kvasir.legal

kvasir API

Read-only access to German, Austrian, Swiss and EU law. Resolve a citation, check a draft against the official wording, search, and walk the citation graph. Every object carries its source, its version and a pinpoint down to the sentence.

Base URL	https://kvasir.legal/api/v1
MCP	https://kvasir.legal/mcp · setup & tools
Auth	API key or OAuth. Six read endpoints also work without a key (20 calls a day per IP).
Format	JSON over HTTPS. No SDK needed.

Try it now, no key needed:

curl --get https://kvasir.legal/api/v1/resolve \
  --data-urlencode "cite=§ 573 Abs. 2 Nr. 2 BGB" -d include=none

import requests

r = requests.get("https://kvasir.legal/api/v1/resolve",
                 params={"cite": "§ 573 Abs. 2 Nr. 2 BGB", "include": "none"})
print(r.json()["exists"], r.json()["uri"])

const url = new URL("https://kvasir.legal/api/v1/resolve");
url.search = new URLSearchParams({ cite: "§ 573 Abs. 2 Nr. 2 BGB", include: "none" });
const obj = await (await fetch(url)).json();
console.log(obj.exists, obj.uri);

Authentication

Create an account, confirm your email and issue a key in the dashboard. Send it in either header:

X-API-Key: kvk_…
Authorization: Bearer kvk_…

Without a key, /resolve, /search, /object, /relations, /verify and /check-draft (up to 5,000 characters) answer in sandbox mode: 20 calls a day per IP, marked with X-Sandbox: true.

MCP clients sign in with OAuth instead of a key. Keys and OAuth count against the same plan.

Scopes

Scope	Allows
legal.read	Everything except draft checking. Always granted.
legal.check	/check-draft and check_draft, the only calls that receive a full document. Can be withheld per key or connection.
workspace	The user's own collections and notes (MCP, OAuth only). Opt-in at sign-in.

A key limited to legal.read gets 403 insufficient_scope on draft checking, so a connector can be provisioned that cannot receive client documents at all. More on Trust & security.

Limits & errors

60 requests per minute per key on Single, 600 on Team. Monthly volume counts in sips: 1 per lookup, 2 per search or relations page, 5 per check-draft, batches per item. Single includes 2,000 sips a month; Team allowances are agreed per contract. Usage is in your dashboard.

Status	Meaning
400	Bad parameter, e.g. an unknown jurisdiction code. The body lists the valid values.
401	Missing or invalid key.
403	Key lacks the scope (insufficient_scope).
429	Limit reached: rate_limited, quota_exceeded or sandbox_limit. Honour Retry-After.
503	Brief infrastructure hiccup. Retry.

Errors are JSON: { "error", "hint", "docs_url" }. Responses carry X-RateLimit-Limit, -Remaining and -Reset (keyless: X-Sandbox-Remaining). exists: false is not an error: the citation or URI matched nothing in the corpus.

Resolve a citation

GET /api/v1/resolve

Citation string in, canonical object out. Handles free text like Art. 6 Abs. 1 lit. f DSGVO, § 1295 ABGB, C-311/18, and returns the pinpoint unit plus did-you-mean suggestions when nothing matches.

Parameter	Description
cite required	The citation.
include	What to return, see include. Default content.
quellen	Restrict to jurisdictions, see Jurisdictions.
lang	de: German wording for EU acts, fetched live from EUR-Lex.

exists answers for the cited pinpoint: § 573 Abs. 6 BGB is false with norm_exists: true, unit_exists: false and a reason, because § 573 ends at paragraph 4.

How special citations resolve

Ranges: f. and ff.

Return a range. f. is exact and follows the statute's order (§ 311 f. BGB ends at § 311a). ff. is open: suggested_to is marked as an inference. If nothing follows at all, range.valid is false. Below a provision (§ 305 Abs. 1 ff.) the range is exact and comes back as unit_range.

Several provisions

§§ 433, 434 BGB, § 823 Abs. 1 i.V.m. § 1004 BGB: the first is the main object, the rest are in also_cited. Top-level exists is false if any is invented.

Same abbreviation in two jurisdictions

Art. 141 BV exists in Switzerland and Bavaria. The answer carries ambiguous with every candidate. Pass quellen to settle it.

Artikel and Paragraphen

In Art. 246a § 1 EGBGB the § is part of the address. Citing the wrong divider still resolves but adds a marker_note.

Variants and old versions

Var. 2 resolves to the paragraph with variant.addressable: false. a.F. returns version.confirmed: false: the corpus holds current law and says so.

EU acts in German

The EU corpus is English. lang=de returns the equally authentic German text; content.language always states which one you got.

Verify citations

POST /api/v1/verify

Checks up to 200 citations in one call. Per citation: verified or unresolved, canonical URI, source and pinpoint.

