Skip to main content
Glama
dinggi5

Kura

Kura (蔵 — die Schatzkammer, die Schätze bewahrt)

Lokale EVM-Wallet für KI-Agenten. Eine Wallet, bei der ein Mensch per Passwort genehmigt, wenn ein KI-Agent wie Claude auf dem Mac Internetzahlungen (x402) durchführt.

  • Keine Wallet für Menschen (wie MetaMask etc.), sondern für KI-Agenten

  • Keine Cloud-SaaS — läuft nur lokal. Die Schlüssel verlassen diesen Computer nicht.

  • KI fordert die Zahlung an → Mensch genehmigt per Passwort → Ausführung

  • Die Chain ist Base (Ethereum L2, Gebühren fast 0). Standard ist das Testnetz (Base Sepolia)


Auf einen Blick

[ AI 앱 (Claude Code / 데스크톱) ]
        │  MCP로 "결제해줘" 요청
        ▼
[ Kura 데스크톱 앱 ]  ← 승인 팝업 → 사람이 비밀번호 입력
        │  서명 (키는 이 앱 안에서만)
        ▼
[ Base 체인 / x402 페이실리테이터 ]  ← 실제 결제

Das Passwort wird nur im Eingabefeld der Kura-App abgefragt. Es gelangt weder in den Chat noch in MCP- oder Konfigurationsdateien.


Related MCP server: cardzero-mcp

Installation

Apple-Silicon-Mac (macOS 11 oder höher)

(A) Homebrew

brew install --cask dinggi5/tap/kura

(B) DMG direkt herunterladen

Lade unter Releases Kura_<Version>_aarch64.dmg herunter, öffne es und ziehe Kura in den Ordner Programme.

Da es eine App ist, der man seine Schlüssel anvertraut, habe ich in SECURITY.md sogar die Befehle aufgeschrieben, wie man prüft, ob die heruntergeladene App wirklich von mir stammt.

(C) Aus dem Quellcode bauen

Voraussetzungen: Rust, Node.js (20.19+ oder 22.12+ — Vite-7-Anforderung), macOS.

git clone https://github.com/dinggi5/kura.git
cd kura
git checkout v0.1.1   # 배포본과 같은 소스. 빼면 개발 중인 최신 코드가 받아져요
npm ci                # package-lock.json 그대로 설치 (install 은 버전이 올라갈 수 있어요)

# 개발 모드로 바로 실행
npm run tauri dev

# 앱으로 빌드해 /Applications에 설치
npm run tauri build -- --bundles app --no-sign
ditto src-tauri/target/release/bundle/macos/Kura.app /Applications/Kura.app
open /Applications/Kura.app

Updates

Die App aktualisiert sich selbst.
Unter Einstellungen → Info kannst du Version und Änderungen einsehen und auf Jetzt installieren und neu starten klicken.

  • Nur die Prüfung ist automatisch — die Installation musst du immer selbst anstoßen.

  • Heruntergeladene Dateien werden nur installiert, nachdem die Signatur geprüft wurde (Signaturprüfung kann nicht deaktiviert werden). Details stehen im Abschnitt „Updates" in SECURITY.md.

  • Wenn du die automatische Update-Prüfung nicht möchtest, deaktiviere Einstellungen → Info → Beim Start prüfen.

Deinstallation

⚠️ Wenn du die App löschst, wird die Wallet nicht gelöscht. Schlüssel, Einstellungen und Transaktionsverlauf liegen im Ordner ~/.jigap außerhalb der App. Wenn du nur die App löschst, bleiben sie erhalten — das habe ich absichtlich so gemacht, damit du nicht versehentlich Vermögenswerte verlierst (auch brew uninstall --zap löscht sie nicht).

# 앱만 제거 (지갑은 남음 — 나중에 다시 설치하면 그대로 이어서 써요)
brew uninstall --cask dinggi5/tap/kura   # 또는 /Applications/Kura.app 을 휴지통으로

Um auf diesem Mac auch die Wallet vollständig zu löschen, halte dich unbedingt an diese Reihenfolge:

  1. Stelle zuerst sicher, dass du die 12-Wörter-Wiederherstellungsphrase in der Hand hast. Du kannst sie über die Schlüssel-Schaltfläche im App-Header erneut ansehen.

  2. Wenn noch ein Guthaben vorhanden ist, transferiere es in eine andere Wallet.

  3. Beende Kura vollständig (Menüleisten-Symbol rechtsklicken → Beenden). Wenn die App läuft, schreibt sie alle paar Sekunden Statusdateien in ~/.jigap, sodass der gelöschte Ordner sofort wieder neu entsteht.

  4. Beende auch KI-Tools (wie Claude Code), an die Kura MCP angebunden ist.

  5. Wenn du den Autostart aktiviert hast, deaktiviere ihn oder führe rm ~/Library/LaunchAgents/Kura.plist aus (diese Datei bleibt erhalten, wenn du die App in den Papierkorb legst. Bei brew uninstall --cask wird sie mit entfernt).

  6. Führe dann rm -rf ~/.jigap aus.

Wenn du das letzte rm -rf ~/.jigap ohne die 12 Wörter ausführst, kann niemand mehr die Vermögenswerte dieser Wallet wiederherstellen.


