf {
+    std::env::var_os(variable)
+        .filter(|dir| !dir.is_empty())
+        .map_or_else(|| home.join(fallback), PathBuf::from)
+}
+
+fn write_script(path: &Path, script: &[u8]) -> CliResult<bool> {
+    if std::fs::read(path).is_ok_and(|found| found == script) {
+        return Ok(false);
+    }
+    create_parent(path)?;
+    std::fs::write(path, script).map_err(|e| unwritable(path, &e))?;
+    Ok(true)
+}
+
+fn remove_script(path: &Path) -> CliResult<bool> {
+    match std::fs::remove_file(path) {
+        Ok(()) => Ok(true),
+        Err(e) if e.kind() == std::io::ErrorKind::NotFound => Ok(false),
+        Err(e) => Err(unwritable(path, &e)),
+    }
+}
+
+fn add_source_line(rc: &Path, line: &str) -> CliResult<bool> {
+    let existing = std::fs::read_to_string(rc).unwrap_or_default();
+    if existing.lines().any(|found| found == line) {
+        return Ok(false);
+    }
+    create_parent(rc)?;
+    let separator = if existing.is_empty() || existing.ends_with('\n') {
+        ""
+    } else {
+        "\n"
+    };
+    let mut file = std::fs::OpenOptions::new()
+        .create(true)
+        .append(true)
+        .open(rc)
+        .map_err(|e| unwritable(rc, &e))?;
+    writeln!(file, "{separator}{line}").map_err(|e| unwritable(rc, &e))?;
+    Ok(true)
+}
+
+/// Take back only the marked lines. Somebody else's rc file is a bad thing to
+/// rewrite from memory, so every other line is preserved verbatim.
+fn remove_source_lines(rc: &Path) -> CliResult<bool> {
+    let Ok(existing) = std::fs::read_to_string(rc) else {
+        return Ok(false);
+    };
+    let kept: Vec<&str> = existing
+        .lines()
+        .filter(|line| !line.ends_with(MARKER))
+        .collect();
+    if kept.len() == existing.lines().count() {
+        return Ok(false);
+    }
+    let mut rewritten = kept.join("\n");
+    if !rewritten.is_empty() {
+        rewritten.push('\n');
+    }
+    std::fs::write(rc, rewritten).map_err(|e| unwritable(rc, &e))?;
+    Ok(true)
+}
+
+fn create_parent(path: &Path) -> CliResult {
+    match path.parent() {
+        Some(parent) => {
+            std::fs::create_dir_all(parent).map_err(|e| unwritable(parent, &e))
+        }
+        None => Ok(()),
+    }
+}
+
+fn unwritable(path: &Path, error: &std::io::Error) -> CliError {
+    CliError::usage(format!("cannot write {}: {error}", path.display()))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn dirs(home: &Path) -> Dirs {
+        Dirs {
+            home: home.to_path_buf(),
+            data: home.join(".local/share"),
+            config: home.join(".config"),
+        }
+    }
+
+    /// The rc line only works because sourcing the script registers the
+    /// completion rather than just defining a function. zsh is the one that
+    /// could plausibly go the other way: an autoload-style `#compdef` file does
+    /// nothing on its own, so the install rests on the footer clap emits.
+    #[test]
+    fn a_sourced_script_registers_the_command() {
+        let zsh = String::from_utf8(script(Shell::Zsh)).expect("utf-8");
+        assert!(zsh.contains("compdef _soulseek-rs soulseek-rs"));
+        let bash = String::from_utf8(script(Shell::Bash)).expect("utf-8");
+        assert!(bash.contains("complete -F _soulseek-rs"));
+    }
+
+    #[test]
+    fn each_shell_lands_where_it_already_looks() {
+        let home = PathBuf::from("/home/me");
+        let dirs = dirs(&home);
+        for (shell, script, rc) in [
+            (
+                Shell::Bash,
+                ".local/share/bash-completion/completions/soulseek-rs",
+                Some(".bashrc"),
+            ),
+            (
+                Shell::Zsh,
+                ".local/share/zsh/site-functions/_soulseek-rs",
+                Some(".zshrc"),
+            ),
+            // fish scans its own completions directory, so it needs no rc line.
+            (
+                Shell::Fish,
+                ".config/fish/completions/soulseek-rs.fish",
+                None,
+            ),
+        ] {
+            let target = target(shell, &dirs);
+            assert_eq!(target.script, home.join(script));
+            assert_eq!(target.rc, rc.map(|file| home.join(file)));
+        }
+    }
+
+    #[test]
+    fn only_shells_this_machine_uses_become_targets() {
+        let home = tempfile::tempdir().expect("tempdir");
+        let dirs = dirs(home.path());
+        assert!(detected(&dirs, None).is_empty());
+        assert_eq!(detected(&dirs, Some("/bin/zsh")), [Shell::Zsh]);
+
+        std::fs::write(home.path().join(".bashrc"), "").expect("bashrc");
+        std::fs::create_dir_all(dirs.config.join("fish")).expect("fish");
+        assert_eq!(detected(&dirs, None), [Shell::Bash, Shell::Fish]);
+    }
+
+    #[test]
+    fn bash_falls_back_to_the_login_file_when_that_is_all_there_is() {
+        let home = tempfile::tempdir().expect("tempdir");
+        assert_eq!(bash_rc(home.path()), home.path().join(".bashrc"));
+
+        std::fs::write(home.path().join(".bash_profile"), "").expect("write");
+        assert_eq!(bash_rc(home.path()), home.path().join(".bash_profile"));
+
+        std::fs::write(home.path().join(".bashrc"), "").expect("write");
+        assert_eq!(bash_rc(home.path()), home.path().join(".bashrc"));
+    }
+
+    #[test]
+    fn installing_twice_adds_one_line_and_uninstalling_takes_only_that() {
+        let home = tempfile::tempdir().expect("tempdir");
+        let rc = home.path().join(".zshrc");
+        std::fs::write(&rc, "export EDITOR=vi").expect("rc");
+        let target = target(Shell::Zsh, &dirs(home.path()));
+        let line = target.source_line();
+
+        assert!(add_source_line(&rc, &line).expect("add"));
+        assert!(!add_source_line(&rc, &line).expect("add again"));
+        let after = std::fs::read_to_string(&rc).expect("read");
+        assert_eq!(after, format!("export EDITOR=vi\n{line}\n"));
+
+        assert!(remove_source_lines(&rc).expect("remove"));
+        assert!(!remove_source_lines(&rc).expect("remove again"));
+        assert_eq!(
+            std::fs::read_to_string(&rc).expect("read"),
+            "export EDITOR=vi\n"
+        );
+    }
+
+    #[test]
+    fn a_script_is_written_once_and_removed_once() {
+        let home = tempfile::tempdir().expect("tempdir");
+        let path = target(Shell::Fish, &dirs(home.path())).script;
+        let fish = script(Shell::Fish);
+
+        assert!(write_script(&path, &fish).expect("write"));
+        assert!(!write_script(&path, &fish).expect("write again"));
+        assert_eq!(std::fs::read(&path).expect("read"), fish);
+
+        assert!(remove_script(&path).expect("remove"));
+        assert!(!remove_script(&path).expect("remove again"));
+    }
+}

