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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=true), so the description's job is additive context, and it delivers: the response includes max_follows so 'N of 50' can be reported without a second call, includes list associations and nicknames, and is scoped strictly to the API key's owner. It does not discuss ordering or whether follows are paginated, which is the 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?

Three sentences, front-loaded with the return payload before the access-scope caveat. The 'N of 50' example earns its place by telling the agent why max_follows matters rather than just listing it.

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 and there are no parameters, so the description only needs to cover scope and the notable return fields — both are done, including the unusual max_follows field and the per-row associations. Nothing an agent needs to call this 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?

Zero parameters, so there is nothing to mis-specify and the baseline is 4. The description correctly describes max_follows as a returned field rather than an input, avoiding the confusion of implying a filter exists.

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 — every wallet the CALLER follows — plus the extra payload each row carries (max_follows, list associations, nicknames). The clause 'This returns the CURRENT USER's own data, resolved from their API key' cleanly separates it from get_whale_wallet_* and search_whalewatch_wallets, which query other people's wallets.

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?

The description makes clear when this tool applies (you want your own follow list) and rules out querying someone else's follows. However, it never names the adjacent alternatives an agent would realistically weigh — get_my_following_feed for activity from followed wallets, get_my_wallets for wallet holdings, or follow_wallet/unfollow_wallet for mutation — so routing is left to inference from names.

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