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

Annotations declare readOnlyHint=true and openWorldHint=false, and the description reinforces this by stating the user reviews on The River, signs in their own wallet, and 'nothing happens until they do' — valuable non-execution context beyond the annotations. It also adds validation constraints (usd buy-only, 6 vs 18 decimals) that the annotations do not cover.

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 what the tool produces, then the parameter rule, then the user-consent behavior. Dense but each sentence carries information; only the opening fragment 'A pre-filled River trade link.' is slightly terse.

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 no output schema, the description adequately conveys the return (a best-price link opening the cheapest issuer). It explains buy semantics well but leaves sell-mode behavior (e.g., whether usd is allowed on sell) unstated for a tool whose side enum includes 'sell'.

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 83% and the schema only says 'Plain decimal' for usd/qty, but the description adds real meaning: usd is buy-only settlement-stablecoin with max 6 decimals, qty is tokens with max 18 decimals, and exactly one must be supplied. That mutual-exclusion rule appears nowhere in the schema.

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 description names the specific resource (a pre-filled River trade link) and the operation that produces it, so an agent knows this tool generates a shareable order link rather than executing a trade. It stops short of distinguishing itself from strategy_link, the other link-generating sibling, leaving that comparison to inference.

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?

It gives concrete selection rules: exactly one of usd or qty, and 'a buy by ticker with usd (no address or chain)' as the path that yields a best-price link. It does not explicitly say when to prefer this over strategy_link or list_stocks, so it is clear context without exclusions.

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