Erster Start

Kura lebt in der Menüleiste. Beim Start erscheint in der Menüleiste oben auf dem Bildschirm ein Schatzkammer-Symbol (◻︎), und das Fenster klappt nur nach unten auf, wenn du auf dieses Symbol klickst. Wenn du woanders hinklickst, schließt es sich, und die App bleibt im Hintergrund und wartet weiter auf KI-Zahlungsanfragen. Zum vollständigen Beenden: Symbol rechtsklicken → Beenden. (Beim ersten Start ohne Wallet öffnet sich das Fenster automatisch.)

  1. Wallet erstellen — Lege ein Passwort (mindestens 8 Zeichen) fest, das du bei jeder Überweisung eingibst. Mit diesem Passwort wird der Schlüssel verschlüsselt gespeichert (~/.jigap/wallet.enc).

  2. Seed-Backup — Es werden 12 Wörter angezeigt. Das ist der echte Eigentumsnachweis für deine Vermögenswerte. Schreibe sie auf Papier oder in einen Passwort-Manager. Selbst wenn du das Passwort vergisst, kannst du mit den 12 Wörtern alles wiederherstellen: Beende die App, stelle zuerst sicher, dass du die 12 Wörter in der Hand hast, lösche dann ~/.jigap/wallet.enc und starte die App neu. Über Importieren auf dem ersten Bildschirm kannst du sie wiederherstellen (auch in einer anderen Standard-BIP-39-Wallet möglich). Aber: Wenn du diese Datei ohne die 12 Wörter löschst, verlierst du deine Vermögenswerte für immer.

  3. Willkommenstour — Sie erklärt Aufladen, KI-Verbindung und Sicherheitsvorkehrungen. Du kannst sie jederzeit über ⓘ Hilfe im Header erneut ansehen.


Guthaben aufladen (USDC)

Für Zahlungen benötigt deine Wallet USDC (digitaler Dollar).

  • Tippe in der App auf Empfangen, um Adresse und QR-Code zu sehen.

  • Wenn du von einer Börse oder einer anderen Wallet sendest, wähle unbedingt das Base-Netzwerk. Sendest du über ein anderes Netzwerk, verlierst du dein Geld.

  • Im Testnetz (Standard) ist es kein echtes Geld. Übe mit den kostenlosen Test-Coins über die Faucet-Schaltfläche auf dem Empfangsbildschirm.

  • ETH ist optional — Bei x402-Zahlungen übernimmt der Facilitator die Gebühren, sodass ETH auch 0 sein kann. Nur wenn du über Senden in der App direkt überweist, brauchst du etwas ETH für Gas (Base-Gebühren liegen bei etwa 1 Cent). Es reicht, nur USDC aufzuladen.


KI (Claude) verbinden

Registriere den Kura-Server in den MCP-Einstellungen der KI-App, um sie zu verbinden. Nach der Verbindung erscheint auf dem Hauptbildschirm das Abzeichen „Claude verbunden". Ab Version 0.1.2 ist der MCP-Server in der App enthalten, sodass du ohne Quellcode-Klon oder Rust-Installation verbinden kannst.

Der einfachste Weg — der Bildschirm „KI verbinden" in der App

Tippe auf das Abzeichen „KI nicht verbunden" oben auf dem Hauptbildschirm, um den Verbindungsbildschirm zu öffnen.

  • Claude Desktop — Tippe auf die Schaltfläche „Verbinden", und es erscheint ein Fenster zur Erweiterungsinstallation in Claude. Tippe einfach auf „Installieren", fertig.

  • Claude Code — Wird mit einem einzigen Tastendruck registriert (die App führt claude mcp add für dich aus). Ab dem nächsten claude-Start ist es in jedem Ordner verbunden.

Unten siehst du, wie du dasselbe manuell machst.

Claude Desktop — eine einzige Erweiterungsdatei

Lade kura-<Version>.mcpb von der Release-Seite herunter und doppelklicke darauf. Claude Desktop fragt dann nach der Installation. (Oder: Claude-Einstellungen → Erweiterungen → Datei auswählen.)

Die Erweiterung enthält keine ausführbare Datei — nur einen Launcher, der den signierten und notariell beglaubigten MCP-Server in der installierten Kura.app nach Signaturprüfung ausführt. Deshalb musst du zuerst die Kura-App installieren.

Claude Code · Andere MCP-Apps

Registriere das Binärprogramm in der App mit absolutem Pfad:

claude mcp add --scope user kura -- /Applications/Kura.app/Contents/MacOS/kura-mcp

(--scope user bedeutet nicht „nur dieser Ordner", sondern dass es überall verwendet werden kann. Wenn du es nur in einem Projekt nutzen willst, kannst du es weglassen.)

Bei anderen MCP-Apps trägst du Folgendes in die Einstellungen ein:

{
  "mcpServers": {
    "kura": {
      "command": "/Applications/Kura.app/Contents/MacOS/kura-mcp"
    }
  }
}

Wenn du aus dem Quellcode entwickelst

Die Datei .mcp.json im Repository-Root ist bereits vorhanden. Wenn du in diesem Ordner claude ausführst, wird sie automatisch erkannt (beim ersten Mal fragt sie, ob du den Server verwenden willst — genehmige es). Dieser Pfad ist für die Entwicklung gedacht und wird bei jedem cargo run neu gebaut — wenn du die installierte Version nutzt, ist die obige App-Pfad-Registrierung richtig.

