Tap

Taprun

The action layer your agent drives in your own logged-in browser — for the exception-heavy, compliance-critical last 20% that clean APIs can't reach. Compiled once, replayed forever at zero LLM tokens.

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Your agent's closed-loop action layer for the browser — the login-gated, exception-heavy, compliance-critical last 20% that clean APIs and cloud agents can't reach. Driven in your own Chrome, captured once, replayed forever at zero LLM tokens.

As APIs get walled off and metered, the work that survives lives behind logins, OTP walls, and human-gesture gates — the exceptions, approvals, and compliance steps a cloud agent architecturally can't touch. Taprun is the action layer for exactly that: your agent drives your real, already-logged-in Chrome, closes the loop (act → verify the effect → re-run on drift), and hands you a deterministic replay you own.

Every other browser agent re-runs a live LLM — and re-burns tokens — on every execution. Taprun's AI agent inspects the page once and emits a deterministic .flow.json program; every replay after that is pure data dispatch — same result every call, $0 in tokens, no agent in the loop. It runs in your real Chrome, so cookies and login sessions stay on your machine by architecture. tap verify catches breakage before your data goes stale.

Works with Claude Code, CodeBuddy, Cursor, Cline, Windsurf, and any MCP host — install straight from the chat window. Forge a tap from any URL on demand — no catalog needed.

Capture: AI inspects the site → compiles a .flow.json program     (one-time cost)

Run: The program executes instantly, same result every time ($0, zero AI) Verify: tap verify checks the snapshot equivalence predicate (catches drift) Repair: re-run capture against the same site/name; the next (only when needed) verify rebaselines after human review

How Taprun Compares

Get Started

1. Attach to your agent — from the chat window

Claude Code / CodeBuddy — paste two lines into the chat, nothing else:

/plugin marketplace add LeonTing1010/taprun

/plugin install tap@taprun

That installs the Taprun MCP server plus the skills that teach your agent when to use it and the hook that routes walled fetches to Taprun — no terminal, no config file. (CodeBuddy wires plugin MCP servers at startup only, so fully restart it once after installing; Claude Code picks them up with /reload-plugins.)

Any other MCP host (Cursor · VS Code · Claude Desktop) — one command writes the config for you:

npx -y @taprun/cli embed cursor   # or: vscode | claude-desktop | claude-code | codebuddy | qwen

The binary self-copies to ~/.tap/bin and your agent's MCP config is written. Re-check anytime with tap embed --verify.

Using a coding agent that isn't in that list? tap embed targets are *data, not code*: drop a row into ~/.tap/embed-targets.json and the new agent works immediately — no engine release. Each row names one of four install *kinds* (cc-plugin for Claude-Code-plugin hosts, cli-mcp-add for CLIs with a mcp add, ide-deeplink, desktop-bundle), e.g. [{"id":"kode","kind":"cc-plugin","display":"Kode CLI","tier":1,"cli":"kode"}]. Same doctrine as the rest of Taprun — the engine stays closed and mechanical; you extend it in local data.

Now pick your runtime — **the extension is only needed to reuse your *live* logged-in Chrome:**

• Public pages / open APIs / CI — nothing more to install. The MCP server runs over npx; you're done. Append --no-extension for a fully in-chat Playwright runtime with its own isolated profile (no browser gesture, no click).
• Logged-in sites (your bank / internal dashboard / Xiaohongshu / Zhihu) — just tell your agent "set up tap for logged-in sites" right in the chat. The tap-setup skill drives the whole bridge from the chat: it materializes the stable binary (from the engine npx already downloaded — no second download) and registers the native-messaging manifest, then opens the extension page. The single [Add to Chrome](https://chromewebstore.google.com/detail/tap/llcidejeoobdegbkolbjhfoeckphldce) click is the only step that isn't a chat action — it *is* the trust gate that lets Taprun reuse your existing login, and the in-flight call resumes automatically once it lands.
• Claude Desktop: download tap.mcpb and double-click.

Other install paths (brew · curl · manual MCP JSON · raw binaries)

brew install LeonTing1010/tap/taprun            # Homebrew (macOS / Linux)

curl -fsSL https://taprun.dev/install.sh | sh # permanent binary npx -y @taprun/cli --version # zero-install (any Node host)

Manual MCP config, if you'd rather write it yourself:

{ "mcpServers": { "tap": { "command": "npx", "args": ["-y", "@taprun/cli", "mcp", "stdio"] } } }

2. Prove it works (~2 minutes, no login)

Run the first entry of the claims ledger — the exact verification its nightly CI runs:

mkdir -p ~/.tap/flows/github

curl -fsSL https://raw.githubusercontent.com/LeonTing1010/tap-skills/main/claims/2026-07-11-github-trending-has-no-api/plan.json \ -o ~/.tap/flows/github/trending-no-api.flow.json tap github/trending-no-api

"state": "committed" plus today's trending repos at zero tokens = your install works and the claim holds.

3. Forge your own

tap capture https://news.ycombinator.com hn/front --intent "front-page stories with points"

tap hn/front # replay forever, $0

Or just ask your AI agent:

You:   What's trending on GitHub today?

Agent: Here are today's top repos — React compiler hit 734 stars...

You: Capture a tap for Douban top 250 movies Agent: Done. Run tap douban/top250 anytime — $0 per run.

Optional: Drive the binary from your own code (TypeScript / Python)

Skip MCP — call the tap binary from your own loop:

tap capture <url> hackernews/top --intent "front-page top stories"

tap hackernews/top --args '{}' # JSON-on-stdout, exit 0 on success tap verify hackernews/top # 3-arm verdict (live / drifted / unreachable)

The CLI emits ToolResult envelopes as JSON — same shape the MCP surface returns — so any language with a subprocess library can drive it. See tap --help for the full verb list.

Have an existing Playwright / Puppeteer / Stagehand script?

Don't rewrite. Convert with one of the open-source adapters — drop your existing source in, get a Taprun-compatible .flow.json plan out:

# Existing Playwright script (47M weekly npm downloads — most likely the one you have)

npm install @taprun/from-playwright @taprun/spec node -e "import('@taprun/from-playwright').then(m => console.log(m.playwrightToTap(require('fs').readFileSync('tests/login.spec.ts','utf8'), {site:'example', name:'login'})))"

Or scaffold a new starter from scratch

npx create-tap-script github/trending https://github.com/trending

The format itself is documented at @taprun/spec — the public protocol surface package: TypeScript types for the v2 Plan (18-op closed union + discriminated read/write Plan union) + JSON Schema 2020-12 with $id resolvable at taprun.dev/spec/plan-v1/schema.json, bidirectionally drift-guarded against the TS types. Third-party tooling (IDE $schema autocomplete, ajv-equivalent validators in Python/Ruby/Go, governance layers, alternative runtimes, MCP hosts with plan-aware permission scoping) builds against this package without depending on the proprietary Taprun engine. Plan-v1 reference: taprun.dev/spec/plan-v1. Source for all five packages: packages/ (see packages/README.md for the workspace overview).

What Can You Do?

Read — Extract data from any website

tap reddit/hot                   # Reddit front page

tap bilibili/trending # Bilibili trending tap arxiv/search --keyword "LLM"