list_sub_accountsDiscover all sub-accounts under a parent Canvas account ID to navigate and manage account structures effectively.
List sub-accounts under a given Canvas account.
| Name | Required | Description | Default |
|---|---|---|---|
| account_id | Yes | The parent Canvas account ID |
Changes observed during successful MCP inspections.
v1.18.11Input schema / $schemaPrevious value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"v1.18.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description's 'List' is consistent with the provided readOnlyHint=true annotation, and it adds no additional behavioral context beyond what annotations already declare. It does not mention pagination, response shape, or any edge-case behavior, but since annotations cover the read-only nature, the description meets the minimum bar. No contradiction with annotations.
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 a single, short sentence that is front-loaded with the key action (List sub-accounts) and context (under a given Canvas account). Every word earns its place, and there is no extraneous information.
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 simple tool with one parameter, read-only annotations, and no output schema, the description is nearly complete. An agent can understand the purpose and parameter. It could mention pagination or the hierarchical scope of sub-accounts, but these are minor gaps given the tool's simplicity and the existing schema/annotations.
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 input schema already documents account_id as 'The parent Canvas account ID' with 100% coverage. The description's 'under a given Canvas account' merely echoes the schema and does not add new semantic detail, so the baseline score of 3 applies.
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 states a specific verb and resource, 'List sub-accounts under a given Canvas account,' which clearly conveys what the tool does. While it does not explicitly contrast with sibling tools like list_accounts or get_account, the 'sub-accounts' wording inherently distinguishes it from account-listing 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?
The phrase 'under a given Canvas account' implies the tool is used when you need sub-accounts for a specific parent account, with account_id as the required context. However, there is no explicit guidance about when to choose this tool over alternatives such as list_accounts or get_account, leaving the selection largely to inference.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.