Bookmark statistics

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

With no annotations, the description carries the full transparency burden. It discloses specific computed stats, including the nuanced age-distribution phrasing ('sat untouched for years'), giving the agent insight into the output. It does not explicitly state read-only behavior, but the nature of a stats tool makes that implied.

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 sentences with no fluff. The first sentence lists what the tool returns, the second gives usage advice. Every word earns its place, and the informal tone ('pile') is concise and memorable.

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 stats tool with one optional parameter, the description covers the returned metrics and when to use it. It does not detail the exact return format (no output schema), but the listed metrics are sufficient for an agent to understand the tool's results. A minor gap is the lack of explicit read-only confirmation.

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 provides a thorough description of the 'source' parameter, including examples and semantics. The tool description adds no additional parameter 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 clearly states the tool provides a statistical overview: total count, per-source counts, age distribution, and top domains. This specifically distinguishes it from siblings like list_bookmarks (listing) and search_bookmarks (filtering), making the purpose unambiguous.

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?

'A good first call before triaging' gives a clear situational context for when to use this tool, implying it should precede more detailed exploration. It does not explicitly list alternatives or exclusions, but the guidance is sufficient for most agents.

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