# ESP32 Simulator (npm · esp32sim-mcp)

Boot and test ESP32 firmware in a local emulator: UART asserts, buttons, virtual WiFi, screenshots.

- Trust score: 81/100 (high trust)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-25

## Components

- npm · `esp32sim-mcp`: 81/100 (this document), [markdown](https://verifymcp.io/servers/stramanu-esp32sim-mcp/esp32sim-mcp.md), [page](https://verifymcp.io/servers/stramanu-esp32sim-mcp/esp32sim-mcp)

## Channel facts

- Registry: `npm`
- Package: `esp32sim-mcp`
- Version: `0.2.6`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-10-25.

- **Supply Chain Security**: 98/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - No install/post-install scripts declared.
  - 30 of 96 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 100/100
  - Source repository is publicly reachable at the declared URL.
  - Cryptographically verified build provenance (signed, bound to stramanu/esp32sim-mcp).
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 5 days ago).
  - Publishes a security disclosure policy (SECURITY.md).
- **Schema Quality & AI Usability**: 74/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 1574 tokens (~196/item across 8 items; 6 tools + 2 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 0/100
  - Stability not yet verified: not enough scan history yet (needs a 30-day window).
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 6 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 7 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

**Unverified: 1 category.** A category scored 0 because we could not verify it: a data source with nothing on this package, evidence we could not reach, or a check we could not run. We only credit what we can confirm.

## Install

### How do I install the ESP32 Simulator MCP server?

ESP32 Simulator runs locally as an npm package, launched with npx -y esp32sim-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add stramanu-esp32sim-mcp -- npx -y esp32sim-mcp
```

### Cursor

```json
{
  "mcpServers": {
    "stramanu-esp32sim-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "esp32sim-mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "stramanu-esp32sim-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "esp32sim-mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add stramanu-esp32sim-mcp -- npx -y esp32sim-mcp
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "stramanu-esp32sim-mcp": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "esp32sim-mcp"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add stramanu-esp32sim-mcp --command npx --arg -y --arg esp32sim-mcp
```

### Hermes

```yaml
mcp_servers:
  stramanu-esp32sim-mcp:
    command: "npx"
    args: ["-y", "esp32sim-mcp"]
```

### Netclaw

```json
{
  "McpServers": {
    "stramanu-esp32sim-mcp": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "esp32sim-mcp"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add stramanu-esp32sim-mcp -t stdio -c npx -a -y esp32sim-mcp
```

### Other

```json
{
  "mcpServers": {
    "stramanu-esp32sim-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "esp32sim-mcp"
      ]
    }
  }
}
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-10-20 (score 81, +15)

- [security improvement] Malware scan: unverified → pass

### 2026-10-19 (score 66)

First indexed and scored.

## MCP tools (6)

### `sim_run` (~436 tokens)

Boots and simulates ESP32 firmware in a local emulator without hardware. Captures UART logs, FreeRTOS asserts, memory faults, and stop reason.

Input parameters:

- `appBin` (string): Direct path to the application binary (.bin).
- `board` (string): Board model: S3 'atech14' (default), 'waveshare-lcd4b', 'waveshare-amoled18-v2', 'waveshare-cam'; C6 'waveshare-c6-lcd147'; ESP32 'ttgo-tdisplay', 'esp32dev-loopback'; 'none' for a bare module. Omit…
- `bootloaderBin` (string): Direct path to bootloader.bin (needed with appBin for a real ROM boot).
- `chip` (string): Target chip family. Default is s3 (ESP32-S3).
- `console` (string): Console source to capture (default: both = UART0 + USB-Serial/JTAG). Lines ESP-IDF mirrors on both consoles are shown once.
- `maxSeconds` (number): Maximum emulated time in seconds (default: 10s). Emulation usually runs faster than real time.
- `projectDir` (string): Path to the ESP-IDF project root or build folder. If omitted, uses current working directory.
- `ptableBin` (string): Direct path to partition-table.bin (needed with appBin for a real ROM boot).
- `stopAfterExceptions` (number): Stop after N CPU exceptions (unset by default). Counts every exception, including the window overflow/underflow ones Xtensa firmware takes constantly, so it is a debugging aid, not a crash detector.…
- `wifi` (string): Attach a virtual access point with DHCP/DNS/NAT. Spec like 'ssid=demo,psk=secret' (keys: ssid, psk, chan, bssid), or a bare SSID for an open network. Station gets 10.0.2.15.

### `sim_script` (~381 tokens)

Simulates hardware interactions (button presses, GPIO levels, rotary encoder turns, touch, UART/console input) at specific emulated timestamps, capturing interactive firmware behavior.

Input parameters:

- `appBin` (string): Direct path to the application binary (.bin).
- `board` (string): Board model: S3 'atech14' (default), 'waveshare-lcd4b', 'waveshare-amoled18-v2', 'waveshare-cam'; C6 'waveshare-c6-lcd147'; ESP32 'ttgo-tdisplay', 'esp32dev-loopback'; 'none' for a bare module. Omit…
- `bootloaderBin` (string): Direct path to bootloader.bin (needed with appBin for a real ROM boot).
- `chip` (string): Target chip family. Default is s3 (ESP32-S3).
- `events` (array): Host actions at emulated times.
- `maxSeconds` (number): Total simulation duration in seconds (default 15).
- `projectDir` (string): Path to the ESP-IDF project root or build folder. If omitted, uses current working directory.
- `ptableBin` (string): Direct path to partition-table.bin (needed with appBin for a real ROM boot).
- `scriptContent` (string): Raw esp32sim script text instead of events (e.g. "1.5 press btn1 150\n3.0 stop").
- `wifi` (string): Attach a virtual access point with DHCP/DNS/NAT. Spec like 'ssid=demo,psk=secret' (keys: ssid, psk, chan, bssid), or a bare SSID for an open network. Station gets 10.0.2.15.

