1password

1Password MCP Server

Give your AI assistant a locked door to 1Password — not a pile of passwords in the chat.

@takescake/1password-mcp is a community Model Context Protocol (MCP) server. It lets Claude, Cursor, VS Code Copilot, OpenAI Codex, Gemini, and other MCP clients manage vaults and credentials through a 1Password Service Account.

Built on the MCP TypeScript SDK v2 with protocol negotiation for 2026-07-28 (and legacy clients). Secrets stay in 1Password; agents prefer op:// references and op_run so plaintext never has to land in the model transcript.

Not an official 1Password product. Community-built, Apache 2.0 licensed.

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Who this is for

You are…	You get…
Not deeply technical	A one-time setup: create a service account, paste the token into your AI app’s MCP settings, then ask in plain English (“list my automation vault”, “rotate the staging DB password”).
An agent / LLM	Fifteen typed tools, four workflow prompts, three browsable resources, and clear rules: prefer op_run + op:// over revealing secrets.
A developer / SRE	Full item CRUD, secure notes, password generation, vault allow-lists, Keychain token loading on macOS, and CI-friendly env config.

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Why teams pick this server

• Security-first defaults — password_read returns metadata, and item_get hides secret-bearing fields (passwords, SSH keys, OTP seeds, card numbers), unless you opt in with reveal: true.
• op_run (the MCP equivalent of op run) — inject op://vault/item/field into a local command’s environment; resolved secrets are redacted from the returned stdout/stderr on a best-effort basis (including common encodings).
• Full vault toolkit — list, search, get, edit, create logins & notes, rotate passwords, archive, or delete.
• Guided prompts — password generation, credential rotation, vault audit, and secret-reference helpers.
• Browsable resources — vault and item catalogs over onepassword://… URIs (no secrets in resource payloads).
• Modern MCP — stdio transport, Zod 4 schemas, MCP 2026-07-28 negotiation with legacy client compatibility.

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What you get

Tools (15)

Grouped the way agents and humans actually use them.

Discover

Tool	What it does
vault_list	List vaults the service account can access (id, name, description, type), limited to the allow-list if one is set.
item_lookup	Search a vault by title substring; optional limit (max 200).
item_list	List every item in a vault (id, title, category, tags, updatedAt) — never secrets.

Read (safe by default)

Tool	What it does
item_get	Full item: title, category, tags, notes, fields. Secret-bearing values (passwords and other concealed fields, SSH private keys, OTP seeds, card numbers) stay hidden unless reveal: true; only known non-secret field types are shown. Notes are returned as-is. Accepts op://… or vaultId + itemId.
password_read	Read one field (default password) via op://… or ids. Metadata-only unless reveal: true. Prefer op_run to use a secret.
op_check_ref	Validate op://vault/item/field and return non-secret metadata only (vault, item, field). Never the value.

Create & update

Tool	What it does
password_create	Create a Login or Password item (username, URL, tags, notes). returnSecret defaults to false.
note_create	Create a Secure Note with optional tags and custom fields.
password_update	Rotate a password / concealed field (creates the field if missing).
item_edit	Update title, notes (empty string clears), tags, URL; upsert or remove fields. Unreferenced fields stay untouched.
password_generate	Cryptographically secure random password (length 8–128; symbols/numbers/uppercase toggles).
password_generate_memorable	Memorable passphrase from a ~500-word list (word count, separator, number/symbol suffixes).

Use secrets without revealing them

Tool	What it does
op_run	Run a local command (command or argv) with env vars. Values matching op://… are resolved into the child process only; resolved secrets are redacted from returned output (best effort — see Security & privacy). Output is capped at 5 MiB per stream, and a timeout kills the whole process tree. Optional cwd, shell, timeout_ms, stdin.

Soft-delete & destroy

Tool	What it does
item_archive	Move an item to the archive (hidden from normal views).
item_delete	Permanently delete an item — cannot be undone.

Prompts (4)

Prompt	When to use it
generate-secure-password	Generate (random or memorable) and optionally store — without dumping the password into chat.
credential-rotation	Find → verify access → generate → update → confirm op:// reference.
vault-audit	Inventory a vault by category; flag duplicates / oddities — never reveal secrets.
secret-reference-helper	Build a paste-ready op://vault/item/field from names.

Resources (3)

URI	Contents
onepassword://config	Non-secret server config (name, version, log level, token source, Node version).
onepassword://vaults	JSON list of accessible vaults (limited to the allow-list if one is set).
onepassword://vaults/{vaultId}/items	URI template (listed by resources/templates/list): JSON item metadata for one vault (no secret values).

