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 genuinely useful behavioral trait beyond them: matching is literal keyword matching, not semantic, which predicts false negatives and shapes retry behavior.

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, zero filler, and the positive scope is front-loaded before the matching caveat and the exclusion list. Every clause carries load.

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 one-parameter read-only search, the description covers scope, matching behavior, failure recovery and exclusions; return values are covered by the output schema and safety by annotations. Nothing an agent needs to call it correctly is missing.

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% for the single required parameter, so the schema already documents 'query' as a keyword or tag. The description's 'by keyword or tag' restates that without adding syntax, matching rules, or examples, so 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?

Specific verb (search) plus a precisely scoped resource (the user's own insights / notes written in their own words), and it explicitly carves out what it is not for (books, articles, podcasts, and notes on them). That exclusion set lets an agent distinguish it from search_literature_notes and search_media without opening either 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 a clear usage context and a concrete recovery heuristic ('try another wording if nothing is found'), plus an explicit when-not list. It stops short of naming the alternative sibling tools (search_literature_notes, search_media) by name, so routing relies on the agent mapping content types to those siblings itself.

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