### `sim_expect` (~415 tokens)

Runs firmware in simulation and asserts that specific text or regex patterns appear on UART. Ideal for automated unit & integration testing in a Red-Green-Refactor agent loop.

Input parameters:

- `appBin` (string): Direct path to the application binary (.bin).
- `board` (string): Board model: S3 'atech14' (default), 'waveshare-lcd4b', 'waveshare-amoled18-v2', 'waveshare-cam'; C6 'waveshare-c6-lcd147'; ESP32 'ttgo-tdisplay', 'esp32dev-loopback'; 'none' for a bare module. Omit…
- `bootloaderBin` (string): Direct path to bootloader.bin (needed with appBin for a real ROM boot).
- `chip` (string): Target chip family. Default is s3 (ESP32-S3).
- `events` (array): Optional interaction events before checking patterns.
- `maxSeconds` (number): Max emulated seconds to wait for patterns (default 10).
- `ordered` (boolean): Whether patterns must appear in exact chronological sequence (default: true).
- `patterns` (array, required): Expected console output. Plain text matches as a substring of a line ("Counter: 5"); write a regular expression between slashes ("/Counter: \\d+/", "/wifi.*connected/i").
- `projectDir` (string): Path to the ESP-IDF project root or build folder. If omitted, uses current working directory.
- `ptableBin` (string): Direct path to partition-table.bin (needed with appBin for a real ROM boot).
- `wifi` (string): Attach a virtual access point with DHCP/DNS/NAT. Spec like 'ssid=demo,psk=secret' (keys: ssid, psk, chan, bssid), or a bare SSID for an open network. Station gets 10.0.2.15.

### `sim_screenshot` (~222 tokens)

Captures a snapshot image of the virtual LCD/TFT display buffer at a specified emulated time.

Input parameters:

- `appBin` (string): Direct path to the application binary (.bin).
- `board` (string): Board with a display: 'atech14', 'waveshare-lcd4b', 'waveshare-amoled18-v2' (S3), 'waveshare-c6-lcd147' (C6), 'ttgo-tdisplay' (ESP32).
- `bootloaderBin` (string): Direct path to bootloader.bin (needed with appBin for a real ROM boot).
- `chip` (string): Target chip family. Default is s3 (ESP32-S3).
- `projectDir` (string): Path to the ESP-IDF project root or build folder. If omitted, uses current working directory.
- `ptableBin` (string): Direct path to partition-table.bin (needed with appBin for a real ROM boot).
- `timeSeconds` (number): Emulated second at which to take the screenshot.

### `sim_list_boards` (~40 tokens)

Returns the catalogue of all supported ESP32 chips, boards, displays, peripherals and capabilities.

Input parameters:

- `chip` (string): Filter boards by chip family.

### `sim_doctor` (~33 tokens)

Validates local environment: checks if esp32sim binary is installed, checks Rust/Cargo, and provides setup instructions.

## Diagnostics

Captured diagnostic sections: Provenance, Dependencies. The full working is on the page: https://verifymcp.io/servers/stramanu-esp32sim-mcp/esp32sim-mcp#diagnostics

## Score history

- 2026-10-25: 81
- 2026-10-24: 81
- 2026-10-23: 81
- 2026-10-22: 81
- 2026-10-21: 81
- 2026-10-20: 81
- 2026-10-19: 66

## Common questions

### What is the ESP32 Simulator MCP server?

ESP32 Simulator is an MCP server listed in the public MCP registry as io.github.stramanu/esp32sim-mcp. Boot and test ESP32 firmware in a local emulator: UART asserts, buttons, virtual WiFi, screenshots. This page covers its npm package (esp32sim-mcp).

### Is the ESP32 Simulator MCP server safe to use?

ESP32 Simulator scores 81 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 25 October 2026. It declares no install or post-install scripts. Its build provenance is signed and verified. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the ESP32 Simulator MCP server expose?

ESP32 Simulator exposes 6 tools: sim_run, sim_script, sim_expect, sim_screenshot, sim_list_boards, sim_doctor. Their descriptions and schemas cost roughly 1,527 tokens of context every time the server is loaded.

### Is the ESP32 Simulator MCP server still maintained?

ESP32 Simulator is still listed as active in the MCP registry. We last reached this channel on 25 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

### What licence is the ESP32 Simulator MCP server under?

ESP32 Simulator declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

## Links

- npm package: https://www.npmjs.com/package/esp32sim-mcp
- Socket report: https://socket.dev/npm/package/esp32sim-mcp
- Repository: https://github.com/stramanu/esp32sim-mcp
- Changelog RSS feed: https://verifymcp.io/servers/stramanu-esp32sim-mcp/esp32sim-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/stramanu-esp32sim-mcp/esp32sim-mcp.json
- HTML version of this page: https://verifymcp.io/servers/stramanu-esp32sim-mcp/esp32sim-mcp