| name | browse |
| version | 1.1.0 |
| description | Fast headless browser for QA testing and site dogfooding. Navigate any URL, interact with
elements, verify page state, diff before/after actions, take annotated screenshots, check
responsive layouts, test forms and uploads, handle dialogs, and assert element states.
~100ms per command. Use when you need to test a feature, verify a deployment, dogfood a
user flow, or file a bug with evidence. Use when asked to "open in browser", "test the
site", "take a screenshot", or "dogfood this".
|
| allowed-tools | ["Bash","Read","AskUserQuestion"] |
Preamble (run first)
_UPD=$(~/.claude/skills/gstack/bin/gstack-update-check 2>/dev/null || .claude/skills/gstack/bin/gstack-update-check 2>/dev/null || true)
[ -n "$_UPD" ] && echo "$_UPD" || true
mkdir -p ~/.gstack/sessions
touch ~/.gstack/sessions/"$PPID"
_SESSIONS=$(find ~/.gstack/sessions -mmin -120 -type f 2>/dev/null | wc -l | tr -d ' ')
find ~/.gstack/sessions -mmin +120 -type f -delete 2>/dev/null || true
_CONTRIB=$(~/.claude/skills/gstack/bin/gstack-config get gstack_contributor 2>/dev/null || true)
_PROACTIVE=$(~/.claude/skills/gstack/bin/gstack-config get proactive 2>/dev/null || echo "true")
_BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
echo "BRANCH: $_BRANCH"
echo "PROACTIVE: $_PROACTIVE"
source <(~/.claude/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || true
REPO_MODE=${REPO_MODE:-unknown}
echo "REPO_MODE: $REPO_MODE"
_LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
echo "LAKE_INTRO: $_LAKE_SEEN"
_TEL=$(~/.claude/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
_TEL_PROMPTED=$([ -f ~/.gstack/.telemetry-prompted ] && echo "yes" || echo "no")
_TEL_START=$(date +%s)
_SESSION_ID="$$-$(date +%s)"
echo "TELEMETRY: ${_TEL:-off}"
echo "TEL_PROMPTED: $_TEL_PROMPTED"
mkdir -p ~/.gstack/analytics
echo '{"skill":"browse","ts":"'$(date -u +%Y-%m-%dT%H:%M:%SZ)'","repo":"'$(basename "$(git rev-parse --show-toplevel 2>/dev/null)" 2>/dev/null || echo "unknown")'"}' >> ~/.gstack/analytics/skill-usage.jsonl 2>/dev/null || true
for _PF in ~/.gstack/analytics/.pending-*; do [ -f "$_PF" ] && ~/.claude/skills/gstack/bin/gstack-telemetry-log --event-type skill_run --skill _pending_finalize --outcome unknown --session-id "$_SESSION_ID" 2>/dev/null || true; break; done
If PROACTIVE is "false", do not proactively suggest gstack skills — only invoke
them when the user explicitly asks. The user opted out of proactive suggestions.
If output shows UPGRADE_AVAILABLE <old> <new>: read ~/.claude/skills/gstack/gstack-upgrade/SKILL.md and follow the "Inline upgrade flow" (auto-upgrade if configured, otherwise AskUserQuestion with 4 options, write snooze state if declined). If JUST_UPGRADED <from> <to>: tell user "Running gstack v{to} (just updated!)" and continue.
If LAKE_INTRO is no: Before continuing, introduce the Completeness Principle.
Tell the user: "gstack follows the Boil the Lake principle — always do the complete
thing when AI makes the marginal cost near-zero. Read more: https://garryslist.org/posts/boil-the-ocean"
Then offer to open the essay in their default browser:
open https://garryslist.org/posts/boil-the-ocean
touch ~/.gstack/.completeness-intro-seen
Only run open if the user says yes. Always run touch to mark as seen. This only happens once.
If TEL_PROMPTED is no AND LAKE_INTRO is yes: After the lake intro is handled,
ask the user about telemetry. Use AskUserQuestion:
Help gstack get better! Community mode shares usage data (which skills you use, how long
they take, crash info) with a stable device ID so we can track trends and fix bugs faster.
No code, file paths, or repo names are ever sent.
Change anytime with gstack-config set telemetry off.
Options:
- A) Help gstack get better! (recommended)
- B) No thanks
If A: run ~/.claude/skills/gstack/bin/gstack-config set telemetry community
If B: ask a follow-up AskUserQuestion:
How about anonymous mode? We just learn that someone used gstack — no unique ID,
no way to connect sessions. Just a counter that helps us know if anyone's out there.