Werkzeuge, die die KI nutzen kann: get_wallet_status · get_balances · get_history (nur lesen) · request_payment (Zahlungsanfrage → Genehmigungs-Popup in der App) · x402_fetch (Aufruf von URLs mit 402-Zahlung).

Wenn du die MCP-Werkzeuge änderst, musst du die KI-App neu starten, damit es wirksam wird (der Server wird beim Sitzungsstart einmal geladen).


So läuft eine Zahlung ab

  1. Die KI fordert eine Zahlung an.

  2. Das Kura-Fenster erscheint und zeigt, wie viel an wen gesendet wird (auch wenn das Fenster versteckt ist, erscheint es automatisch).

  3. Du gibst das Passwort ein und genehmigst.

  4. Die Zahlung wird ausgeführt und das Ergebnis an die KI zurückgegeben. Wenn du nicht innerhalb von 5 Minuten genehmigst, wird automatisch abgelehnt.


Sicherheitsmodell

  • Passwort-Genehmigung — Standardmäßig ist bei jeder Zahlung eine Passwort-Genehmigung erforderlich (wenn du automatische Zahlungen aktivierst, nur unter den folgenden Bedingungen als Ausnahme). Der Schlüssel wird verschlüsselt (Argon2id + AES-256-GCM) gespeichert und nur für die Zahlung entschlüsselt und sofort wieder gelöscht (bei aktivierter automatischer Zahlungssitzung wird er nur während der Entsperrung im Speicher gehalten).

  • Limits — Du legst in den Einstellungen fest, wie viel pro Transaktion / pro Tag gesendet werden darf (Standard: 5 pro Transaktion, 20 USDC pro Tag). Bei Überschreitung wird blockiert.

  • Notfall-Sperre — Wenn du die Schild-Schaltfläche im Header aktivierst, werden alle Überweisungen sofort blockiert.

  • Vertrauenswürdige Adressen · Automatische Zahlungen — Für die automatische Genehmigung ohne Passwort müssen Sitzungs-Entsperrung + kleines Limit + vertrauenswürdige Adresse alle drei zutreffen. Sonst ist immer ein Passwort erforderlich.

  • Transaktionsverlauf — Alle gesendeten Überweisungen, blockierten Versuche und Signaturen werden protokolliert.

  • Lokal zuerst — Die Schlüssel (~/.jigap/) liegen außerhalb des Repos und werden nicht in git hochgeladen.

  • Keine Analyse- oder Font-CDN — Die App verbindet sich nur mit dreierlei selbst: ①RPC-Server für Guthabenabfrage und Überweisungen ②x402-Adressen, die die KI anfordert ③Update-Prüfung (GitHub). Nutzungsdaten werden nirgendwohin gesendet, und die Schriftarten sind in der App enthalten, sodass der Bildschirm auch offline vollständig angezeigt wird.

  • Update-Prüfung kann deaktiviert werden — Beim Start fragt die App bei GitHub nach einer neuen Version (dort bleiben deine IP-Adresse und die aktuelle Version gespeichert). Unter Einstellungen → Info → Beim Start prüfen kannst du diese Kommunikation deaktivieren. Ob die Prüfung ein- oder ausgeschaltet ist — die Installation musst du immer selbst anstoßen. Es kann sich nichts heimlich ändern.


Für Entwickler

Dieselbe Wallet kann auch über die CLI kura bedient werden (teilt sich MCP-Server und Kernlogik). Sie ist bereits in der installierten App enthalten. Füge eine Zeile zum PATH hinzu und schon kannst du sie nutzen:

sudo mkdir -p /usr/local/bin
sudo ln -sf /Applications/Kura.app/Contents/MacOS/kura-cli /usr/local/bin/kura
kura status

Um sie aus dem Quellcode auszuführen:

cargo run --manifest-path ./kura-mcp/Cargo.toml --bin kura -- status
cargo run --manifest-path ./kura-mcp/Cargo.toml --bin kura -- balance
cargo run --manifest-path ./kura-mcp/Cargo.toml --bin kura -- history --limit 10
cargo run --manifest-path ./kura-mcp/Cargo.toml --bin kura -- pay <주소> <금액> --token usdc
cargo run --manifest-path ./kura-mcp/Cargo.toml --bin kura -- fetch <URL>

pay/fetch akzeptieren kein Passwort über die CLI — die Kura-App muss laufen, und ein Mensch muss das Passwort im Genehmigungs-Popup eingeben.

