Arxo MCP server

Which servers in the official MCP registry are Arxo's own, whether they answer, and what they offer. A program checked each of these, nobody copied them from a product page.

read 2026-10-20

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Whose server it is

Registry nameio.arxo/charterverified in the MCP registry

The registry name sits under arxo.io. The registry only lets a publisher use that namespace after proving control of the domain through DNS or HTTP.

When we asked itchecked 2026-10-20

Stateanswerschecked 2026-10-20
Tools20
Server calls itselflaw-dsl-charter
Server version0.1.0
Protocol version2025-06-18

On 2026-10-20 the server answered initialize and tools/list without a sign-in. First answer in 489 ms.

Should an agent connect itNot proven either way yet

Whether its tools do the product's job has not been judged yet.
Checked on 2 of the 7 days it takes to judge reliability.

Once connected

law_publish_answer change data without a sign-in: anyone with the address can call them.
Parameters are untyped or undescribed in 8 of 20 tools: check arguments before calling.

Said by rules from the measurements above. The likely first call is a model's pick from the tool list; read its description before relying on it.

Measured dailydaily checks: 2, the first on 2026-10-20

INITE MCP scoreafter a weeka score needs 7 daily checks: 2 so far
Use176 npm downloads a week
Answeredmeasuring2 of the 7 daily checks it takes to print a share
Median first answer1316 ms
Space in an agent's context≈ 8,562 tokensthe definitions of all its tools (20), which an agent carries on every turn
Tool definitionsA · 93 of 100
Typed results7 of 20 toolsdeclared outputSchema: results come typed, read once

Parameters without a type: in 1 of 20
Parameters without a description: in 8 of 20

What an agent can do with it

not sure · check a draft act's duties, deadlines and references for consistency
not sure · calculate passenger compensation from a pinned regulation edition
can do · connect an AI agent to answer rule questions with cited grounds

Each of the product's use cases, put to Jev against this server's tool list: can an agent do it with these tools?

Worth a look

Tools that change data, on a server that answers without a sign-in: law_publish_answer

A program checks the server once a day: initialize and tools/list, no model. Tokens are the definitions' length at about four characters a token. The grade averages six checks of every tool's name, description, schema and annotations; it says how well the tools are described, not whether they work. The score weighs what was measured and nothing else: answering (30%), doing the product's job (25%), definitions (20%), context (10%) and use (15%). A part that was not measured is left out, and a hidden instruction caps the score at 40. The state of vendors' MCP servers: method and numbers →

Tools it offers20 tools · read 2026-10-20

law_search
A semantic SEARCH over formalised law: a question or a notion in your own words → candidates with addresses — predicates with signatures, rules, article fragments. This is the layer of DISCOVERY, not of the answer: the result says WHAT to…
law_passport
Passport of an exact release: purpose, interface, boundaries, checks and performance. The reports section holds the history of measurements, failures included. Entries are paged by JSON Pointer; next continues the answer.
law_answer_capabilities
A machine-readable matrix of the Lens producers that are actually installed, of replay/projection checks, profiles, limits and the contract tests that confirm them. declared_only means a schema with no executable witness.
law_capture_answer
Run a registered producer and obtain producerControl/0.2 for a later verifiable preparation of a Lens. The producer is chosen only from the shipped registry.
law_prepare_answer
At the explicit request of the user, repeat between 1 and 12 earlier law_ask or law_process_run calls (the course of a case, DECISION-0160), compare their replayControl strictly, and prepare a non-public frozen document for 24 hours. The…
law_publish_answer
Publish a prepared document. Repeating it with the same preparationId idempotently returns the same URL and the same separate revocation secret.
law_revoke_answer
Revoke a published document using its separate secret. The public id alone grants no control; revocation closes the HTML page, the API and the download.
law_packages
The catalogue of formalised law: instruments, predicates with signatures, the boundaries of coverage. This is where the NAMES of predicates come from — they must never be guessed. But do NOT start from the catalogue when looking for the…
law_ask
Put a question to formalised law. When the answer is "not established" it carries whyNot — the engine's why_not report §185: the candidate rules and the state of every conjunct (satisfied / not satisfied / undetermined); the missing facts…
law_screen
Build a necessary condition — a superset — for the preliminary selection of rows from an external source (DECISION-0120). This is NOT a legal answer and NOT SQL: the result is a typed tree and a manifest of the extensions up to TRUE…
law_rules
The rules of formalised law put into words: exactly how a predicate is derived (premises, source articles). Call this BEFORE supplying facts to law_ask — the rules say which facts are needed instead of leaving them to be guessed. For…
law_explain
Unfold the proof of a law_ask answer into a chain "rule ← premises → conclusion". The compact input: question (the original law_ask arguments, truth/collect), resultHash and codeHash from the provenance of the answer. The server repeats…
law_case_ask
The ask operation §168.4 (DECISION-0165, DECISION-0399): run a registered case of a case package over its pinned dependencies and return the canonical evaluation document with a proof and a manifest. The question is JSON per…
law_sources
Sources: by default short excerpts (view=summary), 5 texts per page, with the address of the full text in fragments[].full. Either package or fragment is required (a StableId from law_search/law_rules). view=full returns exact parts of…
law_argue
How robust a conclusion is: the map of the dispute under the argumentation profile §274 (DECISION-0039). The answer falls into four classes: SKEPTICALLY_ACCEPTED — the conclusion is invulnerable (it survives in the grounded extension)…
law_process
Which stages the procedure established by an instrument consists of, and whether it carries a structural defect (O-5, DECISION-0052). The stages, the transitions and the condition of every transition are reconstructed from the…
law_process_run
How a particular case will run, step by step (O-5, DECISION-0052): a log of {date, attempt?, facts?} is executed frame by frame, and the law of each frame is the law of ITS date. The answer says: which stages have been entered; which…
law_editions
The axis of editions (O-2): what changed in an instrument between two dates of the law — the state of the editions, the dating of the norms and the semantic diff §215 between the D1 projections. The verdict NOT_DATED means "there was…
law_query
A deterministic LawQL query over the CLIR of a formalization: a question about the model of the act itself, not about a case. Relations: nodes(id,kind,package,package_name,path), edges(from,to,role), anchors(node,anchor,act,locator,path)…
law_report
A REPORT of a divergence between the formalisation and the source: the answer contradicts the pinned text, a norm of the source is not expressed by a rule, a §218 label diverges from the text, an address cannot be found. A report is a…

How to connect

Add the server to your MCP client config. Claude Desktop, Cursor and most other clients read this shape:

{
  "mcpServers": {
    "charter": {
      "type": "http",
      "url": "https://mcp.arxo.io/mcp/charter"
    }
  }
}

Add it

Claude Code, in a terminal

claude mcp add --transport http arxo https://mcp.arxo.io/mcp/charter

Add to Cursor Add to VS Code

claude.ai, ChatGPT and other clients: add https://mcp.arxo.io/mcp/charter as a custom connector in the settings.

Also shipped through: npm

Other servers listed as Arxo's

io.arxo/cnafanswers, 16 toolsverified in the MCP registry
io.arxo/code-civilanswers, 20 toolsverified in the MCP registry
io.arxo/de-bgbnot asked yetverified in the MCP registry
io.arxo/fide-chessnot asked yetverified in the MCP registry
io.arxo/piccnot asked yetverified in the MCP registry

Each line is something a program found when it went looking: the registry entry, the server's own answer, a spec that parses. A missing line means we did not find it, not that it does not exist.