Segments and layout

Settings live in ~/.config/opencode-cockpit/config.json for every project, <project>/.cockpit.json for one, and on the plugin entry itself, which beats both.

{
  "statusline": {
    "surface": "bottom",
    "separator": " │ ",
    "segments": [
      "git.diff",
      { "type": "context", "style": "gradient", "width": 16 },
      { "type": "cost", "color": "#e8b923" },
      "diagnostics"
    ]
  }
}

A segment is a built-in’s name, or that name with settings. An unknown name is skipped rather than fatal: a config written against a newer version costs you a segment, not the line.

Built-in segments

Name	Shows	Settings
cwd	folder, relative to the worktree	maxWidth
git.branch	current branch, dimmed on the default branch
session.diff	+150 / -30 — what this session changed, not the working tree
model	claude-opus-5	full
context	how full the window is	style, width, warnAt, dangerAt
tokens	78.5k tok
cost	session spend	currency, showZero
todo	3/7 todo	showComplete
session.status	working, or a retry and its countdown
session.time	elapsed	coarse
diagnostics	unhealthy LSP and MCP servers
version	the bay’s version
text	literal text	value
command	a shell command’s output	name, row

Every one also takes prefix, suffix, priority, color and icon.

What session.diff counts

What this session changed — the same files OpenCode lists in its own sidebar, tracked through the session’s snapshots. Not git status: a file you edited by hand was never part of the session and will not appear, however dirty the tree is.

Both questions are worth asking, and they are different questions — “what have I changed here” is not “what has the agent changed this turn”. The working tree needs a command, because a built-in that shelled out would stop being a pure function of the snapshot, which is what makes every one of them testable without a filesystem:

{
  "statusline": {
    "modules": ["<examples/bottom.ts>"],
    "commands": { "tree": { "run": "git diff --shortstat", "intervalMs": 5000 } },
    "segments": [
      { "type": "session.diff", "prefix": "session " },
      { "type": "worktree", "prefix": "tree " }
    ]
  }
}

git diff --shortstat prints 3 files changed, 12 insertions(+), 4 deletions(-), far too long for a line — the worktree segment in examples/bottom.ts reads that and draws 3f +12 -4.

session.diff also answers to git.diff, its old and more misleading name.

Replacing OpenCode’s own sidebar blocks

The sidebar you see is not one panel — each block is an internal plugin, and tui.json can switch any of them off:

~/.config/opencode/tui.json

{
  "plugin": ["opencode-cockpit"],
  "plugin_enabled": { "internal:sidebar-context": false }
}

That removes OpenCode’s own Context / tokens / % used / spent block, leaving the space to a sidebar line of your own. It is the honest way to avoid the same figure twice: rather than this bay staying quiet about what the host says, you turn off the half you would rather not read.

Plugin	What it draws
internal:sidebar-context	tokens, context percentage, spend
internal:sidebar-files	files this session changed
internal:sidebar-todo	the todo list
internal:sidebar-lsp	language-server status
internal:sidebar-mcp	MCP server status
internal:sidebar-footer	the path and version at the bottom
internal:home-footer, internal:home-tips	the home screen’s furniture
internal:notifications	toasts

api.plugins.list() prints the current set, so the list above can be checked rather than trusted.

The context segment

Four styles, because a context meter is the segment people care most about.

style	Draws
percent	39% ctx
bar	a plain bar with end caps
gradient	a bar whose every cell is coloured by the level it stands for, green through amber to red
split	one bar coloured by what fills it — cache, fresh input, output

split is the one worth knowing about: a session that is mostly re-reading its own cache looks different from one that is mostly new input, and that difference is invisible in a percentage.

{ "type": "context", "style": "split", "width": 12, "warnAt": 0.7, "dangerAt": 0.9 }

Both hide themselves where no context window was declared. A percentage needs a denominator.

Several lines

{
  "statusline": {
    "lines": [
      { "surface": "bottom", "segments": ["git.diff", "todo", "session.time"] },
      { "surface": "sidebar", "segments": ["context", "cost"] }
    ]
  }
}

Two lines on the same surface stack, which is how a two-row statusline is written.

Each line takes its own settings:

Setting	Default
separator	" · " across, nothing down
stack	vertical in the sidebar, horizontal elsewhere
maxRows	8, vertical only
icons	on
paddingLeft / Right / Top / Bottom	per surface, to line up with OpenCode’s own content

Colour

color takes a tone name or a literal. A tone follows whatever theme you run; a literal does not.

Tones: text, muted, accent, success, warning, error, info, and background, panel, border for drawing against the window’s own surfaces.

Prefer a tone. A statusline in someone else’s palette is the first thing that makes a plugin look bolted on.

Icons

On by default, in single-width glyphs — an emoji is two cells wide in most terminals and one in a few, which is exactly what shears a fixed-width line. Turn them off with "icons": false, globally or per line, or set your own per segment with "icon": "»".