# npx-vibe [Health: Active] **Category:** 💻 Developer Tools **Repository:** https://github.com/Devrajsinh-Jhala/NPM-Vibe-check **GitHub Stars:** 0 **npm Downloads (last month):** 794 **Views:** 0 **Installs:** 0 **Upvotes:** 0 **Directory Page:** https://allmcps.com/mcp/npx-vibe ## Description Read-only npm package and project dependency preflight tools for AI applications. ## Claude Desktop Quick Installation Install path detected from listing signals. Uses `npx` (confidence: high): ```json "mcpServers": { "npx-vibe": { "command": "npx", "args": ["-y","npx-vibe"] } } ``` ## Documentation & README # npx-vibe [![npm version](https://img.shields.io/npm/v/npx-vibe.svg?color=22d3ee)](https://www.npmjs.com/package/npx-vibe) [![npm weekly downloads](https://img.shields.io/npm/dw/npx-vibe.svg?color=34d399)](https://www.npmjs.com/package/npx-vibe) [![npm total downloads](https://img.shields.io/npm/dt/npx-vibe.svg?color=a78bfa)](https://www.npmjs.com/package/npx-vibe) [![CI](https://github.com/Devrajsinh-Jhala/NPM-Vibe-check/actions/workflows/ci.yml/badge.svg?branch=master)](https://github.com/Devrajsinh-Jhala/NPM-Vibe-check/actions/workflows/ci.yml) [![Node.js](https://img.shields.io/node/v/npx-vibe.svg)](https://www.npmjs.com/package/npx-vibe) [![License: MIT](https://img.shields.io/npm/l/npx-vibe.svg)](./LICENSE) **Evidence-first safety checks for npm packages and project dependencies before developers, coding agents, or MCP clients execute them.** `npx-vibe` resolves packages from the public npm registry, downloads and verifies their tarballs without executing them, inspects install-time code, and prints clear **Proceed**, **Caution**, or **Block** verdicts. Use it for one-off `npx` commands or scan an existing project's direct dependencies. The default scan is deterministic, local, and requires no account or API key. AI review is optional, opt-in, and lets you choose an exact model or a maintained `fast`, `balanced`, or `strong` profile. Version 1.5 also ships a zero-dependency MCP server with read-only package, project, and model-catalog tools. - [npm package](https://www.npmjs.com/package/npx-vibe) - [Official MCP Registry entry](https://registry.modelcontextprotocol.io/v0.1/servers?search=io.github.Devrajsinh-Jhala%2Fnpx-vibe) - [Live website](https://devrajsinh-jhala.github.io/NPM-Vibe-check/) - [GitHub repository](https://github.com/Devrajsinh-Jhala/NPM-Vibe-check) - [Security policy](./SECURITY.md) - [Changelog](./CHANGELOG.md) - [Release process](./RELEASING.md) ## Live adoption The [project website](https://devrajsinh-jhala.github.io/NPM-Vibe-check/) displays the current seven-day download total directly from npm's public download API: - [weekly total](https://api.npmjs.org/downloads/point/last-week/npx-vibe) - [daily seven-day range](https://api.npmjs.org/downloads/range/last-week/npx-vibe) The counter is live rather than hard-coded, and the site links to the source data. npm download counts measure package fetches, not unique users. They are momentum signals—not proof of package safety or quality—but they show that the package is being discovered and installed. ## Quick start Review a package without executing it: ```bash npx npx-vibe --check esbuild ``` Use it as a guarded replacement for `npx`: ```bash npx npx-vibe cowsay -- hello from npx-vibe ``` Or install the command globally: ```bash npm install -g npx-vibe npx-vibe --check ``` Scan an existing project's direct dependencies: ```bash npx npx-vibe --project . ``` Give a coding agent a stable, read-only result: ```bash npx --yes npx-vibe@latest --agent esbuild npx --yes npx-vibe@latest --agent --project . ``` Or connect the native MCP server: ```bash npx --yes npx-vibe@latest --mcp ``` ## Use npx-vibe with coding agents `--agent` turns the scanner into a predictable machine interface. It implies check-only mode, writes only JSON to stdout, disables terminal color and local review-memory writes, and never executes package code. Operational failures are JSON too, so an agent can fail closed instead of interpreting partial terminal output. Install the portable Agent