Upgrading from 4.x: resource URIs used to start with 1password://, which MCP clients could never read (a URI scheme can't start with a digit). Replace any hard-coded 1password:// URIs with onepassword://.

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Before you start

You need two things:

1. Node.js 20 or newer
2. A 1Password Service Account with access to the vault(s) you want the AI to use

Create a service account (plain English)

1. Sign in to your 1Password account on the web.
2. Open Developer → Service Accounts (or follow 1Password’s guide).
3. Create a service account and grant it only the vaults you want automation to touch (for example an Automation or CI vault — not your personal banking vault).
4. Copy the token once. Treat it like a master key.

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Quick start

Claude Desktop / Cursor / VS Code / most IDEs

Add this to your MCP config (exact file depends on the app):

{
  "mcpServers": {
    "1password": {
      "command": "npx",
      "args": ["-y", "@takescake/1password-mcp"],
      "env": {
        "OP_SERVICE_ACCOUNT_TOKEN": "YOUR_SERVICE_ACCOUNT_TOKEN"
      }
    }
  }
}

Restart the app, then try: “List my 1Password vaults.”

macOS Keychain (no token in the config file)

Store the token in Keychain, then point the server at it:

{
  "mcpServers": {
    "1password": {
      "command": "npx",
      "args": ["-y", "@takescake/1password-mcp"],
      "env": {
        "OP_KEYCHAIN_SERVICE": "op-service-account-claude-automation",
        "OP_KEYCHAIN_ACCOUNT": "your-macos-username"
      }
    }
  }
}

Token resolution order: CLI (--service-account-token / --token) → OP_SERVICE_ACCOUNT_TOKEN → macOS Keychain. OP_KEYCHAIN_ACCOUNT is optional when the service name alone is unique. Avoid the CLI flags: command-line arguments are visible to other local processes, and the server logs a warning at startup if you use them.

OpenAI Codex (TOML)

Option A — token in config:

[mcp_servers."1password"]
command = "npx"
args = ["-y", "@takescake/1password-mcp"]

[mcp_servers."1password".env]
OP_SERVICE_ACCOUNT_TOKEN = "YOUR_SERVICE_ACCOUNT_TOKEN"

Option B (recommended) — config only names the env var:

[mcp_servers."1password"]
command = "npx"
args = ["-y", "@takescake/1password-mcp"]
env_vars = ["OP_SERVICE_ACCOUNT_TOKEN"]

Set OP_SERVICE_ACCOUNT_TOKEN in your shell or CI. Note: codex mcp add ... --env OP_SERVICE_ACCOUNT_TOKEN=... writes the secret into Codex config; prefer env_vars when you can.

On macOS you can omit the token env and use OP_KEYCHAIN_SERVICE (+ optional OP_KEYCHAIN_ACCOUNT) instead.

Optional: restrict the server to certain vaults

By default the server can use any vault the service account can see. To allow-list vaults:

{
  "env": {
    "OP_SERVICE_ACCOUNT_TOKEN": "YOUR_SERVICE_ACCOUNT_TOKEN",
    "OP_MCP_ALLOWED_VAULTS": "Automation, CI"
  }
}

Names or IDs work (case-insensitive). Same setting via --allowed-vaults. The allow-list applies server-wide, to every tool and resource that touches a vault, not only op_run / op_check_ref:

• vault_list and onepassword://vaults show only allowed vaults.
• Tools that take a vaultId, and the onepassword://vaults/{vaultId}/items resource, must be given the vault’s ID (not its name); vaults outside the list are rejected.
• op:// references are checked both as written and by the vault they actually resolve to.
• When an allow-list is set, each guarded call makes one extra vaults.list read (mind service-account rate limits), and the server fails closed if vaults can’t be listed.

Upgrading from 4.0.3 or earlier? If you set this expecting it to affect only op_run / op_check_ref, it now restricts everything.

This is defense in depth: scope the service account’s own vault access in 1Password first.

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For agents: how to handle secrets

Follow this order every time:

1. Discover with vault_list → item_lookup / item_list (metadata only).
2. Confirm a reference with op_check_ref — never reveal just to see if a path exists.
3. Use a secret in a command or API call with op_run and op://vault/item/field in env.
4. Reveal with password_read / item_get + reveal: true only when the human explicitly needs the value in chat.
5. Rotate with password_generate → password_update (keep returnSecret: false unless asked).
6. Prefer item_archive over item_delete unless permanent removal is required.

op_run sketch

{
  "argv": ["curl", "-sS", "https://api.example.com/health"],
  "env": {
    "API_TOKEN": "op://Automation/Example API/credential"
  },
  "timeout_ms": 60000
}

Prefer argv over a shell command string when you can — fewer quoting surprises.

