io.github.lukasschwarz/elster-mcp-server

NPM · ELSTER-MCP-SERVER · SCANNED AUG 3

Drive the German tax portal ELSTER via Puppeteer: submit UStVA, prepare EUER/ESt, sync inbox.

Available components

+10 this week 53 53 Trust /100

Trust breakdown (6 categories)

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 →

Supply Chain Security70

No malware found by supply-chain analysis.Pass
CVE check failed: a known high-severity CVE affects @modelcontextprotocol/sdk 0.6.1, a direct dependency. A fixed version is available. View diagnostics → Fail
No install/post-install scripts declared.Pass
Only part of the dependency tree could be resolved (115 of 116), so this covers what we could see, not the whole tree. 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 36 days ago).Pass
Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail

Schema Quality & AI Usability71

AI-judged instruction clarity (good).Pass
Tool/resource definitions use about 1020 tokens (~72/item across 14 items; 14 tools + 0 resources), lean.Pass
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 Coverage79

100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
37% of tool parameters carry a description.Partial

Capabilities20

Spec-recency check failed: implements MCP spec 2024-11-05; the latest is 2026-07-28. See how to fix → Fail

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

Add this component to your MCP client. Where a client-specific snippet is available, pick your client below and copy it straight into your config; otherwise use the connection detail shown.

npm · elster-mcp-server

Claude Codex opencode OpenClaw Hermes Other

# add to Claude Code

claude mcp add lukasschwarz-elster-mcp-server -- npx -y elster-mcp-server

# add to Codex CLI

codex mcp add lukasschwarz-elster-mcp-server -- npx -y elster-mcp-server

// opencode.json

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

# add to OpenClaw

openclaw mcp add lukasschwarz-elster-mcp-server --command npx --arg -y --arg elster-mcp-server

# ~/.hermes/config.yaml

mcp_servers:
  lukasschwarz-elster-mcp-server:
    command: "npx"
    args: ["-y", "elster-mcp-server"]

// mcp.json

{
  "mcpServers": {
    "lukasschwarz-elster-mcp-server": {
      "command": "npx",
      "args": [
        "-y",
        "elster-mcp-server"
      ]
    }
  }
}

Changelog

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.

2 Aug 26 +34
- CVE-2025-66414 affects this package: high ▼ security
- Provenance: unverified → fail ▼ security
- Known CVEs: unverified → fail ▼ security
- Install scripts: unverified → pass ▲ security
- Malware scan: unverified → pass ▲ security
- Stability: Stability not yet verified: not enough scan history yet (needs a 30-day window). security
- MCP protocol: unverified → fail ▼ functional
- Tool coverage: 100 → unverified ▼ functional
- License: unverified → pass ▲ functional
- Dependency health: unverified → partial ▲ functional
- Maintenance: unverified → pass ▲ functional
- Schema quality: unverified → good ▲ functional
- First check of Schema quality: unverified functional
- Licence: MIT functional
31 Jul 26 −24
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
27 Jul 26 43

First indexed and scored.

Show 2 earlier entries Hide earlier entries

Diagnostics

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 3 Aug 2026 · Analysed npm/[email protected]

Provenance none

Ecosystem: npm · Outcome: none

Vulnerabilities 1 finding

ID	CVE	Severity	Vector	Fix available
GHSA-w48q-cv73-mx4w	CVE-2025-66414	high		yes

Dependencies 115 packages

115 packages in the resolved dependency tree · 113 deprecated · 35 stale.

The dependency tree was only partially resolved, so these counts may be incomplete.

MCP tools — 14 exposed · ~1,020 tokens

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.

Tool Tokens

elster_config_show ~36

Shows the currently loaded ELSTER configuration (with secrets redacted) so you can verify env vars / config.json were picked up.

Input Output Examples

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

elster_est_start ~119

Starts an ESt 1 A (Einkommensteuererklärung) form-prep session. Opens the form, fills taxpayer basics from config + any extra fields you provide (by ELSTER input id/name hint), runs Prüfung, then waits 30 min for you to review in the portal. NEVER submits.

Input Output Examples

Name	Type	Req	Description
data	object	—	Optional map of field-id hints → values. Each key is matched against ELSTER input id/name as substring. Use empty {} to only fill taxpayer basics from config.
year	integer	yes	—

No output schema declared.