Tests:

(cd src-tauri && cargo test)        # 백엔드(지갑·암호화·한도·송금)
(cd kura-mcp && cargo test)         # MCP/CLI 어댑터
npx tsc --noEmit && npx vite build  # 프론트

Die Prozedur zur Erstellung einer Distribution (signierte, notariell beglaubigte DMG) findest du in docs/RELEASE.md. Du benötigst ein Apple-Developer-Konto und eine einmalige Einrichtung. Danach ist es nur noch eine Zeile:

./scripts/release.sh

Technologie-Stack

Desktop

Tauri (Rust + Web-Frontend)

Frontend

React + Tailwind CSS, Framer Motion, Lucide, Pretendard

Chain

Base / alloy-rs

Zahlung

x402 (EIP-3009 Off-Chain-Signatur)

KI-Verbindung

MCP-Server (rmcp)

Struktur: [Rust-Kern(src-tauri)] ← MCP / CLI-Adapter(kura-mcp). Nur der GUI-Prozess hat Schlüsselzugriff (Signierung) — das ist die letzte Verteidigungslinie.


Lizenz · Status

MIT-Lizenz — Da es sich um Code handelt, der mit Schlüsseln und Geld umgeht, sollte man ihn direkt lesen, prüfen und umschreiben können.

Wenn du eine Schwachstelle entdeckst, melde sie bitte über den privaten Weg in SECURITY.md, bevor du ein Issue erstellst. In derselben Datei steht auch, was Kura nicht verhindern kann.

Die enthaltene Schriftart Pretendard steht unter der SIL Open Font License 1.1 (Volltext).

Die erste Priorität bin ich selbst — eine Wallet für koreanische Entwickler und Kreative, die auf dem Apple-Silicon-Mac mit lokalen LLMs/Claude bezahlen. Es ist noch eine frühe 0.1.x-Version. Ich empfehle, zuerst im standardmäßigen Testnetz zu üben und im Mainnet nur so viel einzuzahlen, wie du dir leisten kannst zu verlieren.

Available Tools

7 tools
get_balancesBalancesA
Read-only

Reads the active account's USDC (for payments) and gas-token balances on the active network (Base mainnet, Arc mainnet, Base Sepolia, or Arc testnet, per the user's setting). The eth field is the gas balance and is ABSENT on chains where gas is paid in USDC itself (Arc) — there the USDC balance already covers gas, so never add the two together. Errors if there is no wallet.

NameRequiredDescriptionDefault

No parameters

TDQS

A4.1/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered; the description goes further by disclosing the no-wallet error case and a critical cross-field caveat (the `eth` gas field is absent on Arc and must never be added to the USDC balance). It does not cover rate limits or refresh/freshness behavior, so it stops short of a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, front-loaded with the core read action, followed by the field caveat and the error case. The parenthetical enumeration of the four networks is slightly heavy but genuinely useful since it defines the valid scope; nearly every sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no parameters and no output schema, the description carries the burden of explaining the return shape, and it does so reasonably: it names the two balance types, flags the missing `eth` field per chain, and states the error case. Minor gap is freshness/caching and what happens across multiple networks at once.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so the baseline is 4. The description's field-level discussion (USDC vs `eth` gas balance and their relationship on Arc) concerns returned values rather than inputs, but it does add interpretive value that the empty schema cannot.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('Reads') and resource (USDC and gas-token balances) for the active account, and pins the scope to the active network with named chains. An agent can immediately distinguish this from get_wallet_status or get_history without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by the purpose but never stated as when-to-use or when-not-to-use, and no sibling tool is named as an alternative. The only routing signal is the failure condition ('Errors if there is no wallet'), which is a precondition rather than guidance on choosing this tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

get_historyHistoryA
Read-only

Returns the active account's recent transaction attempts, newest first. status is one of sent, blocked, failed, signed (x402 signed, awaiting settlement), settled (x402 settled, settle_tx is the settlement tx), settle_failed, unknown (a signed transaction was submitted but the wallet couldn't confirm the chain received it — detail is its tx hash; it may have gone through, so never resend on the strength of this entry alone; the wallet app later rechecks it on-chain and turns it into sent or reverted), reverted (mined but reverted on-chain — no money moved, only gas), expired (an x402 signature that was never used before it expired — no money moved), or received (money that came in — to is the sender, detail the tx hash; both are empty for ETH a contract sent; found on-chain by the wallet app while it runs, back to 90 days). Use limit to cap how many come back (default 20).

NameRequiredDescriptionDefault
limitNoHow many recent entries to return (default 20, max 200).

TDQS

A4.2/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare readOnlyHint and openWorldHint; the description carries substantial extra behavior: per-status meaning, which statuses mean no money moved (reverted, expired), that 'unknown' may have gone through and the wallet rechecks it on-chain, that 'received' comes from an app-driven on-chain scan back to 90 days. This is exactly the context annotations cannot supply.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The core purpose is front-loaded and every clause carries information — the status enumeration is necessary because there is no output schema. It loses a point because the status glossary is delivered as one very dense run-on sentence rather than a scannable list.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema and only one optional parameter, the description fully covers what the agent needs: return ordering, default limit, and the complete semantics of every status value including financial and safety implications. Nothing material is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% for the single 'limit' parameter, so the schema already documents default 20 and max 200; the description only restates the default. Baseline 3 applies since the schema does the heavy lifting and the description adds no new parameter syntax.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource — 'Returns the active account's recent transaction attempts, newest first' — including scope (active account) and ordering. The resource is unmistakably distinct from siblings like get_balances and get_wallet_status, so an agent can route without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by the resource and by the embedded warning 'never resend on the strength of this entry alone', which quietly steers the agent away from acting on 'unknown' entries via x402_resubmit. However, it never explicitly says when to call this versus alternatives, nor states prerequisites or exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

get_wallet_statusWallet statusA
Read-only

Returns the wallet's state and address. state is encrypted (normal), legacy, or none. address is the ACTIVE account's address; accounts lists every account in the wallet (index, address, label) and account is the active index. Balances, history, and payment requests all use the active account, and only the user can switch accounts, in the wallet app. No password needed — read only.