Skill for Codex, Claude Code, Cursor, VS Code, and other compatible agents: ```bash npx skills add Devrajsinh-Jhala/NPM-Vibe-check --skill npx-vibe -g ``` The skill tells an agent to preflight unfamiliar packages before `npx`, `npm exec`, or dependency installation and then apply the normalized decision: | `decision.action` | Required behavior | | --- | --- | | `continue` | Continue only with the package action the user already requested | | `review` | Pause, summarize source evidence, and request human approval | | `stop` | Do not install or execute the package | | `retry` | The scan is incomplete; report the error and do not infer safety | Example envelope: ```json { "schemaVersion": 1, "tool": { "name": "npx-vibe", "version": "1.5.1" }, "kind": "package-scan", "status": "complete", "decision": { "verdict": "caution", "riskScore": 43, "action": "review", "exitCode": 2, "mayContinue": false, "safeToExecute": false, "requiresApproval": true, "requiresHumanReview": true, "blocked": false, "mustStop": false }, "subject": { "type": "package", "name": "esbuild", "requested": "latest", "version": "0.28.1" }, "report": {} } ``` The complete deterministic report remains under `report`. Require `schemaVersion === 1`, `status === "complete"`, and `decision.mayContinue === true` before continuing automatically. The outer `npx --yes` only suppresses npm's download prompt; agent mode rejects npx-vibe's execution flags such as `--force` and `--yes`. AI remains off by default in agent mode. If a user explicitly requests model interpretation, use a provider-specific environment variable and add `--ai online --provider `; never place a key in a generated command. ## Connect npx-vibe through MCP Version 1.5 includes a read-only [Model Context Protocol](https://modelcontextprotocol.io/) server over stdio. It gives MCP-compatible AI applications a native tool surface without teaching them to parse terminal text or construct shell commands. Add this server configuration to an MCP client that supports local stdio servers: ```json { "mcpServers": { "npx-vibe": { "command": "npx", "args": ["--yes", "npx-vibe@latest", "--mcp"] } } } ``` Global installations can use `npx-vibe-mcp` as the command with no arguments. Run `npx npx-vibe --mcp --help` for server-specific help. The server exposes three schema-backed tools: | MCP tool | Purpose | | --- | --- | | `scan_package` | Resolve, verify, and inspect one public npm package without executing it | | `scan_project` | Review direct registry dependencies from a project manifest or lockfile | | `list_models` | Return the bundled provider and model-profile catalog without a network request | Scan results return the same versioned decision contract in both `structuredContent` and a JSON text block for client compatibility. The tools are annotated read-only and non-destructive. `review` still requires human approval, while `stop`, `retry`, and MCP tool errors fail closed. AI remains off unless a tool call explicitly selects it. API keys are intentionally excluded from MCP tool arguments: configure provider-specific environment variables on the MCP server process so credentials do not enter prompts or tool history. `npx-vibe@1.5.1` is [active in the official MCP Registry](https://registry.modelcontextprotocol.io/v0.1/servers?search=io.github.Devrajsinh-Jhala%2Fnpx-vibe) as `io.github.Devrajsinh-Jhala/npx-vibe`. Registry clients can resolve the verified npm package and start its local stdio server with `--mcp`. ## Why developers use it Running `npx some-package` can download code and execute a package binary immediately. Packages may also declare lifecycle scripts that run during installation. `npx-vibe` inserts a visible checkpoint before execution: 1. Resolve the exact npm package version. 2. Fetch registry, download, maintainer, publisher, and repository context. 3. Download the tarball without running package code. 4. Verify npm integrity metadata and inspect bounded source files. 5. Show matched evidence and a risk verdict. 