pi-goimports

A pi extension that runs goimports automatically after every write/edit to a *.go file, writes the formatted result back, and appends a standard unified diff to the tool result so the next turn sees the actual import/format changes. It also appends a standing rule to the system prompt once per agent run telling the model to write the code body first and let goimports manage resolvable imports.

What it does

• before_agent_start — appends a constant rule to the system prompt once per agent run (cache-safe): write the body first, let goimports add the imports it can resolve, only add non-resolvable imports manually after goimports has run. Also tells the model how to recover from a stale module cache index (run gomodindex), and notes that edits via the bash tool are not processed automatically.
• tool_result for write/edit on *.go — runs goimports (no -w/-d), which prints the formatted result to stdout without touching the file; writes it back itself and appends a standard unified diff to the tool result for the model. No-op when goimports changes nothing. When it does make changes, a compact marker (◆ goimports <path> +N -M) is appended to the chat transcript right after the tool call, so the cue persists in scrollback. Expand (ctrl+o) to see the full diff.

Binary lookup (cached per session)

goimports is resolved once at session start — on PATH, or via go env GOBIN/GOPATH if installed off-PATH. If it can't be found (or go is missing), a warning is shown at startup with install steps; install it and /reload to activate. The result is stable for the session so the system-prompt rule doesn't flip mid-run.

Install

pi install npm:pi-goimports
# or pin a version
pi install npm:[email protected]

# alternative — from git
pi install git:github.com/huww98/pi-goimports
pi install git:github.com/huww98/[email protected]

To try without installing: pi -e npm:pi-goimports.

Configuration

• PI_GOIMPORTS_ARGS — extra args appended to the goimports invocation (e.g. -local github.com/myorg for local import grouping).

Requirements

• goimports on PATH or in $GOBIN/GOPATH/bin (install with go install golang.org/x/tools/cmd/goimports@latest).
• go on PATH (goimports shells out to go for env context).
• Optional: gomodindex — rebuilds the module-cache index goimports uses to resolve imports. Run it after go get if a newly-added import isn't being resolved (goimports never refreshes the index itself, see golang/go#80087). Without it goimports still works, by scanning GOMODCACHE directly (slower). go install golang.org/x/tools/internal/modindex/gomodindex@latest.

Development

npm install
npm test  # (integration tests; requires goimports + go)
npm run typecheck

License

MIT