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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds genuine context beyond that: the numbers are computed at your notional and are net of fees, and it signals the return is an analytical breakdown (win rate, capacity, reasons). It says nothing about behavior for an unknown or stale market_id, which is the remaining risk.

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?

One sentence, front-loaded with the resource and followed by the returned metrics; the parenthetical id provenance sits in a sensible spot. No filler.

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?

There is no output schema, so the description must carry the return contract, and it does by listing the six analytical outputs. What's missing is how side affects the result and what happens if the market_id is unknown — modest gaps for a read-only lookup.

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 only 33% – notional is the sole documented property. The description compensates for the required market_id by tying it to fixed_vs_floating, and "at your size net of fees" implies notional drives the output. The side parameter (short/long) is explained by neither the schema nor the description beyond its enum values, leaving a real gap.

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 (one Boros market) and enumerates what comes back: fixed rate at size net of fees, floating benchmarks, advantage, win rate, capacity, reasons. It also distinguishes itself from the sibling fixed_vs_floating by naming that tool as the source of the id. It is phrased as a noun phrase rather than a verb, but the intent is unambiguous.

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?

"id from fixed_vs_floating" gives clear provenance and therefore the workflow context: call this after screening markets in the sibling tool. It doesn't state exclusions (e.g., when to prefer best_opportunities or pair_breakdown), so it falls short of a full when/when-not treatment.

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