io.github.lukasschwarz/elster-mcp-server
NPM · ELSTER-MCP-SERVER · SCANNED SEP 25
Drive the German tax portal ELSTER via Puppeteer: submit UStVA, prepare EUER/ESt, sync inbox.
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 Security80
- 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
- 37 of 116 dependencies flagged as unhealthy (1 deprecated). 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 89 days ago).Pass
- Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability79
- AI-judged instruction clarity (excellent).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 Management83
- Stability observed for 25 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
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
Tool Safety75
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- 0 of 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "elster_ustva_detect_reverse_charge" implies "charge" and declares no destructiveHint at all, which the MCP spec reads as destructive by default. See how to fix → Fail
- An AI judge read all 14 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities20
- Spec-recency check failed: implements MCP spec 2024-11-05; the latest is 2026-07-28. See how to fix → Fail
How do I install the io.github.lukasschwarz/elster-mcp-server server?
io.github.lukasschwarz/elster-mcp-server runs locally as an npm package, launched with npx -y elster-mcp-server. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · elster-mcp-server
claude mcp add lukasschwarz-elster-mcp-server -- npx -y elster-mcp-server
{
"mcpServers": {
"lukasschwarz-elster-mcp-server": {
"command": "npx",
"args": [
"-y",
"elster-mcp-server"
]
}
}
} {
"servers": {
"lukasschwarz-elster-mcp-server": {
"command": "npx",
"args": [
"-y",
"elster-mcp-server"
]
}
}
} codex mcp add lukasschwarz-elster-mcp-server -- npx -y elster-mcp-server
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"lukasschwarz-elster-mcp-server": {
"type": "local",
"command": [
"npx",
"-y",
"elster-mcp-server"
],
"enabled": true
}
}
} openclaw mcp add lukasschwarz-elster-mcp-server --command npx --arg -y --arg elster-mcp-server
mcp_servers:
lukasschwarz-elster-mcp-server:
command: "npx"
args: ["-y", "elster-mcp-server"] {
"McpServers": {
"lukasschwarz-elster-mcp-server": {
"Transport": "stdio",
"Command": "npx",
"Arguments": [
"-y",
"elster-mcp-server"
]
}
}
} assistant mcp add lukasschwarz-elster-mcp-server -t stdio -c npx -a -y elster-mcp-server
{
"mcpServers": {
"lukasschwarz-elster-mcp-server": {
"command": "npx",
"args": [
"-y",
"elster-mcp-server"
]
}
}
} 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 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 24 Sept 26 −3
- Stability: pass → 0.80 functional
- 23 Sept 26 +1
- Stability: 0.97 → pass security
- 21 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.
- 19 Sept 26 +1
- Security disclosure: unverified → fail ▼ functional
- 17 Sept 26 −3
- Security disclosure: fail → unverified ▼ functional
- Stability: pass → 0.80 functional
- 16 Sept 26 +1
- Stability: 0.97 → pass security
- 14 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.
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 25 Sept 2026 · Analysed npm/elster-mcp-server@0.1.0
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 →
Vulnerabilities 3 findings
| ID | CVE | Severity | Vector | Fix available |
|---|---|---|---|---|
| GHSA-w48q-cv73-mx4w | CVE-2025-66414 | high | yes | |
| GHSA-7pqw-9j4j-h8q3 | CVE-2026-19693 | high | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H | no |
| GHSA-jmr9-qjv8-65gv | CVE-2026-56876 | high | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N | no |
Background: What a vulnerability scan can and cannot prove →
Dependencies 116 packages
| Packages resolved | 116 |
|---|---|
| Deprecated | 1 |
| Stale | 36 |
| 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 →
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 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.
| 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.
| 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 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 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).
| 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 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.
| 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.
| 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.
| 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.
| 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.
| 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.
| 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.
| 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.
What is the io.github.lukasschwarz/elster-mcp-server server?
io.github.lukasschwarz/elster-mcp-server is listed in the public MCP registry as io.github.lukasschwarz/elster-mcp-server. Drive the German tax portal ELSTER via Puppeteer: submit UStVA, prepare EUER/ESt, sync inbox. This page covers its npm package (elster-mcp-server).
Is the io.github.lukasschwarz/elster-mcp-server server safe to use?
io.github.lukasschwarz/elster-mcp-server scores 70 out of 100 on VerifyMCP. We recorded 3 known advisories against it as of 25 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 io.github.lukasschwarz/elster-mcp-server server expose?
io.github.lukasschwarz/elster-mcp-server exposes 14 tools: elster_login_test, elster_config_show, elster_kennziffern_list, elster_ustva_generate_xml, elster_ustva_detect_reverse_charge, and 9 more. Their descriptions and schemas cost roughly 1,020 tokens of context every time the server is loaded.
Is the io.github.lukasschwarz/elster-mcp-server server still maintained?
io.github.lukasschwarz/elster-mcp-server is still listed as active in the MCP registry. We last reached this channel on 25 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 io.github.lukasschwarz/elster-mcp-server server under?
io.github.lukasschwarz/elster-mcp-server declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.