soulseek-rs/src/commands/mod.rs

@@ -5,6 +5,7 @@
 //! first; the ones that only read the config file or the local machine are
 //! dispatched by `main::run` before any credentials are demanded.
 
+pub mod completions;
 pub mod peer;
 pub mod settings;
 pub mod skills;
@@ -196,7 +197,10 @@ pub fn run(ctx: &Ctx, command: Commands) -> CliResult {
         // These need no account, so main.rs answers them before asking for
         // credentials; the arms exist only to keep the match exhaustive.
         Commands::Portmap => portmap(&ctx.out, ctx.settings.listen_port),
-        Commands::Config(_) | Commands::Shares(_) | Commands::Skills(_) => {
+        Commands::Config(_)
+        | Commands::Shares(_)
+        | Commands::Skills(_)
+        | Commands::Completions(_) => {
             Err(CliError::usage("handled without a session; see main::run"))
         }
     }

soulseek-rs/src/main.rs

@@ -64,6 +64,9 @@ fn run(mut cli: Cli, out: &Out) -> CliResult {
         Commands::Skills(ref command) => {
             return commands::skills::run(out, command);
         }
+        Commands::Completions(ref command) => {
+            return commands::completions::run(out, command);
+        }
         Commands::Config(ConfigCommand::Path) => {
             return commands::settings::config_path(out, &store);
         }

soulseek-rs/src/output.rs

@@ -445,6 +445,28 @@ impl Record for SkillRecord {
     }
 }
 
+/// What happened to one shell's completion script.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize)]
+pub struct CompletionRecord {
+    /// `bash`, `zsh`, or `fish`.
+    pub shell: String,
+    pub path: String,
+    /// `installed` (written), `unchanged` (already identical), `removed`, or
+    /// `absent`.
+    pub action: String,
+}
+
+impl Record for CompletionRecord {
+    fn text(&self) -> String {
+        format!(
+            "{}\t{}\t{}",
+            sanitize(&self.action),
+            sanitize(&self.shell),
+            sanitize(&self.path)
+        )
+    }
+}
+
 /// The result of probing automatic port mapping.
 #[derive(Debug, Clone, PartialEq, Eq, Serialize)]
 pub struct PortmapRecord {

soulseek-rs/tests/cli_e2e.rs

@@ -93,8 +93,15 @@ fn help_lists_every_scriptable_command() {
     assert_eq!(code(&output), EXIT_OK);
     let help = stdout(&output);
     for command in [
-        "search", "download", "get", "browse", "room", "message", "portmap",
+        "search",
+        "download",
+        "get",
+        "browse",
+        "room",
+        "message",
+        "portmap",
         "skills",
+        "completions",
     ] {
         assert!(help.contains(command), "--help should mention {command}");
     }
@@ -333,6 +340,51 @@ fn listing_skills_reports_without_writing_anything() {
     );
 }
 
