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dinggi5

Kura

Kura (蔵 — el cofre que guarda tesoros)

Billetera EVM local para agentes de IA. Una billetera en la que una persona aprueba con contraseña cuando una IA como Claude realiza pagos por internet (x402) en Mac.

  • No es una billetera para personas (como MetaMask), sino para agentes de IA

  • No es un SaaS en la nube — solo funciona localmente. Las claves nunca salen de este ordenador.

  • La IA solicita el pago → la persona aprueba con contraseña → se ejecuta

  • La cadena es Base (L2 de Ethereum, comisiones casi nulas). Por defecto, testnet (Base Sepolia)


De un vistazo

[ 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

La contraseña solo se introduce en el campo de la app de Kura. Nunca aparece en el chat, en MCP ni en archivos de configuración.


Related MCP server: cardzero-mcp

Instalación

Mac con Apple Silicon (macOS 11 o superior)

(A) Homebrew

brew install --cask dinggi5/tap/kura

(B) Descarga directa del DMG

Descarga Kura_<versión>_aarch64.dmg desde Releases, ábrelo y arrastra Kura a la carpeta Applications.

Como es una app a la que confías tus llaves, en SECURITY.md he dejado incluso los comandos para verificar que la app descargada es realmente la que yo he creado.

(C) Compilar desde el código fuente

Requisitos previos: Rust, Node.js (20.19+ o 22.12+ — requiere Vite 7), 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

Actualización

La app se actualiza sola.
En Configuración → Información consulta la versión y los cambios, y pulsa Instalar ahora y reiniciar.

  • Solo la comprobación es automática; la instalación siempre requiere que pulses tú.

  • El archivo descargado solo se instala tras verificar su firma (la verificación de firma no se puede desactivar). Los detalles están en la sección «Actualización» de SECURITY.md.

  • Si no quieres que la app compruebe actualizaciones automáticamente, desactiva Configuración → Información → Comprobar al iniciar.

Desinstalación

⚠️ Desinstalar la app no elimina la billetera. Las claves, la configuración y el historial de transacciones están en la carpeta ~/.jigap, fuera de la app, así que si solo eliminas la app, todo permanece — lo hice a propósito para que no pierdas tus activos por accidente (ni siquiera brew uninstall --zap lo borra).

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

Para eliminar también la billetera de este Mac, sigue este orden estrictamente:

  1. Comprueba primero que tienes la frase de recuperación de 12 palabras. Puedes volver a verla con el botón de llave del encabezado de la app.

  2. Si queda saldo, transfiérelo a otra billetera.

  3. Cierra Kura por completo (clic derecho en el icono de la barra de menús → Salir). Si está abierta, escribe un archivo de estado en ~/.jigap cada pocos segundos, así que la carpeta que borres volverá a aparecer de inmediato.

  4. Cierra también las herramientas de IA conectadas al MCP de Kura (como Claude Code).

  5. Si tienes activado el inicio automático, desactívalo o ejecuta rm ~/Library/LaunchAgents/Kura.plist (si eliminas la app a la papelera, este archivo permanece; con brew uninstall --cask se elimina junto con la app).

  6. Después, rm -rf ~/.jigap

Si ejecutas el último rm -rf ~/.jigap sin las 12 palabras, nadie podrá recuperar jamás los activos de esa billetera.


Primer uso

Kura vive en la barra de menús. Al ejecutarla, aparece un icono de cofre (◻︎) en la barra de menús superior, y la ventana se despliega hacia abajo solo al pulsar ese icono. Al hacer clic en cualquier otro lugar se cierra, y la app permanece en segundo plano esperando solicitudes de pago de la IA. Para apagarla por completo: clic derecho en el icono → Salir. (En el primer arranque, cuando aún no hay billetera, la ventana se abre sola.)

  1. Crear billetera — Elige una contraseña (8 caracteres o más) que tendrás que introducir en cada transferencia. Con esta contraseña se cifran y guardan las claves (~/.jigap/wallet.enc).