NameRequiredDescriptionDefault

No parameters

TDQS

A4.4/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=false, and the description goes well beyond them: it enumerates the state values (encrypted/legacy/none), clarifies that address is the ACTIVE account while accounts lists all accounts, and discloses that only the user can switch accounts in the wallet app. It also reassures no password is needed, which is actionable auth context.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core purpose, then structured field-by-field. Every sentence carries information, though the trailing 'No password needed — read only' partially restates the readOnlyHint annotation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With zero parameters, no output schema, and annotations covering safety, the description supplies exactly the missing pieces: what fields come back, what the state values mean, and how the active-account concept relates to sibling tools. Nothing an agent needs to call this correctly is absent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so the baseline is 4. The description additionally documents the shape of the returned object (index, address, label, active index), which is useful given no output schema exists, though these are return values rather than input semantics.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Returns the wallet's state and address') and enumerates the exact fields returned (state, address, accounts, account). The sibling set (get_balances, get_history, request_payment) is clearly distinct, and the description anchors its scope to the active account rather than those other resources.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied rather than stated: it explains that balances, history, and payment requests all key off the active account, which tells the agent why it might call this first, but it never explicitly says when to use this tool versus get_balances/get_history, nor names an alternative.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

lookup_agentLook up an agent (ERC-8004)A
Read-only

Reads an agent's ERC-8004 record from the registry on the active network (read-only, on-chain only — the wallet never fetches the agent's website). Give it agent_id, the agent's number in the Identity Registry. Returns: registered, owner, wallet (the registered agentWallet), token_uri and the uri_domain read from it, declared_name (what the record calls itself), and feedback_clients (how many addresses left feedback). Pass pay_to and/or resource to also get a comparison: whether the address equals the registered wallet and whether the resource's domain equals the domain listed on-chain. IMPORTANT: registration is permissionless — anyone can register any name, domain, or wallet, and anyone can leave feedback. Being registered is NOT proof of safety. Only a mismatch is a strong signal, and only when the agent number came from a source you trust (the service's own docs), not from the payment response itself.

NameRequiredDescriptionDefault
pay_toNoOptional: an address to compare against the agent's registered wallet.
agent_idYesThe agent's ERC-8004 number (agentId — the Identity Registry NFT token id).
resourceNoOptional: a resource URL whose domain is compared with the domain listed on-chain.

TDQS

A4.6/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint and openWorldHint, and the description goes well beyond them: it discloses that nothing is fetched off-chain, that registration is permissionless, and that being registered is not evidence of safety. This is exactly the kind of adversarial-context caveat an agent needs before treating the result as a trust signal.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads the core action, then the return fields, then the comparison behavior, then the safety caveat. The enumerated return list is long but every item earns its place given there is no output schema. Slightly dense, but no filler sentences.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description fully enumerates the returned fields (registered, owner, wallet, token_uri, uri_domain, declared_name, feedback_clients) plus the conditional comparison outputs. For a read-only lookup with three parameters, nothing an agent needs to call or interpret it is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so baseline is 3, but the description adds real semantics: agent_id is the number in the Identity Registry, and pay_to/resource exist specifically to produce address and domain comparisons. That comparison behavior is not derivable from the terse schema property descriptions alone.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: reads an agent's ERC-8004 record from the on-chain registry on the active network. It immediately scopes what the tool does not reach ("the wallet never fetches the agent's website"), which separates it cleanly from the payment/wallet siblings. An agent can tell what this returns without opening the schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives concrete invocation guidance (supply agent_id; optionally pass pay_to and/or resource to trigger a comparison) and states the condition under which the result is trustworthy (mismatch only matters when the agent number came from a source you trust). No sibling alternative is named, but the siblings are unrelated domains so the omission is minor. Clear context without explicit when-not-to-call routing.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

request_paymentRequest a paymentA
Destructive

Asks the user to make a payment. The wallet app opens an approval window, and the payment is only sent once the user approves it with their password (it waits up to 5 minutes). The one exception is autopay, which the user turns on themselves — only then can a payment be approved automatically, and only within an unlocked session, a small limit, and a trusted address. Arguments: to (recipient address), amount (decimal string), token (USDC by default, or ETH), memo (what the payment is for — the user reads it to decide, so always fill it in), and optionally agent_id (the recipient's ERC-8004 number, if a service told you one — the wallet then shows the user whether the address matches that agent's registered wallet). Per-payment and daily limits and the emergency lock are enforced by the app. Never send a password as an argument — the user types it in the app. Returns: status, tx_hash, detail, and an explorer link. status is approved (the chain accepted the transfer), rejected or failed (nothing was sent — safe to ask again), or unknown: the user approved but the wallet couldn't confirm whether the transfer reached the chain (tx_hash is set when known). unknown means it MAY have been sent — never ask again on your own; tell the user and have them check the history or the tx.

