Shows all available lists with their item counts so you can locate a list ID or verify how many lists exist in the current session.
Lists all existing lists and their item counts.
WHEN TO USE:
To see all available lists in the current session
To find a list ID you may have forgotten
To check how many lists exist
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations provided, so the description carries full burden. It correctly implies a read-only operation and lists output includes item counts, but lacks details on performance, data freshness, or any 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 concise and well-structured with a clear main sentence followed by a 'WHEN TO USE' list. Every sentence serves a purpose with no wasted words.
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 the tool's simplicity (no parameters, no output schema), the description is reasonably complete: it states the action and output (list IDs and item counts) and provides usage guidance. Minor missing information about output format or limits.
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?
Input schema has zero parameters, so schema coverage is 100%. The description does not need to add parameter meaning. Baseline score of 4 is appropriate.
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 'Lists all existing lists and their item counts', using a specific verb and resource. It distinguishes from sibling tools like get_list (single list) and create_list (creation).
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 description includes a 'WHEN TO USE' section with three clear use cases. It does not explicitly mention when not to use or alternatives, but the guidance is sufficient for this simple tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.