6. Execute only after the verdict allows it. For an existing app, `--project` repeats the same read-only review across direct registry dependencies and aggregates the result. This makes the check useful in local development and pull-request CI, not only before an unfamiliar `npx` command. By default, execution uses npm with install scripts ignored. Use `--allow-install-scripts` only when you intentionally want reviewed root lifecycle scripts to run. ## Evidence, not mystery scores Every deterministic source finding includes the matched line and a bounded excerpt. Registry popularity is displayed separately as context and never overrides suspicious code. Local review memory is keyed by the verified package integrity—not merely its name or version. The example below mirrors a real scan; registry dates and download counts naturally change over time. ```text $ npx npx-vibe --check esbuild ! npx-vibe: Caution risk 43/100 esbuild@0.28.1 Downloads: 241,858,907/week Package age: 3132d Version age: 12d Install hooks: postinstall Established signals: long registry history, high weekly adoption, linked GitHub repository Registry popularity and age provide context, but never override code findings. Review memory: unchanged tarball since 2026-06-25; previous Caution 43/100. AI review: skipped (Heuristic-only mode; AI was not requested.) Findings: - MEDIUM lifecycle_hook in package.json postinstall runs: node install.js Evidence: postinstall: node install.js - MEDIUM network_and_shell in install.js Code combines network access with shell execution. Evidence line 147: fetch(url) ... child_process.execSync(...) Action: review recommended before execution. ``` A popular package can still receive **Caution** when it performs sensitive install-time behavior. That is intentional: maturity is useful context, not a security exemption. When AI is explicitly enabled, the resolved provider and model are visible in the result. This example is adapted from the successful Gemini 3.5 Flash run on June 25, 2026; model wording can vary: ```text $ npx npx-vibe --check --ai online --provider gemini --model-profile balanced esbuild ! npx-vibe: Caution risk 43/100 esbuild@0.28.1 Install hooks: postinstall AI review: Gemini gemini-3.5-flash [balanced] (high confidence) AI evidence: 0 source-backed findings AI interpretation: The selected install script appears to resolve a platform-specific binary. No additional source-backed credential access, obfuscation, or persistence finding was identified, but the deterministic install-time network and process evidence remains. Action: review recommended before execution. ``` ## What it checks | Area | Signals | | --- | --- | | Registry context | package age, version age, weekly downloads, maintainers, publisher, license, deprecation | | Install behavior | `preinstall`, `install`, `postinstall`, `prepare`, and related script targets | | Tarball safety | npm integrity verification, unsafe paths, escaping symlinks, archive size and entry limits | | Source behavior | secret/environment access, network calls, shell execution, external payloads, obfuscation, persistence, mining indicators | | Dependency metadata | remote Git/HTTP/file dependency protocols and lockfile install-script indicators | | Repository context | GitHub repository, stars, last update, last push, and latest commit | | Review memory | verified integrity match, previous verdict, selected-file changes, lifecycle-hook changes, and finding deltas | | Optional AI | local Ollama or supported online providers, used only after explicit opt-in and a heuristic trigger | ## Built for repeated use `npx-vibe` always performs a fresh registry lookup, tarball download, integrity verification, and deterministic scan. Local review memory adds comparison context after those checks: ```text Review memory: unchanged tarball since 2026-06-25; previous Caution 43/100. ``` When the integrity changes: ```text Version comparison: 0.28.1 → current; integrity changed. 