The feedback loop for AI-assisted building
AI can build a prototype in an hour.
Turning feedback into action is still the slow part.
Spikes is a feedback tool for AI-assisted development. It lets reviewers leave targeted feedback directly on web pages — no screenshots, no "that button over there", no lost context.
Click any element. Rate it. Comment. Spikes captures the exact CSS selector, bounding box, and page context. Your AI agent gets structured JSON it can act on immediately.
No accounts required. No build step. Works on file://, localhost, anywhere.
curl -fsSL https://spikes.sh/install.sh | sh
# Or: cargo install spikesspikes inject ./mockups/ # Injects widget script tag
spikes serve # http://localhost:3847spikes list # See all feedback
spikes list --json # Feed to your agent
spikes list --rating no # Find problems
spikes hotspots # Elements with most feedback
spikes resolve <id> # Mark items done| Command | Description |
|---|---|
spikes init |
Create .spikes/ directory with config |
spikes list |
List feedback (--json, --page, --reviewer, --rating, --unresolved) |
spikes show <id> |
Show single spike details |
spikes export |
Export to JSON/CSV/JSONL/Cursor/Claude context |
spikes hotspots |
Elements with most feedback |
spikes reviewers |
List all reviewers |
spikes inject <dir> |
Add/remove widget from HTML files |
spikes serve |
Local dev server (--port, --marked, --cors-allow-origin) |
spikes mcp serve |
Start MCP server for AI agent integration |
spikes pull/push/sync |
Sync with remote endpoint |
spikes share <dir> |
Upload to spikes.sh for instant sharing |
spikes login/logout/whoami |
Authentication management |
spikes upgrade/billing |
Pro tier subscription via Stripe |
spikes deploy cloudflare |
Scaffold self-hosted Worker + D1 |
All commands support --json for scripting. See full CLI reference.
Spikes speaks agent natively. Your AI coding assistant can read, write, and manage feedback without ever leaving its workflow.
npx spikes-mcp # Zero-install MCP server — just works
# or: spikes mcp serve # If you have the CLI installedspikes mcp serve starts a Model Context Protocol server that exposes 9 tools:
| Tool | Purpose |
|---|---|
get_spikes |
List feedback with filters (page, rating, unresolved) |
get_element_feedback |
Get feedback for a specific CSS selector |
get_hotspots |
Find elements with the most feedback |
submit_spike |
Create feedback programmatically |
resolve_spike |
Mark feedback as addressed |
delete_spike |
Remove a spike |
create_share |
Upload files, get a shareable URL |
list_shares |
See your active shares |
get_usage |
Check usage stats, limits, and spend |
Supports stdio and HTTP transports, local and remote data modes:
spikes mcp serve # stdio, local JSONL
spikes mcp serve --remote # stdio, hosted API
spikes mcp serve --transport http --port 3848 # HTTP for sandboxed agentsAgents get their own identity. No email, no magic link, no human step:
spikes auth create-key --name "my-agent" # → sk_spikes_...
spikes auth list-keys # See all keys
spikes auth revoke-key <key_id> # RevokeKeys support read/write/full scopes and optional budget caps.
Consumption-based pricing for agent-scale usage. Pay per spike, not per seat:
spikes usage # See current spend and limitsBudget enforcement returns 429 BUDGET_EXCEEDED when caps are hit — agents can check before they burn.
Export structured markdown optimized for agent consumption:
spikes export --format cursor-context > cursor-feedback.md
spikes export --format claude-context > claude-feedback.md- llms.txt — All 9 MCP tools, parameters, agent quickstart
- agents.md — Machine-readable landing page for agents
- Smithery — Listed in the MCP server registry
spikes mcp install— Generates config for Claude Desktop / Cursor
Full details: llms.txt · agents.md
Gate CI on feedback quality. The spikes-action fails builds when unresolved negative feedback exceeds your threshold.
name: CI
on: [push, pull_request]
jobs:
feedback-gate:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
- uses: moritzbierling/spikes/action@v0.3.1
with:
threshold: 0 # Fail if any blocking spikes
ignore-paths: "" # Optional: pages to ignore
require-resolution: falseSee action/README.md for full documentation.