Options:
- A) Sure, anonymous is fine
- B) No thanks, fully off
If B→A: run ~/.claude/skills/gstack/bin/gstack-config set telemetry anonymous
If B→B: run ~/.claude/skills/gstack/bin/gstack-config set telemetry off
Always run:
touch ~/.gstack/.telemetry-prompted
This only happens once. If TEL_PROMPTED is yes, skip this entirely.
AskUserQuestion Format
ALWAYS follow this structure for every AskUserQuestion call:
- Re-ground: State the project, the current branch (use the
_BRANCH value printed by the preamble — NOT any branch from conversation history or gitStatus), and the current plan/task. (1-2 sentences)
- Simplify: Explain the problem in plain English a smart 16-year-old could follow. No raw function names, no internal jargon, no implementation details. Use concrete examples and analogies. Say what it DOES, not what it's called.
- Recommend:
RECOMMENDATION: Choose [X] because [one-line reason] — always prefer the complete option over shortcuts (see Completeness Principle). Include Completeness: X/10 for each option. Calibration: 10 = complete implementation (all edge cases, full coverage), 7 = covers happy path but skips some edges, 3 = shortcut that defers significant work. If both options are 8+, pick the higher; if one is ≤5, flag it.
- Options: Lettered options:
A) ... B) ... C) ... — when an option involves effort, show both scales: (human: ~X / CC: ~Y)
Assume the user hasn't looked at this window in 20 minutes and doesn't have the code open. If you'd need to read the source to understand your own explanation, it's too complex.
Per-skill instructions may add additional formatting rules on top of this baseline.
Completeness Principle — Boil the Lake
AI-assisted coding makes the marginal cost of completeness near-zero. When you present options:
- If Option A is the complete implementation (full parity, all edge cases, 100% coverage) and Option B is a shortcut that saves modest effort — always recommend A. The delta between 80 lines and 150 lines is meaningless with CC+gstack. "Good enough" is the wrong instinct when "complete" costs minutes more.
- Lake vs. ocean: A "lake" is boilable — 100% test coverage for a module, full feature implementation, handling all edge cases, complete error paths. An "ocean" is not — rewriting an entire system from scratch, adding features to dependencies you don't control, multi-quarter platform migrations. Recommend boiling lakes. Flag oceans as out of scope.
- When estimating effort, always show both scales: human team time and CC+gstack time. The compression ratio varies by task type — use this reference:
| Task type | Human team | CC+gstack | Compression |
|---|
| Boilerplate / scaffolding | 2 days | 15 min | ~100x |
| Test writing | 1 day | 15 min | ~50x |
| Feature implementation | 1 week | 30 min | ~30x |
| Bug fix + regression test | 4 hours | 15 min | ~20x |
| Architecture / design | 2 days | 4 hours | ~5x |
| Research / exploration | 1 day | 3 hours | ~3x |
- This principle applies to test coverage, error handling, documentation, edge cases, and feature completeness. Don't skip the last 10% to "save time" — with AI, that 10% costs seconds.
Anti-patterns — DON'T do this:
- BAD: "Choose B — it covers 90% of the value with less code." (If A is only 70 lines more, choose A.)
- BAD: "We can skip edge case handling to save time." (Edge case handling costs minutes with CC.)
- BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
- BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
Repo Ownership Mode — See Something, Say Something
REPO_MODE from the preamble tells you who owns issues in this repo:
solo — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), investigate and offer to fix proactively. The solo dev is the only person who will fix it. Default to action.collaborative — Multiple active contributors. When you notice issues outside the branch's changes, flag them via AskUserQuestion — it may be someone else's responsibility. Default to asking, not fixing.unknown — Treat as collaborative (safer default — ask before fixing).
See Something, Say Something: Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
Never let a noticed issue silently pass. The whole point is proactive communication.
Search Before Building
Before building infrastructure, unfamiliar patterns, or anything the runtime might have a built-in — search first. Read ~/.claude/skills/gstack/ETHOS.md for the full philosophy.
Three layers of knowledge:
- Layer 1 (tried and true — in distribution). Don't reinvent the wheel. But the cost of checking is near-zero, and once in a while, questioning the tried-and-true is where brilliance occurs.
- Layer 2 (new and popular — search for these). But scrutinize: humans are subject to mania. Search results are inputs to your thinking, not answers.
- Layer 3 (first principles — prize these above all). Original observations derived from reasoning about the specific problem. The most valuable of all.
Eureka moment: When first-principles reasoning reveals conventional wisdom is wrong, name it:
"EUREKA: Everyone does X because [assumption]. But [evidence] shows this is wrong. Y is better because [reasoning]."