2 selected files changed; findings +1/-0; install hooks unchanged. ``` The history file stores package versions, integrity hashes, selected-file hashes, finding identifiers, verdicts, and model metadata. It does not store package source, API keys, environment values, or local project files. The default location is `~/.npx-vibe/reviews.json`. ## Verdicts | Verdict | Meaning | Check-mode exit code | | --- | --- | --- | | **Proceed** | No meaningful deterministic risk signal was found | `0` | | **Caution** | Reviewable behavior or incomplete context requires human judgment | `2` | | **Block** | Critical behavior or a high-risk review result was detected | `3` | | Operational error | Registry, network, input, or internal failure | `1` | A verdict is a decision aid, not proof that a package is safe or malicious. ## Usage ```text npx-vibe [options] [-- package arguments] npx-vibe --project [options] npx-vibe --mcp ``` Common commands: ```bash # Heuristic-only review; do not execute npx npx-vibe --check # Machine-readable output npx npx-vibe --json # Versioned, fail-closed JSON for coding agents npx --yes npx-vibe@latest --agent # Review, then execute when permitted npx npx-vibe -- # Select one executable from a package with multiple binaries npx npx-vibe --bin tsc typescript -- --version # Scan production and optional dependencies from this project npx npx-vibe --project . # Include direct development dependencies npx npx-vibe --project . --include-dev # Machine-readable project report npx npx-vibe --project . --json # Agent-ready project report npx --yes npx-vibe@latest --agent --project . # Start the MCP server over stdio npx --yes npx-vibe@latest --mcp # Execute a Caution verdict without prompting npx npx-vibe --yes # Execute a Block verdict intentionally npx npx-vibe --force ``` Useful options: ```text --check --json --agent --mcp --project --include-dev --ci --concurrency <1-8> --ai-limit <0-100> --yes, -y --force --bin --ai off|auto|online|ollama --provider auto|openai|anthropic|gemini|openrouter|groq|together|custom --models --model-profile fast|balanced|strong --model --api-key --api-url --ollama-url --ollama-model --registry --age-days --downloads --caution-score <0-100> --block-score <0-100> --allow-install-scripts --no-history --history-file --no-color ``` Run `npx npx-vibe --help` for the complete CLI reference. ## Project dependency scans Project mode turns the one-package review into a repeatable dependency preflight: ```bash npx npx-vibe --project . ``` It reads `package.json` and, when present, `package-lock.json` locally. Exact direct versions from npm lockfiles are preferred over version ranges. By default it scans `dependencies` and `optionalDependencies`; add `--include-dev` for `devDependencies`. ```text ! npx-vibe project: Caution highest risk 43/100 my-app@1.0.0 Scanned: 12/12 direct dependencies Proceed: 11 Caution: 1 Block: 0 Scope: dependencies + optionalDependencies Resolution: exact versions from package-lock.json when available AI review: off (heuristic-only) Packages: - CAUTION 43/100 esbuild@0.28.1 young_version, lifecycle_hook, network_and_shell No dependency or package code was executed during this project scan. Action: review the flagged dependencies and their evidence individually. ``` The workflow is deliberately bounded: - Only direct registry dependencies are scanned; transitive dependency graph analysis is not claimed. - Workspace, local, alias, URL, and Git specs are reported as skipped rather than uploaded or resolved through another trust path. - Heuristic-only scans use three concurrent reviews by default (`--concurrency 1-8`). - If AI is opted in, reviews are sequential and only heuristic-triggered packages call the model. The default budget is three calls (`--ai-limit 0-100`). - `package.json` and `package-lock.json` are never sent to an AI provider. Optional online AI receives only bounded files selected from the downloaded registry package. This is autonomous triage rather than autonomous execution: discover, resolve, verify, inspect, escalate when requested, and aggregate. It never installs dependencies or edits the project. ## AI is optional and opt-in Ambient keys such as `OPENAI_API_KEY` or `GEMINI_API_KEY` do **not** activate AI in the default mode. > **Important:** Do