NameRequiredDescriptionDefault
toYesRecipient address (42 characters, starting with 0x).
memoNoWhat the payment is for — the user reads this in the approval window, so fill it in.
tokenNoToken: "USDC" (default) or "ETH".
amountYesAmount as a decimal string, for example "1.5".
agent_idNoOptional: the recipient's ERC-8004 agent number, if you know it from the service's own documentation or agent card. The wallet reads that agent's on-chain record and tells the user whether the address you are paying is the one registered for that agent. A mismatch is the useful part — a match is not proof of anything, since anyone can register. Leave it out if you don't know it; a wrong number just produces a "no such agent" note.

TDQS

A4.8/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare destructiveHint=true and idempotentHint=false, but the description adds far more: a 5-minute approval timeout, password-entry-only-in-app, app-enforced per-payment/daily limits and emergency lock, autopay preconditions (unlocked session, small limit, trusted address), and the semantics of approved/rejected/failed/unknown including the no-retry rule on unknown. That is exactly the behavioral disclosure a payment tool needs.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose, then arguments, then return semantics in a logical order. It is long, but the length is justified by the absence of an output schema and the high stakes of an irreversible transfer; each section earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description fully documents the return contract (status, tx_hash, detail, explorer link) and the three status branches, plus the critical unknown-may-have-been-sent caveat. Nothing needed to invoke or handle the result is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds operative meaning beyond the schema: 'USDC by default', the instruction to always fill in memo because the user reads it, and a caution that agent_id mismatch is the useful signal while a match proves nothing. It largely restates the schema fields, but the added rationale has real value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('Asks the user to make a payment') and immediately distinguishes it from read-only siblings like get_balances/get_history by describing the approval-window flow. An agent can tell this is the mutating spend path without opening the schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit when-to-use and when-not-to-act guidance: the approval window is the normal path, autopay is the only auto-approval exception and only under user-enabled conditions, and on 'unknown' the agent must never retry on its own but hand off to the user. This is actionable routing logic, not vague context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

x402_fetchFetch a paid URL (x402)A
Destructive

Calls an x402 paid API or URL. It sends the request first — GET by default, or the given method (POST, PUT, PATCH, DELETE) with optional headers and a JSON object body; if the server answers 402 Payment Required, it asks the user to approve the required payment (exact scheme, the active network, that chain's USDC) in the wallet app, then sends the SAME request (same method, headers and body) again with the payment header and returns the content. If no payment is required (no 402), it just returns the response. Redirects are not followed once a payment header is attached (nor at all when method, headers or body are given) — a redirect comes back as an error with the new address. Text and JSON come back in body. Binary responses (images, PDF, audio) are saved to a file whose path is in saved_file (with content_type); a PNG/JPEG/GIF/WebP image up to 3 MB is also attached as an image. Text longer than 100,000 characters is cut in body and kept whole in saved_file. If saving takes too long (macOS asking for Downloads access), the result comes back first and saving_file names where the file will appear. Settlement takes one of two shapes, chosen by the server's requirement: a facilitator settles the signed EIP-3009 authorization (no gas from this wallet), or — where gas is paid in USDC itself and the server asks for eip3009-client-broadcast — the wallet broadcasts the transfer itself, so the price AND its gas leave this balance. Approval works exactly as in request_payment (password by default; automatic only when the user has turned autopay on), and the app enforces per-payment and daily limits and the emergency lock. Never send a password as an argument. Arguments: url (required), method, headers, body (JSON object), memo (what the payment is for — the user reads it to decide), agent_id. Returns: payment, paid, status, http_status, body, and amount/pay_to/settlement when paid; on a chain where the wallet broadcasts the payment itself, tx and explorer point at that transaction (both are empty on the facilitator-settled path, where settlement_tx/settlement_explorer carry the transaction the seller reports in its receipt — the seller's word, not checked on-chain by the wallet). IMPORTANT — decide on payment, which says where the money is: "none" = nothing was paid, trying again is safe (declined, no 402, or "reverted": the chain rejected the transfer and only gas was spent); "confirmed" = the money left the wallet; "unknown" = it MAY have left (status pending/unknown, or settlement_failed on the facilitator path, where the server's refusal doesn't prove the facilitator didn't settle). For confirmed and unknown without content, asking again can pay a second time — stop and tell the user, showing the tx (when a tx came back without content, x402_resubmit re-sends its proof without paying again). paid is kept for older callers and is simply payment != "none". Read notice when present, and never retry on an HTTP status alone: after the money moved the server may answer with a fresh 402 challenge that reads as if the payment never happened.