Log eureka moments:
jq -n --arg ts "$(date -u +%Y-%m-%dT%H:%M:%SZ)" --arg skill "SKILL_NAME" --arg branch "$(git branch --show-current 2>/dev/null)" --arg insight "ONE_LINE_SUMMARY" '{ts:$ts,skill:$skill,branch:$branch,insight:$insight}' >> ~/.gstack/analytics/eureka.jsonl 2>/dev/null || true
Replace SKILL_NAME and ONE_LINE_SUMMARY. Runs inline — don't stop the workflow.
WebSearch fallback: If WebSearch is unavailable, skip the search step and note: "Search unavailable — proceeding with in-distribution knowledge only."
Contributor Mode
If _CONTRIB is true: you are in contributor mode. You're a gstack user who also helps make it better.
At the end of each major workflow step (not after every single command), reflect on the gstack tooling you used. Rate your experience 0 to 10. If it wasn't a 10, think about why. If there is an obvious, actionable bug OR an insightful, interesting thing that could have been done better by gstack code or skill markdown — file a field report. Maybe our contributor will help make us better!
Calibration — this is the bar: For example, $B js "await fetch(...)" used to fail with SyntaxError: await is only valid in async functions because gstack didn't wrap expressions in async context. Small, but the input was reasonable and gstack should have handled it — that's the kind of thing worth filing. Things less consequential than this, ignore.
NOT worth filing: user's app bugs, network errors to user's URL, auth failures on user's site, user's own JS logic bugs.
To file: write ~/.gstack/contributor-logs/{slug}.md with all sections below (do not truncate — include every section through the Date/Version footer):
# {Title}
Hey gstack team — ran into this while using /{skill-name}:
**What I was trying to do:** {what the user/agent was attempting}
**What happened instead:** {what actually happened}
**My rating:** {0-10} — {one sentence on why it wasn't a 10}
## Steps to reproduce
1. {step}
## Raw output
{paste the actual error or unexpected output here}
## What would make this a 10
{one sentence: what gstack should have done differently}
**Date:** {YYYY-MM-DD} | **Version:** {gstack version} | **Skill:** /{skill}
Slug: lowercase, hyphens, max 60 chars (e.g. browse-js-no-await). Skip if file already exists. Max 3 reports per session. File inline and continue — don't stop the workflow. Tell user: "Filed gstack field report: {title}"
Completion Status Protocol
When completing a skill workflow, report status using one of:
- DONE — All steps completed successfully. Evidence provided for each claim.
- DONE_WITH_CONCERNS — Completed, but with issues the user should know about. List each concern.
- BLOCKED — Cannot proceed. State what is blocking and what was tried.
- NEEDS_CONTEXT — Missing information required to continue. State exactly what you need.
Escalation
It is always OK to stop and say "this is too hard for me" or "I'm not confident in this result."
Bad work is worse than no work. You will not be penalized for escalating.
- If you have attempted a task 3 times without success, STOP and escalate.
- If you are uncertain about a security-sensitive change, STOP and escalate.
- If the scope of work exceeds what you can verify, STOP and escalate.
Escalation format:
STATUS: BLOCKED | NEEDS_CONTEXT
REASON: [1-2 sentences]
ATTEMPTED: [what you tried]
RECOMMENDATION: [what the user should do next]
Telemetry (run last)
After the skill workflow completes (success, error, or abort), log the telemetry event.
Determine the skill name from the name: field in this file's YAML frontmatter.
Determine the outcome from the workflow result (success if completed normally, error
if it failed, abort if the user interrupted).
PLAN MODE EXCEPTION — ALWAYS RUN: This command writes telemetry to
~/.gstack/analytics/ (user config directory, not project files). The skill
preamble already writes to the same directory — this is the same pattern.
Skipping this command loses session duration and outcome data.
Run this bash:
_TEL_END=$(date +%s)
_TEL_DUR=$(( _TEL_END - _TEL_START ))
rm -f ~/.gstack/analytics/.pending-"$_SESSION_ID" 2>/dev/null || true
~/.claude/skills/gstack/bin/gstack-telemetry-log \
--skill "SKILL_NAME" --duration "$_TEL_DUR" --outcome "OUTCOME" \
--used-browse "USED_BROWSE" --session-id "$_SESSION_ID" 2>/dev/null &
Replace SKILL_NAME with the actual skill name from frontmatter, OUTCOME with
success/error/abort, and USED_BROWSE with true/false based on whether $B was used.
If you cannot determine the outcome, use "unknown". This runs in the background and
never blocks the user.
Plan Status Footer
When you are in plan mode and about to call ExitPlanMode:
- Check if the plan file already has a
## GSTACK REVIEW REPORT section.
- If it DOES — skip (a review skill already wrote a richer report).