not paste long-lived API keys into screenshots, issues, chat messages, or shared terminal recordings. Revoke any exposed key immediately. ```bash npx npx-vibe # heuristic-only default npx npx-vibe --provider gemini --api-key # direct-key shortcut npx npx-vibe --ai online # use an explicitly configured online provider npx npx-vibe --ai auto # detect configured provider or local Ollama npx npx-vibe --ai ollama # local Ollama ``` Provider-specific keys are read only after `--ai online` or `--ai auto` is selected: ```bash OPENAI_API_KEY=... npx npx-vibe --ai online ANTHROPIC_API_KEY=... npx npx-vibe --ai online GEMINI_API_KEY=... npx npx-vibe --ai online OPENROUTER_API_KEY=... npx npx-vibe --ai online GROQ_API_KEY=... npx npx-vibe --ai online TOGETHER_API_KEY=... npx npx-vibe --ai online ``` Provider-specific environment variables are the safest and most reliable option because they avoid provider guessing and keep secrets out of shell history. Recognizable direct-key formats can be routed automatically, but ambiguous formats stop locally and ask for `--provider` rather than sending a credential to a guessed service. Google introduced new Gemini authorization keys in June 2026. `npx-vibe 1.2.0` recognizes both the newer authorization-key family and traditional Google API keys, and sends Gemini credentials using Google's documented `x-goog-api-key` header. PowerShell example: ```powershell $env:GEMINI_API_KEY="" npx npx-vibe --ai online --provider gemini esbuild Remove-Item Env:GEMINI_API_KEY ``` Direct-key example when you intentionally want to specify the provider: ```powershell npx npx-vibe --provider gemini --api-key "" esbuild ``` If automatic routing cannot confidently identify a direct key, `npx-vibe` exits locally with instructions to add `--provider`. It does not try the key against OpenAI or any other guessed endpoint. Custom OpenAI-compatible endpoint: ```bash npx npx-vibe --ai online \ --provider custom \ --api-url https://models.example.com/v1/chat/completions \ --api-key \ --model \ ``` Online AI receives bounded package metadata, deterministic findings, install scripts, and selected files from the downloaded package tarball. It does not receive your project files, shell history, npm tokens, or environment-variable values. AI findings are checked against the inspected source before they are displayed as evidence. A model finding records its file, line, exact excerpt, and rationale. Unsupported model claims are omitted from the source-backed findings section, and an unsupported AI recommendation cannot independently produce a Block verdict. ### Choose a model without memorizing provider catalogs The default online profile is `balanced`. It aims for a practical mix of review quality, latency, and cost. You can inspect the complete bundled mapping without configuring a key: ```bash npx npx-vibe --models ``` Choose a simple profile: ```bash npx npx-vibe --check --ai online --provider anthropic --model-profile fast npx npx-vibe --check --ai online --provider openai --model-profile balanced npx npx-vibe --check --ai online --provider gemini --model-profile strong ``` Or pin any provider-supported model: ```bash npx npx-vibe --check --ai online --provider gemini --model gemini-3.5-flash ``` Bundled recommendations, verified **June 25, 2026**: | Provider | Fast | Balanced (default) | Strong | | --- | --- | --- | --- | | OpenAI | `gpt-5.4-nano` | `gpt-5.4-mini` | `gpt-5.5` | | Anthropic | `claude-haiku-4-5` | `claude-sonnet-4-6` | `claude-opus-4-8` | | Gemini | `gemini-3.1-flash-lite` | `gemini-3.5-flash` | `gemini-3.5-flash` | | OpenRouter | `openrouter/auto` | `openrouter/auto` | `openrouter/auto` | | Groq | `openai/gpt-oss-20b` | `openai/gpt-oss-120b` | `openai/gpt-oss-120b` | | Together AI | `Qwen/Qwen3.5-9B` | `Qwen/Qwen3.5-9B` | `deepseek-ai/DeepSeek-V4-Pro` | Official references: [OpenAI models](https://developers.openai.com/api/docs/guides/latest-model), [Anthropic models](https://platform.claude.com/docs/en/about-claude/models/overview), [Gemini models](https://ai.google.dev/gemini-api/docs/models), [OpenRouter