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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds a meaningful behavioral trait: results are truncated at 50 and the call therefore cannot serve as a count, which is a caveat beyond 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?

Two short sentences with no filler; the purpose is front-loaded and the disqualifying condition follows immediately. Every clause earns its place.

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?

An output schema exists, so return values need not be described, and annotations carry the safety profile. Purpose, scope, and the counting exclusion are all present; ordering semantics for 'recent' are the only minor omission, and the tool name and title make that self-evident.

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?

Single parameter with 100% schema description coverage; the schema already documents limit, its default of 10 and its max of 50. The description adds no syntax or interpretation beyond what the schema provides, so the baseline 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?

States a specific verb and resource ('List the user's most recently created insights (notes)') and disambiguates from the count_* family with the explicit 'Not for counting' clause. It does not explicitly contrast with search_notes, but the counted-vs-listed distinction against siblings is clear.

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?

Gives an explicit when-not ('Not for counting') with the rationale (50-note cap means it cannot report totals), which routes the agent away from count_notes. It lacks an explicit pointer to the alternative for filtered retrieval (search_notes) or for other note types.

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