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

Goes well beyond the annotations by describing the return payload ({to, data, value, chainId} on Base), the fact that nothing happens until the caller signs and broadcasts, and the custody model ('Liquid never holds keys or funds'). This is exactly the kind of pre-signing workflow context an agent needs.

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 and information-dense: cost, action, asset scope, return shape, signing requirement, follow-up tool. The one-word 'Free.' opener is slightly clipped but still earns its place as an early decision signal.

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 zero-parameter preparation tool with an output schema and full annotation coverage, the description supplies the missing workflow context (unsigned tx, self-custody, follow-up lookup). Everything needed to call it correctly is present.

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?

The tool takes zero parameters, so there is nothing for the description to clarify; the baseline of 4 applies. No misleading parameter claims are made.

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 (opens) plus resource (your own vault for the tokenized US stock basket), and it even names the covered assets. An agent can distinguish this creation tool from stocks_vault (a lookup) and stocks_basket without opening a 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?

States the cost context ('Free') and gives explicit follow-up routing: 'After it confirms, find the vault with stocks_portfolio.' It does not, however, state when NOT to call it or contrast it with the similarly named sibling stocks_vault.

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