retrieveInstancesListList instances - List and filter all instances in your account
| Name | Required | Description | Default |
|---|---|---|---|
| name | No | ||
| page | No | ||
| size | No | ||
| region | No | ||
| search | No | ||
| status | No | ||
| orderBy | No | ||
| addOnIds | No | ||
| ipConfig | No | ||
| tenantId | No | ||
| customerId | No | ||
| dataCenter | No | ||
| instanceId | No | ||
| productIds | No | ||
| x-trace-id | No | ||
| displayName | No | ||
| instanceIds | No | ||
| productTypes | No | ||
| x-request-id | Yes |
Changes observed during successful MCP inspections.
Input schema / properties / x-hapi-auth-stateRemoved value: -{
- "type": "string"
-}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds no additional behavioral context beyond restating the tool's functionality; no disclosure of pagination behavior, response format, or other side effects.
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?
The description is redundant, saying 'List instances' and then 'List and filter all instances' – two phrasings of the same idea. This wastes words without adding substance.
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?
Given 19 parameters, no output schema, and a complex list/filter operation, the description is severely incomplete. It fails to mention return format, pagination, filter specifics, or the required x-request-id header, making it inadequate for correct invocation.
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?
Schema description coverage is 0% across 19 parameters, and the description does not explain any parameter meanings. It only generically says 'list and filter' without detailing how filters work or which parameters control behavior.
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?
The description clearly states the verb (List) and resource (instances) with scope ('in your account'). It distinguishes from retrieveInstance (singular) by being plural, but does not explicitly differentiate from other sibling list tools.
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?
No guidance on when to use this tool versus alternatives like retrieveInstance. It only scopes to account instances, providing no exclusions or alternative recommendations.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.