List the 1Password vaults accessible to a service account, returning vault IDs, names, descriptions, and types. Use it to identify which vaults an integration can access.
List the 1Password vaults accessible to the service account (limited to the allow-listed vaults when OP_MCP_ALLOWED_VAULTS / --allowed-vaults is configured). Returns vault IDs, names, descriptions, and types.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v4.0.1Input schema / $schemaPrevious value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"v2.4.2Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden and does disclose a real behavioral constraint: results shrink to the allow-listed vaults when OP_MCP_ALLOWED_VAULTS / --allowed-vaults is configured. It also specifies returned fields. It stops short of stating read-only nature, auth requirements, or pagination/rate limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two compact sentences, front-loaded with the core action and followed by the scoping caveat and return fields. No filler or repetition.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a parameterless read tool this is nearly complete: scope, filtering behavior, and return shape are all covered, which compensates for the absent output schema. Only auth/permission expectations and result-size behavior are unstated.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The mention of returned fields is return-value information rather than parameter semantics.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource ("List the 1Password vaults") and scopes it precisely to those accessible to the service account. An agent can immediately distinguish this vault-enumeration tool from the many item_* siblings that operate on items within vaults.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The allow-list caveat implies the tool is the discovery entry point, but there is no explicit when-to-use guidance, no mention of prerequisites (e.g., required credentials), and no routing to alternatives such as item_list for enumerating contents. Usage must be inferred.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.