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

Annotations already declare read-only, idempotent, non-destructive and closed-world behavior, so the safety profile is covered. The description adds genuinely useful behavioral context beyond that: matching is lexical rather than semantic, and empty results should prompt reformulation rather than telling the agent the data is absent.

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?

Three tight sentences, each doing distinct work: what is searched, how matching behaves, and how to narrow to a single media item. The scope constraint is front-loaded and there is no filler.

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?

With an output schema present, return values need not be explained. For a zero-required-parameter, two-param search tool, the description supplies everything an agent needs: search domain, matching semantics, and the media_id routing path.

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 baseline is 3, but the description adds meaning the schema does not: query searches only the note body (not the media title/author), and media_id is the id of the underlying book/article/podcast. It also clarifies the query-optional interaction with media_id, which aids correct invocation.

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 ('Search the user's literature notes') and immediately bounds the search scope to note text rather than title or author. That scoping detail distinguishes it from siblings like search_notes, search_media and search_drafts without requiring the agent to open any schema.

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 concrete guidance: keyword search is literal, so retry with different wording if nothing is found, and pass media_id to retrieve all notes on one book/article/podcast. It does not explicitly name sibling alternatives (e.g. use search_notes for non-literature notes), so it stops just short of full when/when-not routing.

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