  2. Copia de seguridad de la semilla — Aparecen 12 palabras. Son la prueba real de propiedad de tus activos, así que anótalas en papel o en un gestor de contraseñas. Aunque olvides la contraseña, con las 12 palabras puedes recuperarlo todo: cierra la app, comprueba primero que tienes las 12 palabras, borra ~/.jigap/wallet.enc y vuelve a abrir la app; se restaurará con Importar de la primera pantalla (también puedes importarlas en cualquier otra billetera estándar BIP-39). Pero si borras ese archivo sin las 12 palabras, perderás los activos para siempre.

  3. Tour de bienvenida — Te explica cómo recargar, conectar la IA y las medidas de seguridad. Puedes volver a verlo cuando quieras desde ⓘ Ayuda del encabezado.


Recargar fondos (USDC)

Para pagar, la billetera necesita USDC (dólares digitales).

  • Pulsa Recibir en la app y verás la dirección y un código QR.

  • Al enviar desde un exchange u otra billetera, elige siempre la red Base. Si lo envías a otra red, perderás los fondos.

  • En la testnet (por defecto) no es dinero real. Usa el botón Faucet de la pantalla Recibir para obtener monedas de prueba gratis y practicar.

  • ETH es opcional — En los pagos x402, el facilitador paga las comisiones, así que puedes tener 0 ETH. Solo necesitas un poco de ETH para el gas cuando envías directamente con Enviar de la app (las comisiones de Base rondan 1 céntimo). Con recargar solo USDC es suficiente.


Conectar la IA (Claude)

Se conecta registrando el servidor de Kura en la configuración MCP de la app de IA. Al conectarse, aparece la insignia «Claude conectado» en la pantalla principal. Desde la versión 0.1.2, el servidor MCP está integrado en la app, así que puedes conectarte sin clonar el código fuente ni instalar Rust.

La vía más fácil: la pantalla «Conexión de IA» de la app

Pulsa la insignia «IA no conectada» en la parte superior de la pantalla principal y se abrirá la pantalla de conexión.

  • Claude Desktop — Al pulsar el botón «Conectar», aparece la ventana de instalación de la extensión en Claude. Basta con pulsar «Instalar».

  • Claude Code — Se registra con un solo botón (la app ejecuta claude mcp add por ti). Desde la siguiente ejecución de claude, estará conectado en cualquier carpeta.

A continuación, cómo hacer lo mismo manualmente.

Claude Desktop: con un solo archivo de extensión

Descarga kura-<versión>.mcpb desde la página de releases y haz doble clic; Claude Desktop te preguntará si quieres instalarlo. (O en Configuración de Claude → Extensiones → Seleccionar archivo.)

La extensión no contiene ejecutables — solo un lanzador que, tras verificar la firma, ejecuta el servidor MCP firmado y notarizado que está dentro de Kura.app. Por eso primero debes instalar la app de Kura.

Claude Code · otras apps MCP

Registra el binario de la app con su ruta absoluta:

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

(--scope user es una opción para que esté disponible en cualquier lugar, no solo «en esta carpeta». Si solo lo vas a usar en un proyecto, puedes omitirla.)

En otras apps MCP, escribe esto en la configuración:

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

Si estás desarrollando desde el código fuente

El .mcp.json de la raíz del repositorio ya está incluido. Si ejecutas claude en esta carpeta, se detectará automáticamente (la primera vez te preguntará si quieres usar el servidor; pulsa Aprobar). Esta ruta es para desarrollo, ya que recompila con cargo run cada vez — si vas a usar la versión instalada, registra la ruta de la app como se indica arriba.

Herramientas que la IA puede usar: get_wallet_status · get_balances · get_history (solo lectura) · request_payment (solicitud de pago → ventana de aprobación en la app) · x402_fetch (llamada a URLs con pago 402).

Si cambias las herramientas MCP, reinicia la app de IA para que se apliquen (el servidor se carga una vez al iniciar la sesión).


Así fluye un pago

  1. La IA solicita un pago.

  2. Se abre la ventana de Kura mostrando cuánto y a dónde se envía (se abre automáticamente aunque la ventana esté oculta).