NameRequiredDescriptionDefault
urlYesURL of the paid resource to fetch (http/https).
bodyNoJSON object sent as the request body (not allowed with GET). Content-Type defaults to application/json. The paid retry sends exactly the same body.
memoNoWhat the payment is for — the user reads this in the approval window, so fill it in.
methodNoHTTP method: GET (default), POST, PUT, PATCH or DELETE. Many paid APIs (search, image generation) take POST with a JSON body. The paid retry uses the same method.
headersNoExtra request headers as a JSON object of name → value. Payment headers, Host, Content-Length and connection headers are set by the wallet and are refused here. The paid retry sends the same headers.
agent_idNoOptional: the seller's ERC-8004 agent number, if you know it from the service's own documentation or agent card. The wallet then reads that agent's on-chain record and shows the user whether the payment address and the resource domain match what is registered. Leave it out if you don't know it — a wrong number just produces a "no such agent" note.

TDQS

A4.6/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only say destructive/openWorld/non-idempotent, while the description discloses far more: the retry-safety semantics of the `payment` field ('none'/'confirmed'/'unknown'), the double-payment hazard, facilitator vs eip3009-client-broadcast gas behavior, redirect handling under a payment header, the 100k truncation and saved_file behavior, and the warning never to retry on HTTP status alone. This is exactly the value-beyond-annotations the dimension rewards, and the destructiveHint is consistent with money leaving the wallet.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The basic request flow is front-loaded before the settlement and retry-safety detail, and nearly every sentence carries operational or safety weight. It is nevertheless very long for a single tool, with some density that could be tightened, so it stops short of a 5.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, so the description carries the full burden of explaining returns — and it does: payment/paid/status/http_status/body/amount/pay_to/settlement, tx/explorer vs settlement_tx, and notice. For a 6-param destructive payment tool, an agent has everything needed to call it and interpret the result safely.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds real meaning: it explains memo is what the user reads to decide, agent_id drives an on-chain ERC-8004 verification note, and it warns never to pass a password as an argument. These are semantic additions beyond the schema text.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The opening sentence gives a specific verb and resource ('Calls an x402 paid API or URL') and the whole description keeps the scope tight around paid HTTP fetching. It distinguishes itself from request_payment by reference ('Approval works exactly as in request_payment') and from x402_resubmit by naming it as the no-pay-again path. An agent can separate it from every sibling without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It clearly states the triggering condition (server answers 402 → user approval → same request resent), when the tool is a plain fetch (no 402), and routes to x402_resubmit when a tx came back without content. It does not give an explicit 'prefer X over request_payment when...' decision rule, but the surrounding context is strong enough to infer usage.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

x402_resubmitResubmit an x402 payment proofA
Idempotent

Resubmits the on-chain proof of an x402 payment this wallet already broadcast itself, to get the content it paid for. Use it when x402_fetch returned a tx without content (status pending, unknown or undelivered, or settlement_failed with a tx). No new money moves and no approval is asked: the wallet re-sends the same proof (the tx plus the saved challenge values) to the same URL. It first checks the tx on-chain — if it isn't mined yet you get status pending (wait and call again), if it reverted you get reverted (payment none: nothing was paid, so paying again is a new decision). Sellers keep proofs acceptable only for a while (the reference server: 10 minutes), so a late resubmit can be refused — that is settlement_failed with a notice; do not pay again then, tell the user and show the tx. Proofs are kept for 7 days. Returns the same shape as x402_fetch.

NameRequiredDescriptionDefault
txYesThe `tx` that x402_fetch returned for a payment the wallet broadcast itself (status pending, unknown or undelivered, or settlement_failed with a tx).

TDQS

A4.9/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Far exceeds the annotations: it states no new money moves and no approval is requested, describes the on-chain pre-check and each resulting status (pending, reverted with payment none), and discloses the seller acceptance window (~10 minutes on the reference server) and 7-day proof retention. The idempotent/read-only nature is confirmed in prose rather than left to the hints alone.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Purpose is front-loaded in the first clause, followed by the usage trigger and then the behavioral detail. The length is justified by the number of distinct outcomes (pending, reverted, refused) that the agent must handle correctly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Although there is no output schema, the description states the return shape matches x402_fetch and enumerates every status the caller may encounter along with the correct reaction to each. Nothing an agent needs to invoke or interpret this tool is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds real meaning: the tx must be one the wallet broadcast itself and is re-sent together with the saved challenge values to the same URL. That provenance and pairing context goes beyond the schema's bare field description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource (resubmits the on-chain proof of an x402 payment this wallet already broadcast) plus the goal (to get the content it paid for). It also distinguishes itself from the sibling x402_fetch by explicitly framing itself as the follow-up for a tx that came back without content.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly names the trigger condition: 'Use it when x402_fetch returned a `tx` without content (status pending, unknown or undelivered, or settlement_failed with a tx).' It also names the alternative (x402_fetch) and warns against paying again in the settlement_failed/refused cases.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Tool Schema Changelog

Recent tool additions, removals, and schema changes observed during successful MCP inspections.