- If it does NOT — run this command:
```bash
~/.claude/skills/gstack/bin/gstack-review-read
```
Then write a ## GSTACK REVIEW REPORT section to the end of the plan file:
- If the output contains review entries (JSONL lines before
---CONFIG---): format the
standard report table with runs/status/findings per skill, same format as the review
skills use.
- If the output is
NO_REVIEWS or empty: write this placeholder table:
```markdown
GSTACK REVIEW REPORT
| Review | Trigger | Why | Runs | Status | Findings |
|---|
| CEO Review | `/plan-ceo-review` | Scope & strategy | 0 | — | — |
| Codex Review | `/codex review` | Independent 2nd opinion | 0 | — | — |
| Eng Review | `/plan-eng-review` | Architecture & tests (required) | 0 | — | — |
| Design Review | `/plan-design-review` | UI/UX gaps | 0 | — | — |
VERDICT: NO REVIEWS YET — run `/autoplan` for full review pipeline, or individual reviews above.
```
PLAN MODE EXCEPTION — ALWAYS RUN: This writes to the plan file, which is the one
file you are allowed to edit in plan mode. The plan file review report is part of the
plan's living status.
browse: QA Testing & Dogfooding
Persistent headless Chromium. First call auto-starts (~3s), then ~100ms per command.
State persists between calls (cookies, tabs, login sessions).
SETUP (run this check BEFORE any browse command)
_ROOT=$(git rev-parse --show-toplevel 2>/dev/null)
B=""
[ -n "$_ROOT" ] && [ -x "$_ROOT/.claude/skills/gstack/browse/dist/browse" ] && B="$_ROOT/.claude/skills/gstack/browse/dist/browse"
[ -z "$B" ] && B=~/.claude/skills/gstack/browse/dist/browse
if [ -x "$B" ]; then
echo "READY: $B"
else
echo "NEEDS_SETUP"
fi
If NEEDS_SETUP:
- Tell the user: "gstack browse needs a one-time build (~10 seconds). OK to proceed?" Then STOP and wait.
- Run:
cd <SKILL_DIR> && ./setup
- If
bun is not installed: curl -fsSL https://bun.sh/install | bash
Core QA Patterns
1. Verify a page loads correctly
$B goto https://yourapp.com
$B text
$B console
$B network
$B is visible ".main-content"
2. Test a user flow
$B goto https://app.com/login
$B snapshot -i
$B fill @e3 "user@test.com"
$B fill @e4 "password"
$B click @e5
$B snapshot -D
$B is visible ".dashboard"
3. Verify an action worked
$B snapshot
$B click @e3
$B snapshot -D
4. Visual evidence for bug reports
$B snapshot -i -a -o /tmp/annotated.png
$B screenshot /tmp/bug.png
$B console
5. Find all clickable elements (including non-ARIA)
$B snapshot -C
$B click @c1
6. Assert element states
$B is visible ".modal"
$B is enabled "#submit-btn"
$B is disabled "#submit-btn"
$B is checked "#agree-checkbox"
$B is editable "#name-field"
$B is focused "#search-input"
$B js "document.body.textContent.includes('Success')"
7. Test responsive layouts
$B responsive /tmp/layout
$B viewport 375x812
$B screenshot /tmp/mobile.png
8. Test file uploads
$B upload "#file-input" /path/to/file.pdf
$B is visible ".upload-success"
9. Test dialogs
$B dialog-accept "yes"
$B click "#delete-button"
$B dialog
$B snapshot -D
10. Compare environments
$B diff https://staging.app.com https://prod.app.com
11. Show screenshots to the user
After $B screenshot, $B snapshot -a -o, or $B responsive, always use the Read tool on the output PNG(s) so the user can see them. Without this, screenshots are invisible.
User Handoff
When you hit something you can't handle in headless mode (CAPTCHA, complex auth, multi-factor
login), hand off to the user:
$B handoff "Stuck on CAPTCHA at login page"
$B resume
When to use handoff:
- CAPTCHAs or bot detection
- Multi-factor authentication (SMS, authenticator app)
- OAuth flows that require user interaction
- Complex interactions the AI can't handle after 3 attempts
The browser preserves all state (cookies, localStorage, tabs) across the handoff.
After resume, you get a fresh snapshot of wherever the user left off.
Snapshot Flags
The snapshot is your primary tool for understanding and interacting with pages.
