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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=false, so the agent knows it mutates local state but is not destructive. The description adds nothing beyond that: it does not say whether accepting consumes the swap code, whether a decline is reversible, or who is permitted to answer a given offer.

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?

A single well-formed sentence with the verb first and the required input mentioned last; there is no filler or redundancy.

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 two-parameter state-changing tool with no output schema, the definition covers the happy path but omits outcomes: what a successful accept returns, what error looks like for a bad or stale code, and whether a declined offer can be answered again later.

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 50% – the 'code' parameter is documented while the 'accept' boolean is not. The description's 'Accept or turn down' does map onto accept=true/false, adding a small amount of meaning the bare boolean lacks, which is the right baseline for partial coverage.

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 a specific action pair ('Accept or turn down') on a specific resource ('a swap someone offered you'), which cleanly separates it from the offer-side sibling offer_trade. It stops short of naming that sibling explicitly, so the contrast must be inferred.

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?

'someone offered you' implies the precondition that a swap must already exist, but there is no explicit statement of when to use this versus offer_trade, nor what to do if the offer expired or the code is invalid.

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