+/// fish is the shell the whole round trip can be driven for on every platform:
+/// its completions directory hangs off `XDG_CONFIG_HOME`, so nothing outside
+/// the scratch directory is read or written. bash and zsh also append a line
+/// to a real rc file under `$HOME`, which is not a thing to point a test at on
+/// Windows — the unit tests cover that half.
+#[test]
+fn installing_completions_is_repeatable_and_reversible() {
+    let target = Scratch::new("completions");
+    let installed = target
+        .path()
+        .join("fish")
+        .join("completions")
+        .join("soulseek-rs.fish");
+    let completions = |verb: &str| {
+        command(&["--json", "completions", verb, "--shell", "fish"])
+            .env("XDG_CONFIG_HOME", target.path())
+            .output()
+            .expect("the binary should run")
+    };
+
+    let first = completions("install");
+    assert_eq!(code(&first), EXIT_OK, "stderr: {}", stderr(&first));
+    assert_eq!(action(&first), "installed");
+    let script = std::fs::read_to_string(&installed).expect("a fish script");
+    assert!(script.contains("complete -c soulseek-rs"));
+    assert!(
+        script.contains("-l download-dir"),
+        "flags are completed too"
+    );
+
+    assert_eq!(
+        action(&completions("install")),
+        "unchanged",
+        "reinstalling is how you update"
+    );
+
+    let removed = completions("uninstall");
+    assert_eq!(action(&removed), "removed");
+    assert!(!installed.exists());
+
+    let again = completions("uninstall");
+    assert_eq!(code(&again), EXIT_OK, "removing nothing is not a failure");
+    assert_eq!(action(&again), "absent");
+}
+
 // ---------------------------------------------------------------------------
 // Server required (soulfind)
 // ---------------------------------------------------------------------------

website/src/pages/docs.tsx

@@ -181,14 +181,19 @@ export const Docs = () => {
               <Code>download</Code>, <Code>browse</Code>, <Code>room</Code>,{' '}
               <Code>message</Code>, <Code>serve</Code>, <Code>user</Code>,{' '}
               <Code>whoami</Code>, <Code>shares</Code>, <Code>config</Code>,{' '}
-              <Code>portmap</Code>, <Code>skills</Code>. Records are tab-separated fields,
-              one per line, or NDJSON with <Code>--json</Code>.
+              <Code>portmap</Code>, <Code>skills</Code>, <Code>completions</Code>. Records
+              are tab-separated fields, one per line, or NDJSON with <Code>--json</Code>.
             </p>
             <p>
               No TTY, no daemon. <Code>search --json</Code> pipes through <Code>jq</Code>{' '}
               into <Code>download --stdin</Code>. Every ending has its own exit code: 4 found
               nothing, 3 could not reach the server, 6 the transfer died.
             </p>
+            <p>
+              <Code>completions install</Code> gives bash, zsh and fish tab completion for
+              all of it, generated from the same definition the binary parses with.{' '}
+              <Code>completions uninstall</Code> takes it back out.
+            </p>
             <p>
               <Code>portmap</Code> tests whether your router will let peers connect back,
               worth running once.{' '}

website/src/pages/install.tsx

@@ -301,6 +301,12 @@ export const Install = () => {
               a terminal and the TUI opens, in a script or a pipe it wants a subcommand
               instead.
             </p>
+            <p className="text-[13px] text-muted">
+              <Code>soulseek-rs completions install</Code> then adds tab completion to
+              whichever of bash, zsh and fish this machine uses &mdash; generated from the
+              same definition the binary parses with, so it never drifts from{' '}
+              <Code>--help</Code>. Open a new shell to pick it up.
+            </p>
             <div className="flex flex-wrap gap-2 sm:gap-3">
               <Button href={LINKS.releases}>Prebuilt binaries</Button>
             </div>
@@ -519,13 +525,17 @@ export const Install = () => {
 
       <Section band>
         <SectionHead eyebrow="uninstall" title="Removing it completely.">
-          Three things exist on disk: the binary, the config, and the state. Nothing else,
+          Three things exist on disk: the binary, the config, and the state &mdash; plus
+          the completion scripts and the agent skill, if you asked for those. Nothing else,
           unless you point <Code>--log-file</Code> somewhere. No telemetry to opt out of.
         </SectionHead>
         <Cols start>
           <Terminal
             label="macOS · Linux"
             lines={[
+              { t: 'cm', text: '# while the binary is still there' },
+              { t: 'cmd', text: 'soulseek-rs completions uninstall' },
+              { t: 'cmd', text: 'soulseek-rs skills uninstall' },
               { t: 'cmd', text: 'cargo uninstall soulseek-rs' },
               { t: 'cm', text: '# config and state: searches, downloads, rooms, messages' },
               {
@@ -539,6 +549,7 @@ export const Install = () => {
           <Terminal
             label="Windows · PowerShell"
             lines={[
+              { t: 'cmd', text: 'soulseek-rs skills uninstall' },
               { t: 'cmd', text: 'cargo uninstall soulseek-rs' },
               {
                 t: 'cmd',