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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description still earns credit by disclosing a non-obvious behavioral trait: fuzzy matching ('forgives small typos') and the fact that coverage spans all lists plus the Inbox. It does not mention result ordering, limits, or ranking, which for a search tool is a modest remaining gap.

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?

Scope is front-loaded in the first clause, matching behavior follows, and the two use cases close it out. Every clause carries information; nothing is padding.

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?

Two parameters, one required, full schema descriptions, and no output schema to explain. The description covers scope, matching behavior, and invocation intent, which is everything an agent needs to call this correctly.

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 baseline would be 3. The description adds genuine meaning beyond the schema by expanding the matchable fields for query to include list title and link site, which the schema's own wording omits. It says nothing extra about the optional list parameter beyond the schema's 'slug or title' note, keeping it from a 5.

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 with explicit scope: the person's own picks across every list they made, Inbox included, matched on name, note, details, list title or link site. An agent immediately knows what domain this searches. It does not, however, distinguish itself from siblings like search_library or search_lists, which sound adjacent.

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 two concrete use cases: retrieving something the person kept, and duplicate-checking before add_item, the latter explicitly naming a sibling. That is real routing guidance. It stops short of stating when to prefer search_library or search_lists instead, so the sibling boundary is left implicit.

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