Gemmein
NPM · @GEMMEIN/MCP · SCANNED SEP 26
Gemmein docs, API reference, error explainers and a live integration check for coding agents.
Available components
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. How we score → Why this is hard to score →
Supply Chain Security98
- No malware found by supply-chain analysis.Pass
- No known CVEs affecting this package version or its production dependencies.Pass
- No install/post-install scripts declared.Pass
- 31 of 96 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency45
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 0 days ago).Pass
- Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability69
- AI-judged instruction clarity (excellent).Pass
- 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. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management0
- Stability not yet verified: not enough scan history yet (needs a 30-day window).Unverified
Tool Coverage97
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 92% of tool parameters carry a description.Partial
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 9 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 10 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
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.
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.
npm · @gemmein/mcp
claude mcp add com-gemmein-mcp -- npx -y @gemmein/mcp
{
"mcpServers": {
"com-gemmein-mcp": {
"command": "npx",
"args": [
"-y",
"@gemmein/mcp"
]
}
}
} {
"servers": {
"com-gemmein-mcp": {
"command": "npx",
"args": [
"-y",
"@gemmein/mcp"
]
}
}
} codex mcp add com-gemmein-mcp -- npx -y @gemmein/mcp
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"com-gemmein-mcp": {
"type": "local",
"command": [
"npx",
"-y",
"@gemmein/mcp"
],
"enabled": true
}
}
} openclaw mcp add com-gemmein-mcp --command npx --arg -y --arg @gemmein/mcp
mcp_servers:
com-gemmein-mcp:
command: "npx"
args: ["-y", "@gemmein/mcp"] {
"McpServers": {
"com-gemmein-mcp": {
"Transport": "stdio",
"Command": "npx",
"Arguments": [
"-y",
"@gemmein/mcp"
]
}
}
} assistant mcp add com-gemmein-mcp -t stdio -c npx -a -y @gemmein/mcp
{
"mcpServers": {
"com-gemmein-mcp": {
"command": "npx",
"args": [
"-y",
"@gemmein/mcp"
]
}
}
} Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 25 Sept 26 69
First indexed and scored.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 26 Sept 2026 · Analysed npm/@gemmein/mcp@0.10.0
Provenance No attestation
The registry publishes no build provenance for this version, so there is nothing to verify.
| Result | No attestation |
|---|---|
| Ecosystem | npm |
Background: How many MCP packages publish verified provenance →
Dependencies 96 packages
| Packages resolved | 96 |
|---|---|
| Stale | 31 |
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
check_integration ~354
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.
| Name | Type | Req | Description |
|---|---|---|---|
| apiUrl | string | – | optional: API base URL override (local/dev API); omit for production Gemmein |
| privateCollection | string | yes | a collection with the `private` rule |
| publicCollection | string | – | optional: a community/public_read collection to confirm anonymous readability |
| publicKey | string | yes | 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 |
No output schema declared.
No examples provided.
explain_error ~112
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.
| Name | Type | Req | Description |
|---|---|---|---|
| code | string | – | the err.code to explain; omit to list all |
No output schema declared.
No examples provided.
explain_relay ~253
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).
| Name | Type | Req | Description |
|---|---|---|---|
| definition | object | yes | the relay definition — the contents of gemmein/relays/<name>.json ({ name, trigger, actions }) |
No output schema declared.
No examples provided.
explain_rule ~156
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.
| Name | Type | Req | Description |
|---|---|---|---|
| rule | string | – | the rule to explain; omit for the all-rules cheat-sheet |
No output schema declared.
No examples provided.
guide ~242
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.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
reaffirm_template ~104
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.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
reference ~70
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.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
search_docs ~112
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.
| Name | Type | Req | Description |
|---|---|---|---|
| query | string | yes | term or phrase to find |
No output schema declared.
No examples provided.
validate_collection_name ~100
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.
| Name | Type | Req | Description |
|---|---|---|---|
| name | string | yes | – |
No output schema declared.
No examples provided.
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.