# Gemmein (npm · @gemmein/mcp)

Gemmein docs, API reference, error explainers and a live integration check for coding agents.

- Trust score: 69/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-26

## Components

- npm · `@gemmein/mcp`: 69/100 (this document), [markdown](https://verifymcp.io/servers/com-gemmein-mcp/gemmein-mcp.md), [page](https://verifymcp.io/servers/com-gemmein-mcp/gemmein-mcp)

## Channel facts

- Registry: `npm`
- Package: `@gemmein/mcp`
- Version: `0.10.0`
- 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 2026-09-26.

- **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.
  - 31 of 96 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 45/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 0 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 69/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 1720 tokens (~191/item across 9 items; 9 tools + 0 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**: 97/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 92% 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 9 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 10 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 Gemmein MCP server?

Gemmein runs locally as an npm package, launched with npx -y @gemmein/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 com-gemmein-mcp -- npx -y @gemmein/mcp
```

### Cursor

```json
{
  "mcpServers": {
    "com-gemmein-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@gemmein/mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "com-gemmein-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@gemmein/mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add com-gemmein-mcp -- npx -y @gemmein/mcp
```

### opencode

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

### OpenClaw

```bash
openclaw mcp add com-gemmein-mcp --command npx --arg -y --arg @gemmein/mcp
```

### Hermes

```yaml
mcp_servers:
  com-gemmein-mcp:
    command: "npx"
    args: ["-y", "@gemmein/mcp"]
```

### Netclaw

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

### Vellum

```bash
assistant mcp add com-gemmein-mcp -t stdio -c npx -a -y @gemmein/mcp
```

### Other

```json
{
  "mcpServers": {
    "com-gemmein-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@gemmein/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.

### 2026-09-25 (score 69)

First indexed and scored.

## MCP tools (9)

### `guide` (~242 tokens)

Call this FIRST — before any install, account, or code — when your human asks to build an app on Gemmein, to move an existing app onto it, or whether their app can use it at all. The guide (llms.txt) opens with two doors — starting from an idea with nothing built yet, or already holding an app — and both lead to the same fit assessment: the in-scope map, the out-of-scope list (each item downgrades the verdict; none may be approximated), and the three verdicts you deliver to your human before installing anything — FITS, FITS EXCEPT <named gaps>, or DOESN'T FIT. After the verdict it is the full build contract: auth flow, the seven collection safety rules, record shapes, links/expand, uploads, contention patterns, payments (g.subscriptions.checkout / g.payments.buy), drafts, error philosophy, pricing. It also teaches the keys (server · CLI · sync), `gemmein sync` and `sync --live`, go-live and promotion, relays, AI tools defined on the server and run with `g.ai.run`, and credits.

### `reference` (~70 tokens)

Reach for this while WRITING code against @gemmein/sdk: every method, exact signature, return shape, and the stable error-code table (REFERENCE.md). Use `guide` for how the model works and whether the app fits at all; use `search_docs` when you need one fact from either document.

### `search_docs` (~112 tokens)

Use when one question comes up mid-build ('keyed create', 'ifVersion', 'addressed', 'expand') and reading a full document would waste context. Searches the guide and the API reference; returns matching passages with 3 lines of context either side, at most 6 match blocks per document. Not the tool for the fit verdict — search finds what the docs say, not what Gemmein refuses to support; call `guide` for that.

Input parameters:

- `query` (string, required): term or phrase to find

### `explain_rule` (~156 tokens)

Call while DESIGNING a collection — which rule fits this data? — or when a rule refuses something at runtime. One of the seven rules (private, shared, admin_write, public_read, community, addressed, direct) returns its exact access contract, what it is right for, and the mistakes that leak data. Call with no rule for the all-seven cheat-sheet plus the cross-cutting law, including what NO rule supports (team/group/workspace scope, per-user visibility inside a rule) — if the app needs those shapes, that is a fit gap to report to your human, never something to approximate with client-side filtering.

Input parameters:

- `rule` (string): the rule to explain; omit for the all-rules cheat-sheet

### `explain_error` (~112 tokens)

Call the moment a GemmeinError reaches you (err.code: conflict, forbidden, unknown_collection, invalid_shape, html_not_allowed, …): what the code means and the exact next step — including whether the refusal is final (a forbidden repeats on retry; fix the approach, not the request). Parsed from the installed API reference, so codes match the SDK version the app runs. Call with no code to list every stable code.