<script src="https://spikes.sh/spikes.js"
data-project="my-app"
data-position="bottom-right"
data-color="#e74c3c"
data-theme="dark"
data-reviewer="Pat"
data-endpoint="https://api.example.com/spikes"
data-collect-email="true"
data-admin="true">
</script>| Attribute | Description | Default |
|---|---|---|
data-project |
Group feedback by project key | location.hostname |
data-position |
Button corner: bottom-right, bottom-left, top-right, top-left |
bottom-right |
data-color |
Accent color (any CSS color) | #e74c3c |
data-theme |
Modal theme: dark or light |
dark |
data-reviewer |
Pre-set reviewer name | (prompts user) |
data-endpoint |
Backend URL for multi-reviewer sync | (local only) |
data-collect-email |
Show email field in prompt | false |
data-admin |
Enable review mode features | false |
data-offset-x/y |
Button offset from edge | — |
See Widget Attributes Reference for complete documentation.
Spikes has three components that work together or standalone:
┌─────────────┐ ┌─────────────┐ ┌─────────────┐
│ CLI │────▶│ Widget │◄────│ Worker │
│ (Rust) │ │ (Vanilla │ │ (Cloudflare │
│ │ │ JS) │ │ + D1) │
└─────────────┘ └─────────────┘ └─────────────┘
│ │
│ spikes.sh (hosted) │
└────────────────────────────────────────────┘
CLI — Rust binary for local development, spike management, and deployment. Stores spikes in ~/.local/share/spikes/.
Widget — 14KB gzipped vanilla JS. Captures element selectors, bounding boxes, ratings, and comments. Works offline via localStorage.
Worker — Optional Cloudflare Worker + D1 backend for multi-reviewer sync, sharing, and hosted deployments. Lives in spikes-hosted/.
cd cli
cargo build --release
cargo test # 160+ tests
cargo run -- --helpcd widget
# Edit src/spikes.js
# Test by running: spikes serve from the project rootcd ../spikes-hosted/worker
npm install
npx vitest run # 284+ tests
npx wrangler devWant your own backend? One command:
spikes deploy cloudflare # Creates spikes-worker/ directory
cd spikes-worker && npx wrangler deploySee Self-Hosting Guide for full setup with D1 database, authentication, and Stripe billing integration.
- Security: PBKDF2 password hashing, path traversal fixes, XSS protection
- Auth: Magic link authentication (no passwords to forget)
- Billing: Stripe integration with Pro tier support
- Testing: 160 CLI tests + 284 worker tests
- Architecture: Modular worker with clean separation of concerns
- CI/CD: Automated testing and deployment pipelines
- CLI Reference — Complete command documentation
- Widget Attributes — All configuration options
- Self-Hosting Guide — Deploy your own backend
- API Reference — REST API documentation
- Rollback Guide — Emergency procedures
| Zero friction | One script tag, no signup required, no build step |
| Works anywhere | file://, localhost, any domain |
| Precise | Element-level feedback with exact CSS selectors |
| Agent-native | JSON everywhere, pipes, queryable CLI |
| Your infrastructure | Self-host or use hosted — your choice |
| Tiny | Widget is 14KB gzipped |
| Private | No tracking, your data stays yours |
No accounts required to start. Login when you need Pro features.
| Free | Pro | |
|---|---|---|
| Price | $0 forever | Pay what you can |
| Shares | 5 | Unlimited |
| Spikes per share | 1,000 | Unlimited |
| Widget + CLI | Full | Full |
| Self-hosting | Yes | Yes |
| Password protection | — | Yes |
| Webhooks | — | Yes |
| Badge removal | — | Yes |
MIT licensed. Payment is appreciation, not access.
spikes upgrade when you're ready. No pressure.