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

Annotations already declare readOnly, idempotent, open-world and non-destructive, so the safety profile is covered structurally. The description adds value beyond them by disclosing pagination behavior ('cursor-paginated'), the top-level return key ('full user objects under `users`'), and the scope boundary (accounts, not posts). It omits rate limits or auth requirements, hence not a 5.

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?

Front-loaded with the core action, then the selection heuristic, then the pagination/return note, then the sibling disambiguation — every sentence earns its place. The trailing pricing block is boilerplate metadata rather than description prose and does not dilute the useful content.

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 read-only, open-world search with an output schema and full annotation coverage, the description supplies everything needed to call it correctly: what it searches, when to prefer it, how it pages, where results land, and which sibling to use instead for tweet content. Nothing material 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 description coverage is 100%, so the schema already documents both 'query' and 'cursor'; the baseline is 3. The description reinforces the keyword-based search and pagination framing but adds no syntax or format detail beyond the schema, and does not address why 'query' is optional despite being the core input.

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+resource ('Search X user accounts by keyword') and the return shape ('matching profiles'). It explicitly distinguishes itself from the nearest functional sibling, get_twitter_tweet_advanced_search, and implicitly from the exact-handle lookup tools, so an agent can pick it without opening another 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 concrete selection condition ('when you know roughly who you are looking for — a company name, a topic, a partial handle — but not the exact @handle') and names the alternative for the adjacent case ('to search tweet content use get_twitter_tweet_advanced_search'). Both the when and the routing alternative are explicit.

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