List bookmarks

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds the context that bookmarks are scoped to the current user and explains what a bookmark is ('a named position in seconds'). However, it does not disclose any additional behavioral traits such as pagination, ordering, or rate limits, which would be useful for a list tool. The description does not contradict the 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 two sentences long, front-loaded with the main purpose, and contains no redundant words. Every sentence serves a purpose: stating the scope and defining a bookmark.

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 (2 parameters, no output schema, no nested objects), the description is largely complete. It explains the resource, optional filtering, and the definition of a bookmark. It could be more complete by mentioning the return format (though the 'detail' parameter description partially covers that) or pagination, but for a straightforward list tool, it is sufficient.

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 coverage is 100%, so the input schema already describes both parameters with clear descriptions. The description's mention of 'either all of them, or those of one library item' merely paraphrases the library_item_id parameter, adding no new semantic value. The baseline of 3 is appropriate since the schema does the heavy lifting.

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 uses a specific verb ('list') and resource ('bookmarks of the current user'), clearly distinguishing it from sibling tools like create_bookmark or update_bookmark. It also specifies the optional filtering by library item, leaving no ambiguity about what the tool does.

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 explicitly states when to use the filter parameter (to restrict to a specific library item) and implies the default behavior (all bookmarks). It does not explicitly mention alternatives or when not to use the tool, but given the sibling set lacks another list-bookmarks tool, the guidance is clear enough. A small deduction for not stating the use case for the 'detail' parameter.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.