# Vaers (npm · @pipeworx/mcp-vaers)

VAERS (Vaccine Adverse Event Reporting System) — report counts by vaccine, manufacturer, symptom…

- Trust score: 82/100 (high trust)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- remote · `gateway.pipeworx.io`: 77/100, [markdown](https://verifymcp.io/servers/pipeworx-io-vaers/vaers-mcp.md), [page](https://verifymcp.io/servers/pipeworx-io-vaers/vaers-mcp)
- npm · `@pipeworx/mcp-vaers`: 82/100 (this document), [markdown](https://verifymcp.io/servers/pipeworx-io-vaers/pipeworx-mcp-vaers.md), [page](https://verifymcp.io/servers/pipeworx-io-vaers/pipeworx-mcp-vaers)

## Channel facts

- Registry: `npm`
- Package: `@pipeworx/mcp-vaers`
- Version: `0.2.0`
- 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 2026-11-05.

- **Supply Chain Security**: 100/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - No install/post-install scripts declared.
  - No production dependencies, so there is no dependency health to assess.
- **Provenance & Transparency**: 97/100
  - Source repository is publicly reachable at the declared URL.
  - Cryptographically verified build provenance (signed, bound to pipeworx-io/mcp-vaers).
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 7 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 62/100
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 834 tokens (~278/item across 3 items; 3 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 23/100
  - Stability observed for 7 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **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 3 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 4 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.

## Install

### How do I install the Vaers MCP server?

Vaers runs locally as an npm package, launched with npx -y @pipeworx/mcp-vaers. 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 pipeworx-io-vaers -- npx -y @pipeworx/mcp-vaers
```

### Cursor

```json
{
  "mcpServers": {
    "pipeworx-io-vaers": {
      "command": "npx",
      "args": [
        "-y",
        "@pipeworx/mcp-vaers"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "pipeworx-io-vaers": {
      "command": "npx",
      "args": [
        "-y",
        "@pipeworx/mcp-vaers"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add pipeworx-io-vaers -- npx -y @pipeworx/mcp-vaers
```

### opencode

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

### OpenClaw

```bash
openclaw mcp add pipeworx-io-vaers --command npx --arg -y --arg @pipeworx/mcp-vaers
```

### Hermes

```yaml
mcp_servers:
  pipeworx-io-vaers:
    command: "npx"
    args: ["-y", "@pipeworx/mcp-vaers"]
```

### Netclaw

```json
{
  "McpServers": {
    "pipeworx-io-vaers": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "@pipeworx/mcp-vaers"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add pipeworx-io-vaers -t stdio -c npx -a -y @pipeworx/mcp-vaers
```

### Other