No examples provided.

elster_eur_start ~168

Starts an EÜR (Anlage Einnahmen-Überschuss-Rechnung) form-prep session. Fills the form up to Prüfung, then tries to "Speichern und Verlassen" so the draft survives in ELSTER. NEVER submits.

Input Output Examples

Name	Type	Req	Description
data	object	yes	Map of field names to numeric amounts. Supported fields: betriebseinnahmen, kfzPrivatNutzung, fahrzeugkosten, kfzSteuer, telekommunikation, versicherungen, bewirtung, reisekosten, bankgebuehren, frem…
year	integer	yes	—

No output schema declared.

No examples provided.

elster_kennziffern_list ~55

Returns the list of supported UStVA Kennziffern (codes 81, 86, 66 etc.) with descriptions and whether they are NET (base amount) or TAX (tax amount).

Input Output Examples

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

elster_login_test ~42

Verifies that the configured certificate + password can log into the ELSTER portal. Returns success and final URL or an error. Use this once before submitting anything.

Input Output Examples

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

elster_session_cancel ~35

Cancels a running session (closes the browser, marks status as CANCELLED).

Input Output Examples

Name	Type	Req	Description
sessionId	string	yes	—

No output schema declared.

No examples provided.

elster_session_list ~30

Lists all currently tracked sessions (USTVA / EUR / EST / SYNC) with their status.

Input Output Examples

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

elster_session_status ~53

Returns the current status, progress log, and any screenshot path for a session started via elster_ustva_start / elster_eur_start / elster_est_start.

Input Output Examples

Name	Type	Req	Description
sessionId	string	yes	—

No output schema declared.

No examples provided.

elster_sync_history ~48

Reads "Übermittelte Formulare" (transmission history) from ELSTER. Optionally downloads PDFs.

Input Output Examples

Name	Type	Req	Description
downloadPdfs	boolean	—	—
years	array	—	—

No output schema declared.

No examples provided.

elster_sync_inbox ~46

Reads ELSTER inbox messages ("Posteingang"). Optionally downloads each message as PDF.

Input Output Examples

Name	Type	Req	Description
downloadPdfs	boolean	—	—
maxPages	integer	—	—

No output schema declared.

No examples provided.

elster_ustva_confirm ~55

Confirms submission of a UStVA session that is in AWAITING_CONFIRM state. Triggers the final "Absenden" click. Returns the transmission ticket on success.

Input Output Examples

Name	Type	Req	Description
sessionId	string	yes	—

No output schema declared.

No examples provided.

elster_ustva_detect_reverse_charge ~69

Tests whether a voucher would be detected as Reverse-Charge (§13b UStG) based on the configured supplier patterns. Returns matched supplier and region (EU / NON_EU), or null.

Input Output Examples

Name	Type	Req	Description
contactName	string	—	—
description	string	—	—

No output schema declared.

No examples provided.

elster_ustva_generate_xml ~135

Generates an ELSTER UStVA XML snapshot for archiving. Does NOT submit (submission goes via elster_ustva_start). Useful for audit trails.

Input Output Examples

Name	Type	Req	Description
period	integer\|string	yes	Month (1-12) or quarter as "Q1".."Q4"
report	object	yes	Map of Kennziffer → amount in EUR. Keys are the bare 2-3 digit code (e.g. "81", "66"). Net amounts for NET-type codes, tax amounts for TAX-type codes.
year	integer	yes	Tax year, e.g. 2026

No output schema declared.

No examples provided.

elster_ustva_start ~129

Starts a UStVA submission session. Opens a browser, logs in, fills the form, runs Prüfung, then PAUSES at AWAITING_CONFIRM. You must explicitly call elster_ustva_confirm to send. Returns a sessionId — poll status via elster_session_status.

Input Output Examples

Name	Type	Req	Description
period	integer\|string	yes	Month (1-12) or "Q1".."Q4"
report	object	yes	Map of Kennziffer → amount in EUR (bare digit keys, e.g. "81":12345.67).
year	integer	yes	—

No output schema declared.

No examples provided.

On this page

Handy links

Scoring key

80+ high trust
60–79 medium
below 60 low

How we score

Score history · last 30 days

27 Jul 3 Aug