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

Annotations already declare readOnlyHint=true and destructiveHint=false; the description adds value beyond them by disclosing the return granularity (names and ids only), the identity resolution mechanism (resolved from the API key), and the hard boundary that no other user's wallet can be queried. The statement that adding/removing tokens is unavailable is consistent with, not a repeat of, the read-only hint.

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 fact and the hand-off, and every sentence is short. The final two sentences ("resolved from their API key" and "no way to ask about someone else's wallet") restate the same user-scoping guarantee, which is mild redundancy rather than wasted space.

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, so return fields needn't be enumerated; the description still usefully signals the result is names and ids only. For a single-param, read-only list tool, an agent has everything needed: what it returns, what it cannot do, which tool continues the workflow, and whose data it is.

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?

There is one parameter with 0% schema description coverage, so the description must carry the load. It only says "on one network" without naming solana, while the schema pins network via const with a default — making the parameter effectively choice-free. The gap is small given the const, but the description adds no format or constraint detail beyond what the schema already enforces.

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?

The opening sentence gives a specific verb scope and resource ("The user's watchlists on one network — names and ids only"), plus the return shape. It actively disambiguates from siblings by naming get_my_watchlist_tokens and get_my_balances, and clarifies that a watchlist is followed tokens, not holdings — a distinction that matters among ~70 siblings.

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?

Explicit entry-point guidance ("Start here for 'what's on my watchlist'...") plus an explicit hand-off path ("Pass an id to get_my_watchlist_tokens to read a list's contents"). It also states what the tool cannot do (add/remove tokens, query other wallets) and which sibling covers balances instead.

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