{ "citations": ["§ 242 BGB", "Art. 6 DSGVO"], "quellen": "bund,eu" }
// or: { "text": "…" } to extract the citations first

Check a draft

POST /api/v1/check-draft

One call over a full draft: verifies every citation, compares quoted wording with the official text, and flags repealed law and pending amendments. Returns summary.verdict (pass | warn | fail) and findings with severities. Deterministic, no language model involved, nothing stored.

curl https://kvasir.legal/api/v1/check-draft \
  -H "X-API-Key: kvk_…" -H "Content-Type: application/json" \
  -d '{"text": "Nach § 573 Abs. 2 Nr. 2 BGB …", "quellen": "bund"}'

r = requests.post("https://kvasir.legal/api/v1/check-draft",
                  headers={"X-API-Key": "kvk_…"},
                  json={"text": draft, "quellen": "bund"})
print(r.json()["summary"]["verdict"])

Search

GET /api/v1/search

Semantic and full-text search, ranked: [{uri, kind, title, snippet, score}].

Parameter	Description
q required	Question or keywords.
kinds	norm, decision, material (opt-in). Comma-separated.
quellen	Jurisdictions (alias jurisdiction).
limit, offset	Paging. limit default 20, max 50. Refine the query rather than paging deep.

If part of the search failed, the response has a degraded field. Treat those results as incomplete, not as absence.

Get an object

GET /api/v1/object/<uri>

One object by URI, with include and lang as on /resolve.

{
  "uri": "norm:bund:BGB:242",
  "kind": "norm",
  "exists": true,
  "identity":   { "title": "§ 242 BGB", "href": "/bgb/242" },
  "provenance": { "source": "gesetze-im-internet.de", "version": "<hash>" },
  "content":    { "plain_text": "Der Schuldner ist verpflichtet …" },
  "units": [ { "path": "a1", "citation": "§ 242 Abs. 1 BGB", "text": "…" } ]
}

Get many objects

POST /api/v1/objects

Up to 100 URIs in one call: { "uris": [ … ], "include": "content" }.

Citation graph

GET /api/v1/relations/<uri>

Everything that cites an object (or that it cites), paged and ordered by authority, leading decisions first.

Parameter	Description
direction	in (default): what cites this. out: what this cites.
edge_type	e.g. zitiert_norm. The response lists all types with counts.
limit, offset	Paging. Default 50, max 200. Stable order, no repeats.

Changes

GET /api/v1/changes

Delta sync: every object changed since since (ISO timestamp), as URIs with timestamps. kinds defaults to norm,decision, limit to 500. Continue with cursor from next_cursor. Rows can repeat at page boundaries, so keep upserts idempotent.

Corpus status

GET /api/v1/status

Public. Counts and freshness per jurisdiction: *_updated (last change) and *_checked (last check against the official source, even when nothing changed), plus check_cadence. For a currency gate watch checks.repeal. Human view: Status, Sources.

MCP server

The same corpus as the REST API, as tools for Claude, ChatGPT, Copilot and any other MCP client. One endpoint, streamable HTTP, OAuth or API key.

Endpoint	https://kvasir.legal/mcp
Try without account	https://kvasir.legal/mcp/demo · 10 tool calls a day per IP
Auth	OAuth sign-in, or header X-API-Key: kvk_…

Connect

Claude	Settings → Connectors → Add custom connector → paste the endpoint → sign in.
ChatGPT	Settings → Apps & Connectors → Advanced → Developer mode → Create → endpoint, OAuth. In Business and Enterprise an admin enables it.
Microsoft 365 Copilot	IT adds the endpoint once in Copilot Studio as a custom MCP action (key as X-API-Key). Then available tenant-wide.
Legora	Workspace admin adds the endpoint as a custom MCP server (OAuth or key).
Perplexity · Le Chat	Settings → Connectors → add MCP connector with the endpoint and X-API-Key.

Developer tools:

claude mcp add --transport http kvasir https://kvasir.legal/mcp \
  --header "X-API-Key: kvk_…"

// .cursor/mcp.json  ·  .vscode/mcp.json
{
  "mcpServers": {
    "kvasir": {
      "url": "https://kvasir.legal/mcp",
      "headers": { "X-API-Key": "kvk_…" }
    }
  }
}

// claude_desktop_config.json, via mcp-remote
{
  "mcpServers": {
    "kvasir": {
      "command": "npx",
      "args": ["-y", "mcp-remote", "https://kvasir.legal/mcp",
               "--header", "X-API-Key: kvk_…"]
    }
  }
}

Tools

Eight tools read the corpus. Six more work with the user's own collections and notes in the kvasir app; they need the workspace scope, which only an OAuth sign-in can grant.