  1. 1 tool updatev0.5.0
    • Changedx402_fetch3 fields changed
      • addedInput schema / properties / body
        Added value: +{
        +  "additionalProperties": true,
        +  "description": "JSON object sent as the request body (not allowed with GET). Content-Type defaults to\napplication/json. The paid retry sends exactly the same body.",
        +  "type": "object"
        +}
      • addedInput schema / properties / headers
        Added value: +{
        +  "additionalProperties": {
        +    "type": "string"
        +  },
        +  "description": "Extra request headers as a JSON object of name → value. Payment headers, Host,\nContent-Length and connection headers are set by the wallet and are refused here.\nThe paid retry sends the same headers.",
        +  "type": "object"
        +}
      • addedInput schema / properties / method
        Added value: +{
        +  "description": "HTTP method: GET (default), POST, PUT, PATCH or DELETE. Many paid APIs (search, image\ngeneration) take POST with a JSON body. The paid retry uses the same method.",
        +  "type": "string"
        +}
  2. 1 tool updatev0.4.3
    • Addedx402_resubmit
  3. 4 tool updatesv0.4.1
    • Changedget_history2 fields changed
      • removedInput schema / properties / limit / default
        Removed value: -null
      • removedInput schema / properties / limit / nullable
        Removed value: -true
    • Changedlookup_agent4 fields changed
      • removedInput schema / properties / pay_to / default
        Removed value: -null
      • removedInput schema / properties / pay_to / nullable
        Removed value: -true
      • removedInput schema / properties / resource / default
        Removed value: -null
      • removedInput schema / properties / resource / nullable
        Removed value: -true
    • Changedrequest_payment6 fields changed
      • removedInput schema / properties / agent_id / default
        Removed value: -null
      • removedInput schema / properties / agent_id / nullable
        Removed value: -true
      • removedInput schema / properties / memo / default
        Removed value: -null
      • removedInput schema / properties / memo / nullable
        Removed value: -true
      • removedInput schema / properties / token / default
        Removed value: -null
      • removedInput schema / properties / token / nullable
        Removed value: -true
    • Changedx402_fetch4 fields changed
      • removedInput schema / properties / agent_id / default
        Removed value: -null
      • removedInput schema / properties / agent_id / nullable
        Removed value: -true
      • removedInput schema / properties / memo / default
        Removed value: -null
      • removedInput schema / properties / memo / nullable
        Removed value: -true
  4. 1 tool updatev0.4.0
    • Changedrequest_payment1 field changed
      • addedInput schema / properties / agent_id
        Added value: +{
        +  "default": null,
        +  "description": "Optional: the recipient's ERC-8004 agent number, if you know it from the service's own\ndocumentation or agent card. The wallet reads that agent's on-chain record and tells the\nuser whether the address you are paying is the one registered for that agent. A mismatch\nis the useful part — a match is not proof of anything, since anyone can register.\nLeave it out if you don't know it; a wrong number just produces a \"no such agent\" note.",
        +  "format": "uint64",
        +  "minimum": 0,
        +  "nullable": true,
        +  "type": "integer"
        +}
  5. 2 tool updatesv0.3.0
    • Addedlookup_agent
    • Changedx402_fetch1 field changed
      • addedInput schema / properties / agent_id
        Added value: +{
        +  "default": null,
        +  "description": "Optional: the seller's ERC-8004 agent number, if you know it from the service's own\ndocumentation or agent card. The wallet then reads that agent's on-chain record and shows\nthe user whether the payment address and the resource domain match what is registered.\nLeave it out if you don't know it — a wrong number just produces a \"no such agent\" note.",
        +  "format": "uint64",
        +  "minimum": 0,
        +  "nullable": true,
        +  "type": "integer"
        +}
  6. 5 tool updatesv0.2.0
    • First observedget_balances
    • First observedget_history
    • First observedget_wallet_status
    • First observedrequest_payment
    • First observedx402_fetch

TDQS

A4.3/5.0

Scored across 7 tools

Disambiguation4/5

Most tools are clearly distinct (request_payment, get_wallet_status, get_balances, get_history, lookup_agent). The only partial overlaps are request_payment vs x402_fetch (both trigger payments) and x402_fetch vs x402_resubmit, though the descriptions clearly delineate direct transfer vs paid API call vs proof resubmission without new money.

Naming Consistency4/5

Consistent snake_case verb_noun pattern (request_payment, get_wallet_status, get_balances, get_history, lookup_agent), with x402_fetch and x402_resubmit using a coherent namespace prefix. Minor deviation from pure verb_noun but overall predictable.

Tool Count5/5

7 tools is well-scoped for a wallet/payment server, with each tool earning its place. No redundant or filler tools.

Completeness4/5

Covers the core wallet lifecycle: payments, status/accounts, balances, history, x402 paid fetches with resubmission, and agent registry lookup. Minor gaps like account-switching (explicitly user-only) or explicit cancellation are reasonable omissions, but no major workflow dead ends.

Maintenance

ActivityActive
ResponsivenessUnresponsive

Related MCP Connectors

Related MCP Servers

  • A
    license
    A
    quality
    D
    maintenance
    Gives AI agents a smart-contract wallet on Base (USDC) with 10 stdio tools: create wallets, send USDC payments, pay x402-protected HTTP resources, and run ERC-8183 escrow Jobs for A2A service delivery.
    10
    9 npm
    MIT
  • A
    license
    A
    quality
    A
    maintenance
    A budget-bound x402 payment wallet for AI agents: it autonomously pays HTTP 402 payment-gated URLs across every major chain (EVM, Solana, and many non-EVM families). Self-custodial and backendless, your key, your RPC, with spend caps enforced before any on-chain send.
    8
    9
    MIT