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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds value by enumerating what the payload contains (price, lent, borrowed, free to short, lender APR, shorter APR, USDG borrowing rate, BORRO Drip dollars/day and deposit rate), but phrases it vaguely ('one number each') and says nothing about ordering, completeness, or how the Drip estimate is computed.

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?

It is a single sentence with no filler pleasantries, and every clause carries content. But it is a long run-on with nested parentheticals ('one number each, $BORRO included once it has been paid'), which makes it harder to parse than a short front-loaded summary followed by bullets would be.

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 needs to carry return-value semantics, and it does enumerate the main fields. It is still incomplete for a market-overview tool: no mention of scope (all stocks vs. filtered), sort order, units/decimals, or what 'free to short' and the Drip estimate actually mean operationally.

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. Baseline for a parameterless tool is 4.

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 does convey the resource: an overview of every stock market on Borro plus the USDG vault, with lending/borrowing metrics. However, it never uses a clear verb (list/aggregate/get) and does nothing to distinguish itself from close siblings like 'market', 'prices', 'credit_markets', or 'farms', leaving an agent to guess whether this is a list of one market or an aggregate of all.

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?

There is no statement of when to use this tool versus 'market' (singular), 'prices', or 'credit_markets'. Usage is only implied by the enumeration of included data, so the agent must infer routing from names alone.

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