-i --interactive Interactive elements only (buttons, links, inputs) with @e refs
-c --compact Compact (no empty structural nodes)
-d <N> --depth Limit tree depth (0 = root only, default: unlimited)
-s <sel> --selector Scope to CSS selector
-D --diff Unified diff against previous snapshot (first call stores baseline)
-a --annotate Annotated screenshot with red overlay boxes and ref labels
-o <path> --output Output path for annotated screenshot (default: <temp>/browse-annotated.png)
-C --cursor-interactive Cursor-interactive elements (@c refs — divs with pointer, onclick)
All flags can be combined freely. -o only applies when -a is also used.
Example: $B snapshot -i -a -C -o /tmp/annotated.png
Ref numbering: @e refs are assigned sequentially (@e1, @e2, ...) in tree order.
@c refs from -C are numbered separately (@c1, @c2, ...).
After snapshot, use @refs as selectors in any command:
$B click @e3 $B fill @e4 "value" $B hover @e1
$B html @e2 $B css @e5 "color" $B attrs @e6
$B click @c1
Output format: indented accessibility tree with @ref IDs, one element per line.
@e1 [heading] "Welcome" [level=1]
@e2 [textbox] "Email"
@e3 [button] "Submit"
Refs are invalidated on navigation — run snapshot again after goto.
Full Command List
Navigation
| Command | Description |
|---|
back | History back |
forward | History forward |
goto <url> | Navigate to URL |
reload | Reload page |
url | Print current URL |
Reading
| Command | Description |
|---|
accessibility | Full ARIA tree |
forms | Form fields as JSON |
html [selector] | innerHTML of selector (throws if not found), or full page HTML if no selector given |
links | All links as "text → href" |
text | Cleaned page text |
Interaction
| Command | Description |
|---|
click <sel> | Click element |
cookie <name>=<value> | Set cookie on current page domain |
cookie-import <json> | Import cookies from JSON file |
cookie-import-browser [browser] [--domain d] | Import cookies from Comet, Chrome, Arc, Brave, or Edge (opens picker, or use --domain for direct import) |
dialog-accept [text] | Auto-accept next alert/confirm/prompt. Optional text is sent as the prompt response |
dialog-dismiss | Auto-dismiss next dialog |
fill <sel> <val> | Fill input |
header <name>:<value> | Set custom request header (colon-separated, sensitive values auto-redacted) |
hover <sel> | Hover element |
press <key> | Press key — Enter, Tab, Escape, ArrowUp/Down/Left/Right, Backspace, Delete, Home, End, PageUp, PageDown, or modifiers like Shift+Enter |
scroll [sel] | Scroll element into view, or scroll to page bottom if no selector |
select <sel> <val> | Select dropdown option by value, label, or visible text |
type <text> | Type into focused element |
upload <sel> <file> [file2...] | Upload file(s) |
useragent <string> | Set user agent |
viewport <WxH> | Set viewport size |
| `wait <sel | --networkidle |
Inspection
| Command | Description |
|---|
| `attrs <sel | @ref>` |
| `console [--clear | --errors]` |
cookies | All cookies as JSON |
css <sel> <prop> | Computed CSS value |
dialog [--clear] | Dialog messages |
eval <file> | Run JavaScript from file and return result as string (path must be under /tmp or cwd) |
is <prop> <sel> | State check (visible/hidden/enabled/disabled/checked/editable/focused) |
js <expr> | Run JavaScript expression and return result as string |
network [--clear] | Network requests |
perf | Page load timings |
storage [set k v] | Read all localStorage + sessionStorage as JSON, or set to write localStorage |
Visual
| Command | Description |
|---|
diff <url1> <url2> | Text diff between pages |
pdf [path] | Save as PDF |
responsive [prefix] | Screenshots at mobile (375x812), tablet (768x1024), desktop (1280x720). Saves as {prefix}-mobile.png etc. |
| `screenshot [--viewport] [--clip x,y,w,h] [selector | @ref] [path]` |
Snapshot
| Command | Description |
|---|
snapshot [flags] | Accessibility tree with @e refs for element selection. Flags: -i interactive only, -c compact, -d N depth limit, -s sel scope, -D diff vs previous, -a annotated screenshot, -o path output, -C cursor-interactive @c refs |
Meta
| Command | Description |
|---|
chain | Run commands from JSON stdin. Format: [["cmd","arg1",...],...] |
Tabs
| Command | Description |
|---|
closetab [id] | Close tab |
newtab [url] | Open new tab |
tab <id> | Switch to tab |
tabs | List open tabs |
Server
| Command | Description |
|---|
handoff [message] | Open visible Chrome at current page for user takeover |
restart | Restart server |
resume | Re-snapshot after user takeover, return control to AI |
status | Health check |
stop | Shutdown server |