Auto](https://openrouter.ai/docs/guides/routing/routers/auto-router), [Groq models](https://console.groq.com/docs/models), and [Together serverless models](https://docs.together.ai/docs/serverless/models). Provider catalogs change independently of `npx-vibe`. The resolved model is always printed, `--model` always wins, and `--models` shows the recommendations bundled with your installed release. Custom OpenAI-compatible endpoints require an explicit `--model`. ## Automation, agents, and CI Use JSON plus exit codes in local automation: ```bash npx npx-vibe --json > npx-vibe-report.json npx npx-vibe --project . --json > npx-vibe-project-report.json ``` Use the versioned agent envelope when another tool or coding agent owns the decision loop: ```bash npx --yes npx-vibe@latest --agent npx --yes npx-vibe@latest --agent --project . ``` Agent mode keeps stdout machine-readable for successful, incomplete, and failed scans. It is deliberately incompatible with `--force`, npx-vibe's `--yes`, `--allow-install-scripts`, and package execution arguments. For GitHub Actions, `--ci` emits a warning for each Caution result, an error for each Block or operational failure, and writes a package table to the job summary: ```yaml name: Dependency preflight on: pull_request: workflow_dispatch: jobs: npx-vibe: runs-on: ubuntu-latest permissions: contents: read steps: - uses: actions/checkout@v4 - uses: actions/setup-node@v4 with: node-version: 20 - run: npx --yes npx-vibe@1.5.1 --project . --include-dev --ci ``` Project mode preserves the normal exit contract: `0` Proceed, `2` Caution, `3` Block, and `1` for an incomplete scan caused by an operational error. `--ci` and `--json` are intentionally separate so JSON output remains valid. The repository tests Node.js 20, 22, and 24 across Linux, Windows, and macOS. CI also packs the npm tarball, installs it into a clean temporary consumer project, and exercises the shipped CLI and MCP handshake from the exact artifact users receive. The tag-driven release workflow is prepared for [npm trusted publishing](https://docs.npmjs.com/trusted-publishers/) and `npm publish --provenance`. Configure the trusted publisher once, then push a version tag to publish without storing a long-lived npm token. See [RELEASING.md](./RELEASING.md). ## Configuration ```bash NPX_VIBE_AI=off NPX_VIBE_PROVIDER=auto NPX_VIBE_API_KEY=... NPX_VIBE_API_URL=https://api.openai.com/v1/chat/completions NPX_VIBE_MODEL_PROFILE=balanced NPX_VIBE_MODEL=gpt-5.4-mini NPX_VIBE_HISTORY=on NPX_VIBE_HISTORY_FILE=~/.npx-vibe/reviews.json NPX_VIBE_OLLAMA_URL=http://127.0.0.1:11434 NPX_VIBE_OLLAMA_MODEL=qwen2.5-coder NPX_VIBE_AGE_DAYS=14 NPX_VIBE_DOWNLOADS=1000 NPX_VIBE_CAUTION_SCORE=40 NPX_VIBE_BLOCK_SCORE=70 NPX_VIBE_CONCURRENCY=3 NPX_VIBE_AI_LIMIT=3 ``` ## Supported scope `npx-vibe` supports public npm registry package names, scoped packages, dist-tags, exact versions, common semver ranges, and direct dependency discovery from npm package manifests and lockfiles. It intentionally rejects local paths, arbitrary tarball URLs, Git URLs, and non-registry project dependencies to keep the trust boundary narrow. Node.js 20 or newer is required. The project is tested on current Windows, macOS, and Linux GitHub-hosted runners. ## Security boundary `npx-vibe` is a pre-execution risk scanner. It is not a sandbox, antivirus engine, formal audit, or guarantee of safety. A package may hide behavior in unselected files, dependencies, runtime branches, native code, or remote responses. - Treat **Proceed** as a useful signal, not proof. - Read the evidence for **Caution** findings. - Do not bypass **Block** unless you understand the behavior. - Report vulnerabilities privately through [SECURITY.md](./SECURITY.md). - Report noisy findings with the [false-positive template](https://github.com/Devrajsinh-Jhala/NPM-Vibe-check/issues/new?template=false-positive.yml). ## Contributing Contributions that improve detection quality, evidence, compatibility, or false-positive handling are welcome. See [CONTRIBUTING.md](./CONTRIBUTING.md). ## License MIT © Devrajsinh Jhala