```json
{
  "mcpServers": {
    "pipeworx-io-vaers": {
      "command": "npx",
      "args": [
        "-y",
        "@pipeworx/mcp-vaers"
      ]
    }
  }
}
```

## 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.

### 2026-11-05 (score 82, +1)

No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-03 (score 81, +1)

No change was recorded against any check on this day. Stability & Change Management went from 13 to 17. That category is still filling its 30-day observation window: 4 days of observed history at the previous scan, 5 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-31 (score 80, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-30 (score 79, 0)

- [functional regression] Security disclosure: unverified → fail

### 2026-10-29 (score 79)

First indexed and scored.

## MCP tools (3)

### `vaers_events_by_vaccine` (~357 tokens)

VAERS report counts and severity breakdown (died / life-threatening / hospitalized / disabled / ER visit) by vaccine, for the requested year range. Pass `vaccine` as the VAERS vax_type code (e.g. "COVID19", "FLU4", "HPV9", "VARCEL", "MMR") to get that vaccine's counts; omit it to browse the top vaccines ranked by report volume, which doubles as a way to discover valid codes. Optionally narrow to one `manufacturer` (substring match, e.g. "PFIZER", "MODERNA"). Answers "how many VAERS reports mention the COVID-19 vaccine", "which vaccine has the most reported deaths in VAERS", "Pfizer vs Moderna VAERS report counts". IMPORTANT: a report count is NOT evidence the vaccine caused the event — VAERS accepts any report from anyone, unverified. Every response carries the CDC/FDA disclaimer and `is_causal: false`. This never returns a single report's free text.

Input parameters:

- `limit` (number|string): Max rows (1-200, default 20).
- `manufacturer` (string): Manufacturer substring, e.g. "PFIZER", "MODERNA", "MERCK". Optional.
- `vaccine` (string): VAERS vax_type code, e.g. "COVID19", "FLU4", "HPV9", "MMR", "VARCEL". Omit to see the top vaccines by report count.
- `year_from` (number|string): Earliest report-received year to include (data covers 1990-2026).
- `year_to` (number|string): Latest report-received year to include.

### `vaers_events_by_symptom` (~329 tokens)

VAERS report counts by symptom (MedDRA preferred term), optionally filtered to one vaccine and/or year range. Pass `symptom` as a substring (e.g. "headache", "anaphyla", "myocarditis") to count how often it was reported; omit it to see the most-reported symptoms overall (optionally within one vaccine). Answers "how many VAERS reports mention myocarditis after the COVID-19 vaccine", "most commonly reported symptoms for the flu vaccine in 2022". Counts are MENTIONS — a report naming several symptoms and/or several vaccines contributes to each combination, so this is not a count of unique reports. IMPORTANT: a symptom being reported alongside a vaccine is NOT evidence the vaccine caused it — VAERS accepts any report from anyone, unverified. Every response carries the CDC/FDA disclaimer and `is_causal: false`. This never returns a single report's free text.

Input parameters:

- `limit` (number|string): Max rows (1-200, default 20).
- `symptom` (string): Symptom substring (MedDRA preferred term), e.g. "headache", "anaphyla", "myocarditis". Omit to see the top symptoms.
- `vaccine` (string): VAERS vax_type code to narrow to one vaccine, e.g. "COVID19". Optional.
- `year_from` (number|string): Earliest report-received year to include (data covers 1990-2026).
- `year_to` (number|string): Latest report-received year to include.

### `vaers_coverage` (~96 tokens)

What this VAERS pack currently holds: total unique reports, the year range covered, how many distinct vaccine types and manufacturers, and when the seed was last (re)loaded — refresh is a manual re-download of the CDC/FDA data files, not a live feed, so check this before relying on recency. Also returns the top 5 vaccines by report volume as a starting point for vaers_events_by_vaccine.

## Diagnostics

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

## Score history

- 2026-11-05: 82
- 2026-11-04: 81
- 2026-11-03: 81
- 2026-11-02: 80
- 2026-11-01: 80
- 2026-10-31: 80
- 2026-10-30: 79
- 2026-10-29: 79

## Common questions

### What is the Vaers MCP server?

Vaers is an MCP server listed in the public MCP registry as io.github.pipeworx-io/vaers. VAERS (Vaccine Adverse Event Reporting System), report counts by vaccine, manufacturer, symptom… This page covers its npm package (@pipeworx/mcp-vaers).

### Is the Vaers MCP server safe to use?

Vaers scores 82 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 5 November 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 Vaers MCP server expose?

Vaers exposes 3 tools: vaers_events_by_vaccine, vaers_events_by_symptom, vaers_coverage. Their descriptions and schemas cost roughly 782 tokens of context every time the server is loaded.

### Is the Vaers MCP server still maintained?

Vaers is still listed as active in the MCP registry. We last reached this channel on 5 November 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 Vaers MCP server under?

Vaers 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/@pipeworx/mcp-vaers
- Socket report: https://socket.dev/npm/package/@pipeworx/mcp-vaers
- Repository: https://github.com/pipeworx-io/mcp-vaers
- Website: https://pipeworx.io/packs/vaers
- Changelog RSS feed: https://verifymcp.io/servers/pipeworx-io-vaers/pipeworx-mcp-vaers.xml
- Changelog JSON feed: https://verifymcp.io/servers/pipeworx-io-vaers/pipeworx-mcp-vaers.json
- HTML version of this page: https://verifymcp.io/servers/pipeworx-io-vaers/pipeworx-mcp-vaers