  3. Introduce la contraseña y aprueba.

  4. El pago se ejecuta y el resultado vuelve a la IA. Si no apruebas en 5 minutos, se rechaza automáticamente.


Modelo de seguridad

  • Aprobación con contraseña — Por defecto, cada pago requiere aprobación con contraseña (si activas el pago autónomo, solo hay excepciones bajo las condiciones siguientes). Las claves se guardan cifradas (Argon2id + AES-256-GCM) y solo se descifran al pagar, borrándolas de inmediato (con la sesión de pago autónomo activada, se conservan en memoria solo mientras dura el desbloqueo).

  • Límites — Configura cuánto se puede enviar por operación y por día (por defecto: 5 por operación · 20 USDC diarios). Si se supera, se bloquea.

  • Bloqueo de emergencia — Al activar el botón de escudo del encabezado, todas las transferencias se bloquean al instante.

  • Direcciones de confianza · pago autónomo — Para aprobar automáticamente sin contraseña deben cumplirse las tres condiciones: sesión desbloqueada + límite pequeño + dirección de confianza. En cualquier otro caso, siempre se pide contraseña.

  • Historial de transacciones — Registra todas las transferencias enviadas, los intentos bloqueados y las firmas.

  • Prioridad local — Las claves (~/.jigap/) están fuera del repositorio y no se suben a git.

  • Sin analíticas ni CDN de fuentes — La app solo se conecta a internet por tres motivos: ①el servidor RPC para consultar saldos y enviar transferencias, ②la dirección x402 que solicita la IA, ③la comprobación de actualizaciones (GitHub). No se envía ningún registro de uso a ningún sitio, y las fuentes están incluidas en la app, así que la interfaz funciona igual en modo offline.

  • La comprobación de actualizaciones se puede desactivar — Al abrir la app, consulta a GitHub si hay una versión nueva (allí quedan registrados tu IP y la versión actual). Si la desactivas en Configuración → Información → Comprobar al iniciar, esa comunicación también desaparece. Tanto si la dejas activada como si no, la instalación siempre requiere que pulses tú — nada se cambia en secreto.


Para desarrolladores

También puedes manejar la misma billetera con la CLI kura (comparte el servidor MCP y la lógica central). Ya viene incluida en la app instalada; basta con añadir una línea al PATH:

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

Para ejecutarla desde el código fuente:

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 no aceptan la contraseña por CLI — la app de Kura debe estar abierta y la persona introduce la contraseña en la ventana de aprobación.

Pruebas:

(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

El procedimiento para crear la distribución (DMG firmado y notarizado) está en docs/RELEASE.md. Requiere una cuenta de Apple Developer y una configuración inicial; a partir de ahí, es una sola línea:

./scripts/release.sh

Stack tecnológico

Escritorio

Tauri (Rust + frontend web)

Frontend

React + Tailwind CSS, Framer Motion, Lucide, Pretendard

Cadena

Base / alloy-rs

Pagos

x402 (firma off-chain EIP-3009)

Conexión IA

Servidor MCP (rmcp)

Estructura: [núcleo Rust (src-tauri)] ← adaptador MCP / CLI (kura-mcp). Solo el proceso de la GUI accede a las claves (firma) — esa es la última línea de defensa.


Licencia · estado

Licencia MIT — Es código que maneja llaves y dinero, así que creo que debe poder leerse, verificarse y modificarse directamente.

Si encuentras una vulnerabilidad, avísame por la vía privada indicada en SECURITY.md antes de abrir un issue. En ese mismo documento también he anotado lo que Kura no puede impedir.

La fuente Pretendard incluida está bajo la SIL Open Font License 1.1 (texto completo).

El primer usuario soy yo mismo — es una billetera para desarrolladores y creadores coreanos que pagan con LLM locales o Claude en Mac con Apple Silicon. Aún es una versión inicial 0.1.x, así que te recomiendo que primero la pruebes en la testnet (la opción por defecto) y que en la mainnet solo pongas lo que puedas permitirte perder.

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

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