Input parameters:

- `code` (string): the err.code to explain; omit to list all

### `validate_collection_name` (~100 tokens)

Run at PLANNING time on every collection name you intend to use, before any g.collection(name) call is written. The naming law: lowercase letters, numbers, underscores; starts with a letter; 2-63 characters. A bad name throws from g.collection(name) before any network call — at module load that blanks the whole app with no console error. An invalid name comes back with a suggested fix.

Input parameters:

- `name` (string, required)

### `reaffirm_template` (~104 tokens)

Fetch this when you wire up the app's CI, or when you hand the finished app to your human: reaffirm.mjs, the ready-to-edit harness that re-proves the app's boundaries against live Gemmein on every deploy (also shipped inside the @gemmein/sdk package). Copy it next to the app, set the CONFIG block, run it in CI. For a one-off check right now, call check_integration — the same checks with no file to install.

### `explain_relay` (~253 tokens)

Call while WRITING or FIXING gemmein/relays/<name>.json — before `gemmein sync` carries it to the cloud. A relay is one trigger (receiver: a provider's webhook; schedule: a clock; data_change: a record changing) and up to ten actions in Gemmein's own verbs (write_record, grant_access, revoke_access, grant_credits, email_person, call_url, fulfil_product, refund_product, grant_plan, revoke_plan) — Gemmein runs it: receives the event, maps the fields, authorises, carries out the action. Pass the definition JSON; the answer is the English sentence the dashboard shows ("When gocardless-paid receives an event where event_type is confirmed → grant Pro, email the person, call https://…") or the ONE refusal sentence the cloud would answer, naming the field and the fix. Offline and read-only: nothing is created. Two checks run only in the cloud and are stated in the answer (the API's own hosts; the address's resolved network at call time).

Input parameters:

- `definition` (object, required): the relay definition — the contents of gemmein/relays/<name>.json ({ name, trigger, actions })

### `check_integration` (~354 tokens)

Call after wiring the app to Gemmein and before telling your human it is done — and again before go-live. Runs the reaffirm boundary checks live against the caller's own app; returns structured pass/fail (structuredContent: checks, notes, failedCount, passed). Tier A (public pk_ key only): the collection name is valid, anonymous reads and writes of a private collection are refused, an optional public collection reads as its rule intends — safe against any environment, live included. Tier B (add the sk_dev secret key): proves one user cannot read another's private records, using two throwaway test sessions in the DEV environment. sk_live is refused by design — never pass a live secret to any tool; dev and live enforce the same rules, so isolation proven in dev holds in live. The only writes anywhere are Tier B's own probe records in the caller's dev environment, deleted at the end of the check. A failed check means the app's assumptions drifted from its rules — fix before shipping.

Input parameters:

- `apiUrl` (string): optional: API base URL override (local/dev API); omit for production Gemmein
- `privateCollection` (string, required): a collection with the `private` rule
- `publicCollection` (string): optional: a community/public_read collection to confirm anonymous readability
- `publicKey` (string, required): the app's public pk_ key
- `secretKey` (string): optional: the sk_dev secret key — enables Tier B isolation proof (sk_live is refused)
- `testUsers` (array): optional: the two Tier-B test emails (default reaffirm-a/b@test.dev)
- `timeoutMs` (number): overall time budget, default 30000

## Diagnostics

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

## Score history

- 2026-09-26: 69
- 2026-09-25: 69

## Common questions

### What is the Gemmein MCP server?

Gemmein is an MCP server listed in the public MCP registry as com.gemmein/mcp. Gemmein docs, API reference, error explainers and a live integration check for coding agents. This page covers its npm package (@gemmein/mcp).

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

Gemmein scores 69 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 26 September 2026. It declares no install or post-install scripts. 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 Gemmein MCP server expose?

Gemmein exposes 9 tools: guide, reference, search_docs, explain_rule, explain_error, and 4 more. Their descriptions and schemas cost roughly 1,503 tokens of context every time the server is loaded.

### Is the Gemmein MCP server still maintained?

Gemmein is still listed as active in the MCP registry. We last reached this channel on 26 September 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 Gemmein MCP server under?

Gemmein 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/@gemmein/mcp
- Socket report: https://socket.dev/npm/package/@gemmein/mcp
- Repository: https://github.com/gemmeinhq/gemmein-release
- Website: https://gemmein.com/
- Changelog RSS feed: https://verifymcp.io/servers/com-gemmein-mcp/gemmein-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/com-gemmein-mcp/gemmein-mcp.json
- HTML version of this page: https://verifymcp.io/servers/com-gemmein-mcp/gemmein-mcp