Corpus

resolve_citation legal.read

Citation string → canonical provision with pinpoint, or explicit findings when the citation is wrong. The usual entry point. REST: /resolve.

cite required	§ 242 Abs. 1 BGB, Art. 6 DSGVO, C-311/18
include, quellen	As in the REST API

Data: the citation string, used for the lookup and discarded.

verify_citations legal.read

Up to 200 citations at once: verified, unresolved or unparsed, with the reason when a real provision is cited wrongly.

citations required	List of citation strings
quellen	Jurisdiction filter

Data: citation strings only, not stored.

check_draft legal.check

A full draft: every citation, every quoted passage against the official wording, repealed law and pending amendments, plus a verdict.

text required	The draft, no markup needed
quellen	Jurisdiction filter

Data: the only tool that receives a full document. Processed entirely on kvasir's own servers by pattern matching, database lookups and local string comparison. No language model, no third party, nothing written to disk. Behind its own scope so it can be withheld.

search_legal legal.read

Provisions, decisions and materials by topic. Reports degraded if part of the search failed.

query required	Question or topic
kinds, quellen, limit, offset	As in the REST API

Data: the query is sent to Mistral to compute an embedding. The only egress of user text in the whole tool set. The vector is cached 24 h under a hash of the query; the query itself is not stored.

get_legal_object · get_legal_objects legal.read

One object by URI, or up to 100 in one call, with wording, provenance, citation string and deeplink.

uri / uris required	norm:bund:BGB:242, dec:eu:62018CJ0311, gesetz:eu:GDPR
include, commentary_scope	As in the REST API

Data: URIs, not stored.

get_legal_relations legal.read

The citation graph from one object, paged by authority, e.g. every decision citing a provision.

uri required	Start object
direction, edge_type, limit, offset	As in the REST API

Data: a URI, not stored.

legal_uri_grammar legal.read

The URI scheme and jurisdiction codes, so URIs can be built instead of guessed. No parameters.

Collections and notes

list_collections · get_collection workspace

The user's folders and those shared with them; one folder's items, with include="content" also the texts of up to 50 items as working context.

collection	Name or id (get_collection)
include	content to add the texts

add_to_collection · remove_from_collection workspace

Adds or removes items by URI. Adding creates the folder if needed. Removing only takes the item out of the folder. Deleting folders stays in the app.

collection required	Name or id
uris required	Canonical URIs
create_if_missing	Default true (add only)

list_notes · add_note workspace

Searches the user's notes on provisions, including notes colleagues shared with their team, or attaches a new one to a passage. The quote must match the provision's current text verbatim, otherwise the note is rejected.

query, law, limit	Filters (list_notes)
uri, quote, body	Provision, exact passage, note (add_note)
share_with_team	Make the note visible to the user's team (Team accounts only)

Data: these six tools read the signed-in user's own collections and notes and those their team shared with the team; they write only the user's own. API keys and the demo endpoint have no access to them.

Data handling

Stored	Usage metering only: key, date, tool name, call count. Never queries, citations or drafts.
Third parties	One: search_legal sends the query to Mistral for an embedding.
Writes	Only the six workspace tools, and only in the user's own collections and notes. Nothing writes to the legal corpus.
Scopes	legal.read for retrieval, legal.check for check_draft, workspace for collections and notes.
Freshness	Statutes and case law are checked daily; per-source state on Sources.

Security review details: Trust & security.

Object URIs

Kind	Pattern	Example
Provision	norm:{quelle}:{kuerzel}:{id}	norm:bund:BGB:242, norm:eu:GDPR:art_6
Statute	gesetz:{quelle}:{kuerzel}	gesetz:bund:BGB
Decision	dec:{quelle}:{id}	dec:eu:62018CJ0311 (Schrems II)
Material	mat:{quelle}:{id}	mat:eu:52022PC0454
Section	section:{quelle}:{kuerzel}:{hash}	from a statute's children
Concept	concept:{scheme}:{slug}	concept:eu:protection-of-personal-data
Old version	normversion:{id}	from include=versions

Unsure about an id? Go through /resolve; it returns canonical_uri. Materials are EU proposals and Commission guidelines (typ: guideline, not binding law), German federal bills (typ: vorhaben) and BaFin acts.

Jurisdictions

quellen restricts every call that has to choose a provision: a query parameter on /search and /resolve, a body field on /verify and /check-draft, an argument on the MCP tools. It filters, it does not rank, and the response echoes it. Set it whenever you know the jurisdiction: it turns an ambiguous warning into an answer.

Code	Jurisdiction	Contains
bund	Germany, federal	Statutes, federal courts, Bundestag bills, BaFin acts
by	Bavaria	State law, Bavarian courts
nrw	North Rhine-Westphalia	State law, NRW courts
sn · bb · hb	Saxony · Brandenburg · Bremen	State law
at	Austria	Federal and Länder law (region, e.g. at-wien), OGH, VfGH, VwGH
ch	Switzerland	Federal law
eu	European Union	Regulations, directives, CJEU, legislative materials

include

Comma-separated on /resolve, /object and /objects.

Value	Returns
content	Full text, HTML and metadata. Default.
none	Identity, provenance and pinpoint only. The light "does it exist?" call.
units	Addressable sub-units down to the sentence (a1, a2.s1, a2.n3.h2) or Randnummer (r17), each with text, citation and deeplink.
children	On a statute: its table of contents.
relations	Citation graph samples with totals, and on statutes the legislative layer: founding proposal, pending amendments, delegated acts, guidelines.
versions	Earlier wordings as normversion: URIs.
authority	Authority score in the citation graph.
commentary	Author-attributed commentary anchored to the object.
all	All of the above.

Need more volume, coverage or an endpoint that does not exist yet? [email protected]