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Configuration reference

Environment variables

Variable	Required	Description
OP_SERVICE_ACCOUNT_TOKEN	Usually yes	Service account token. Not required on macOS if Keychain vars are set.
OP_KEYCHAIN_SERVICE	No	macOS: Keychain service name for the token.
OP_KEYCHAIN_ACCOUNT	No	macOS: optional account to narrow the Keychain lookup.
OP_MCP_ALLOWED_VAULTS	No	Comma-separated vault names/IDs (case-insensitive) the server may use, enforced server-wide. Empty = unrestricted.
OP_INTEGRATION_NAME	No	Name reported to the 1Password SDK (default: 1password-mcp).
OP_INTEGRATION_VERSION	No	Version reported to the SDK (default: package version).
MCP_LOG_LEVEL	No	debug | info | warn | error (default: info).
MCP_DEBUG	No	If set, forces debug logging.

CLI flags

--service-account-token <token>   1Password service account token (avoid: visible to other local processes)
--token <token>                   Alias for --service-account-token
--log-level <level>               error | warn | info | debug (default: info)
--integration-name <name>         Custom integration name for the 1Password SDK
--integration-version <version>   Custom integration version
--allowed-vaults <list>           Comma-separated vault allow-list (names or IDs), applied server-wide

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Security & privacy

Read this before pointing the server at a vault you care about.

• LLM privacy — Anything revealed to the model may be sent to your AI provider and retained under their policies.
• MCP is not end-to-end encrypted for secrets in flight — Values are plaintext inside the MCP workflow and toward the model. They are encrypted at rest in 1Password once stored.
• Best fit — Automation credentials: CI tokens, bot accounts, disposable env secrets.
• Avoid — Banking, primary personal logins, recovery codes, or anything you cannot afford to expose to a model provider.
• Token = master key — Scope the service account tightly; rotate immediately if leaked; never commit tokens or MCP configs with secrets.
• Prefer the env var or Keychain for the token — --token / --service-account-token puts it in the process arguments, which other local processes can read (the server warns at startup). A same-user process can generally read the server’s environment too (for example /proc/<pid>/environ on Linux), so on macOS Keychain is the strongest option: it keeps the token out of config files and the process environment.
• Prefer references — op://… + op_run beat pasting passwords into prompts or files.
• op_run runs arbitrary commands as your user — Keep your MCP client’s approval prompts on for it; don’t auto-approve it.
• Redaction is best effort — op_run masks resolved secrets in returned output, including common encodings (base64, JSON- and URL-encoded forms, multi-line values). That protects against accidental disclosure. It is not a sandbox: a command can deliberately transform or transmit a secret it was given.
• Notes are not concealed — item_get returns notes as-is (like op item get). Don’t keep secrets in the notes of vaults an agent can read.
• Least privilege — Dedicated automation vaults beat sharing your whole account. OP_MCP_ALLOWED_VAULTS is a second fence, not a substitute.
• Reporting vulnerabilities — Open a public issue; see SECURITY.md.

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Protocol & compatibility

Piece	Detail
Package	@takescake/1password-mcp
Runtime	Node.js ≥ 20
Transport	stdio
MCP SDK	@modelcontextprotocol/server v2
Protocol	Negotiates 2026-07-28; keeps legacy client compatibility
Registry name	io.github.CakeRepository/1password

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Development

git clone https://github.com/CakeRepository/1Password-MCP.git
cd 1Password-MCP
npm ci
npm run build
npm test
npm run lint

Watch mode: npm run dev.

Project layout

src/
  index.ts                 # Entrypoint — MCP stdio + protocol negotiation
  server.ts                # buildServer() — registers tools, prompts, resources
  config.ts                # CLI / env / Keychain / allow-list
  client.ts                # 1Password SDK client
  logger.ts                # Structured logs on stderr (stdout is protocol)
  secret-ref.ts            # op:// parsing & reference checks
  vault-access.ts          # Server-wide vault allow-list enforcement
  redaction.ts             # op_run output redaction
  utils.ts                 # Result helpers, password generation
  tools/                   # All 15 MCP tools
  prompts/                 # Interactive workflow prompts
  resources/               # onepassword:// resources
tests/

See CONTRIBUTING.md. Maintainers / agents: agents.md.

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Changelog

See CHANGELOG.md for version history, including the 5.0.0 release (resource URIs moved from 1password:// to onepassword://, plus security hardening; read its Changed notes before upgrading), the 4.0.0 MCP v2 / 2026-07-28 migration, and the 3.0.0 op_run / reveal-opt-in security changes.

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License

Apache License 2.0